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Transcriber's notes:
Underscores before and after words denote italics.
Underscore and {} denote subscripts.
Footnotes moved to end of book.
The book starts using the word "CHAPTER" only after its chapter
number XI. I have left it the same in this text.
The Century Books of Useful Science
CREATIVE CHEMISTRY
Descriptive of Recent Achievements in the Chemical Industries
by
EDWIN E. SLOSSON, M.S., PH.D.
Literary Editor of _The Independent_, Associate in Columbia School of
Journalism
Author of "Great American Universities," "Major Prophets of Today," "Six
Major Prophets," "On Acylhalogenamine Derivatives and the Beckmann
Rearrangement," "Composition of Wyoming Petroleum," etc.
With Many Illustrations
[Illustration (Decorative)]
New York
The Century Co.
Copyright, 1919, by
The Century Co.
Copyright, 1917, 1918, 1919, by
The Independent Corporation
Published, October, 1919
[Illustration: From "America's Munitions"
THE PRODUCTION OF NEW AND STRONGER FORMS OF STEEL IS ONE OF THE GREATEST
TRIUMPHS OF MODERN CHEMISTRY
The photograph shows the manufacture of a 12-inch gun at the plant of
the Midvale Steel Company during the late war. The gun tube, 41 feet
long, has just been drawn from the furnace where it was tempered at
white heat and is now ready for quenching.]
TO MY FIRST TEACHER
PROFESSOR E.H.S. BAILEY OF THE UNIVERSITY OF KANSAS
AND MY LAST TEACHER
PROFESSOR JULIUS STIEGLITZ OF THE UNIVERSITY OF CHICAGO
THIS VOLUME IS GRATEFULLY DEDICATED
CONTENTS
I THREE PERIODS OF PROGRESS 3
II NITROGEN 14
III FEEDING THE SOIL 37
IV COAL-TAR COLORS 60
V SYNTHETIC PERFUMES AND FLAVORS 93
VI CELLULOSE 110
VII SYNTHETIC PLASTICS 128
VIII THE RACE FOR RUBBER 145
IX THE RIVAL SUGARS 164
X WHAT COMES FROM CORN 181
XI SOLIDIFIED SUNSHINE 196
XII FIGHTING WITH FUMES 218
XIII PRODUCTS OF THE ELECTRIC FURNACE 236
XIV METALS, OLD AND NEW 263
READING REFERENCES 297
INDEX 309
A CARD OF THANKS
This book originated in a series of articles prepared for _The
Independent_ in 1917-18 for the purpose of interesting the general
reader in the recent achievements of industrial chemistry and providing
supplementary reading for students of chemistry in colleges and high
schools. I am indebted to Hamilton Holt, editor of _The Independent_,
and to Karl V.S. Howland, its publisher, for stimulus and opportunity to
undertake the writing of these pages and for the privilege of reprinting
them in this form.
In gathering the material for this volume I have received the kindly aid
of so many companies and individuals that it is impossible to thank them
all but I must at least mention as those to whom I am especially
grateful for information, advice and criticism: Thomas H. Norton of the
Department of Commerce; Dr. Bernhard C. Hesse; H.S. Bailey of the
Department of Agriculture; Professor Julius Stieglitz of the University
of Chicago; L.E. Edgar of the Du Pont de Nemours Company; Milton Whitney
of the U.S. Bureau of Soils; Dr. H.N. McCoy; K.F. Kellerman of the
Bureau of Plant Industry.
E.E.S.
LIST OF ILLUSTRATIONS
The production of new and stronger forms of steel is one
of the greatest triumphs of modern chemistry _Frontispiece_
FACING PAGE
The hand grenades contain potential chemical energy
capable of causing a vast amount of destruction
when released 16
Women in a munition plant engaged in the manufacture
of tri-nitro-toluol 17
A chemical reaction on a large scale 32
Burning air in a Birkeland-Eyde furnace at the DuPont
plant 33
A battery of Birkeland-Eyde furnaces for the fixation of
nitrogen at the DuPont plant 33
Fixing nitrogen by calcium carbide 40
A barrow full of potash salts extracted from six tons of
green kelp by the government chemists 41
Nature's silent method of nitrogen fixation 41
In order to secure a new supply of potash salts the United
States Government set up an experimental plant at
Sutherland, California, for utilization of kelp 52
Overhead suction at the San Diego wharf pumping kelp
from the barge to the digestion tanks 53
The kelp harvester gathering the seaweed from the Pacific
Ocean 53
A battery of Koppers by-product coke-ovens at the plant
of the Bethlehem Steel Company, Sparrows Point,
Maryland 60
In these mixing vats at the Buffalo Works, aniline dyes
are prepared 61
A paper mill in action 120
Cellulose from wood pulp is now made into a large variety
of useful articles of which a few examples are here
pictured 121
Plantation rubber 160
Forest rubber 160
In making garden hose the rubber is formed into a tube
by the machine on the right and coiled on the table
to the left 161
The rival sugars 176
Interior of a sugar mill showing the machinery for crushing
cane to extract the juice 177
Vacuum pans of the American Sugar Refinery Company 177
Cotton seed oil as it is squeezed from the seed
by the presses 200
Cotton seed oil as it comes from the compressors flowing
out of the faucets 201
Splitting coconuts on the island of Tahiti 216
The electric current passing through salt water in these
cells decomposes the salt into caustic soda and
chlorine gas 217
Germans starting a gas attack on the Russian lines 224
Filling the cannisters of gas masks with charcoal made
from fruit pits--Long Island City 225
The chlorpicrin plant at the Bdgewood Arsenal 234
Repairing the broken stern post of the _U.S.S. Northern
Pacific_, the biggest marine weld in the world 235
Making aloxite in the electric furnaces by fusing coke
and bauxite 240
A block of carborundum crystals 241
Making carborundum in the electric furnace 241
Types of gas mask used by America, the Allies and Germany
during the war 256
Pumping melted white phosphorus into hand grenades
filled with water--Edgewood Arsenal 257
Filling shell with "mustard gas" 257
Photomicrographs showing the structure of steel made by
Professor E.G. Mahin of Purdue University 272
The microscopic structure of metals 273
INTRODUCTION
BY JULIUS STIEGLITZ
Formerly President of the American Chemical Society, Professor of
Chemistry in The University of Chicago
The recent war as never before in the history of the world brought to
the nations of the earth a realization of the vital place which the
science of chemistry holds in the development of the resources of a
nation. Some of the most picturesque features of this awakening reached
the great public through the press. Thus, the adventurous trips of the
_Deutschland_ with its cargoes of concentrated aniline dyes, valued at
millions of dollars, emphasized as no other incident our former
dependence upon Germany for these products of her chemical industries.
The public read, too, that her chemists saved Germany from an early
disastrous defeat, both in the field of military operations and in the
matter of economic supplies: unquestionably, without the tremendous
expansion of her plants for the production of nitrates and ammonia from
the air by the processes of Haber, Ostwald and others of her great
chemists, the war would have ended in 1915, or early in 1916, from
exhaustion of Germany's supplies of nitrate explosives, if not indeed
from exhaustion of her food supplies as a consequence of the lack of
nitrate and ammonia fertilizer for her fields. Inventions of substitutes
for cotton, copper, rubber, wool and many other basic needs have been
reported.
These feats of chemistry, performed under the stress of dire necessity,
have, no doubt, excited the wonder and interest of our public. It is far
more important at this time, however, when both for war and for peace
needs, the resources of our country are strained to the utmost, that the
public should awaken to a clear realization of what this science of
chemistry really means for mankind, to the realization that its wizardry
permeates the whole life of the nation as a vitalizing, protective and
constructive agent very much in the same way as our blood, coursing
through our veins and arteries, carries the constructive, defensive and
life-bringing materials to every organ in the body.
If the layman will but understand that chemistry is the fundamental
_science of the transformation of matter_, he will readily accept the
validity of this sweeping assertion: he will realize, for instance, why
exactly the same fundamental laws of the science apply to, and make
possible scientific control of, such widely divergent national
industries as agriculture and steel manufacturing. It governs the
transformation of the salts, minerals and humus of our fields and the
components of the air into corn, wheat, cotton and the innumerable other
products of the soil; it governs no less the transformation of crude
ores into steel and alloys, which, with the cunning born of chemical
knowledge, may be given practically any conceivable quality of hardness,
elasticity, toughness or strength. And exactly the same thing may be
said of the hundreds of national activities that lie between the two
extremes of agriculture and steel manufacture!
Moreover, the domain of the science of the transformation of matter
includes even life itself as its loftiest phase: from our birth to our
return to dust the laws of chemistry are the controlling laws of life,
health, disease and death, and the ever clearer recognition of this
relation is the strongest force that is raising medicine from the
uncertain realm of an art to the safer sphere of an exact science. To
many scientific minds it has even become evident that those most
wonderful facts of life, heredity and character, must find their final
explanation in the chemical composition of the components of life
producing, germinal protoplasm: mere form and shape are no longer
supreme but are relegated to their proper place as the housing only of
the living matter which functions chemically.
It must be quite obvious now why thoughtful men are insisting that the
public should be awakened to a broad realization of the significance of
the science of chemistry for its national life.
It is a difficult science in its details, because it has found that it
can best interpret the visible phenomena of the material world on the
basis of the conception of invisible minute material atoms and
molecules, each a world in itself, whose properties may be nevertheless
accurately deduced by a rigorous logic controlling the highest type of
scientific imagination. But a layman is interested in the wonders of
great bridges and of monumental buildings without feeling the need of
inquiring into the painfully minute and extended calculations of the
engineer and architect of the strains and stresses to which every pin
and every bar of the great bridge and every bit of stone, every foot of
arch in a monumental edifice, will be exposed. So the public may
understand and appreciate with the keenest interest the results of
chemical effort without the need of instruction in the intricacies of
our logic, of our dealings with our minute, invisible particles.
The whole nation's welfare demands, indeed, that our public be
enlightened in the matter of the relation of chemistry to our national
life. Thus, if our commerce and our industries are to survive the
terrific competition that must follow the reëstablishment of peace, our
public must insist that its representatives in Congress preserve that
independence in chemical manufacturing which the war has forced upon us
in the matter of dyes, of numberless invaluable remedies to cure and
relieve suffering; in the matter, too, of hundreds of chemicals, which
our industries need for their successful existence.
Unless we are independent in these fields, how easily might an
unscrupulous competing nation do us untold harm by the mere device, for
instance, of delaying supplies, or by sending inferior materials to this
country or by underselling our chemical manufacturers and, after the
destruction of our chemical independence, handicapping our industries as
they were in the first year or two of the great war! This is not a mere
possibility created by the imagination, for our economic history
contains instance after instance of the purposeful undermining and
destruction of our industries in finer chemicals, dyes and drugs by
foreign interests bent on preserving their monopoly. If one recalls that
through control, for instance, of dyes by a competing nation, control is
in fact also established over products, valued in the hundreds of
millions of dollars, in which dyes enter as an essential factor, one
may realize indeed the tremendous industrial and commercial power which
is controlled by the single lever--chemical dyes. Of even more vital
moment is chemistry in the domain of health: the pitiful calls of our
hospitals for local anesthetics to alleviate suffering on the operating
table, the frantic appeals for the hypnotic that soothes the epileptic
and staves off his seizure, the almost furious demands for remedy after
remedy, that came in the early years of the war, are still ringing in
the hearts of many of us. No wonder that our small army of chemists is
grimly determined not to give up the independence in chemistry which war
has achieved for us! Only a widely enlightened public, however, can
insure the permanence of what farseeing men have started to accomplish
in developing the power of chemistry through research in every domain
which chemistry touches.
The general public should realize that in the support of great chemical
research laboratories of universities and technical schools it will be
sustaining important centers from which the science which improves
products, abolishes waste, establishes new industries and preserves
life, may reach out helpfully into all the activities of our great
nation, that are dependent on the transformation of matter.
The public is to be congratulated upon the fact that the writer of the
present volume is better qualified than any other man in the country to
bring home to his readers some of the great results of modern chemical
activity as well as some of the big problems which must continue to
engage the attention of our chemists. Dr. Slosson has indeed the unique
quality of combining an exact and intimate knowledge of chemistry with
the exquisite clarity and pointedness of expression of a born writer.
We have here an exposition by a master mind, an exposition shorn of the
terrifying and obscuring technicalities of the lecture room, that will
be as absorbing reading as any thrilling romance. For the story of
scientific achievement is the greatest epic the world has ever known,
and like the great national epics of bygone ages, should quicken the
life of the nation by a realization of its powers and a picture of its
possibilities.
CREATIVE CHEMISTRY
La Chimie posséde cette faculté créatrice à un degré plus
éminent que les autres sciences, parce qu'elle pénètre plus
profondément et atteint jusqu'aux éléments naturels des êtres.
--_Berthelot_.
I
THREE PERIODS OF PROGRESS
The story of Robinson Crusoe is an allegory of human history. Man is a
castaway upon a desert planet, isolated from other inhabited worlds--if
there be any such--by millions of miles of untraversable space. He is
absolutely dependent upon his own exertions, for this world of his, as
Wells says, has no imports except meteorites and no exports of any kind.
Man has no wrecked ship from a former civilization to draw upon for
tools and weapons, but must utilize as best he may such raw materials as
he can find. In this conquest of nature by man there are three stages
distinguishable:
1. The Appropriative Period
2. The Adaptive Period
3. The Creative Period
These eras overlap, and the human race, or rather its vanguard,
civilized man, may be passing into the third stage in one field of human
endeavor while still lingering in the second or first in some other
respect. But in any particular line this sequence is followed. The
primitive man picks up whatever he can find available for his use. His
successor in the next stage of culture shapes and develops this crude
instrument until it becomes more suitable for his purpose. But in the
course of time man often finds that he can make something new which is
better than anything in nature or naturally produced. The savage
discovers. The barbarian improves. The civilized man invents. The first
finds. The second fashions. The third fabricates.
The primitive man was a troglodyte. He sought shelter in any cave or
crevice that he could find. Later he dug it out to make it more roomy
and piled up stones at the entrance to keep out the wild beasts. This
artificial barricade, this false façade, was gradually extended and
solidified until finally man could build a cave for himself anywhere in
the open field from stones he quarried out of the hill. But man was not
content with such materials and now puts up a building which may be
composed of steel, brick, terra cotta, glass, concrete and plaster, none
of which materials are to be found in nature.
The untutored savage might cross a stream astride a floating tree trunk.
By and by it occurred to him to sit inside the log instead of on it, so
he hollowed it out with fire or flint. Later, much later, he constructed
an ocean liner.
Cain, or whoever it was first slew his brother man, made use of a stone
or stick. Afterward it was found a better weapon could be made by tying
the stone to the end of the stick, and as murder developed into a fine
art the stick was converted into the bow and this into the catapult and
finally into the cannon, while the stone was developed into the high
explosive projectile. The first music to soothe the savage breast was
the soughing of the wind through the trees. Then strings were stretched
across a crevice for the wind to play upon and there was the Æolian
harp. The second stage was entered when Hermes strung the tortoise shell
and plucked it with his fingers and when Athena, raising the wind from
her own lungs, forced it through a hollow reed. From these beginnings we
have the organ and the orchestra, producing such sounds as nothing in
nature can equal.
The first idol was doubtless a meteorite fallen from heaven or a
fulgurite or concretion picked up from the sand, bearing some slight
resemblance to a human being. Later man made gods in his own image, and
so sculpture and painting grew until now the creations of futuristic art
could be worshiped--if one wanted to--without violation of the second
commandment, for they are not the likeness of anything that is in heaven
above or that is in the earth beneath or that is in the water under the
earth.
In the textile industry the same development is observable. The
primitive man used the skins of animals he had slain to protect his own
skin. In the course of time he--or more probably his wife, for it is to
the women rather than to the men that we owe the early steps in the arts
and sciences--fastened leaves together or pounded out bark to make
garments. Later fibers were plucked from the sheepskin, the cocoon and
the cotton-ball, twisted together and woven into cloth. Nowadays it is
possible to make a complete suit of clothes, from hat to shoes, of any
desirable texture, form and color, and not include any substance to be
found in nature. The first metals available were those found free in
nature such as gold and copper. In a later age it was found possible to
extract iron from its ores and today we have artificial alloys made of
multifarious combinations of rare metals. The medicine man dosed his
patients with decoctions of such roots and herbs as had a bad taste or
queer look. The pharmacist discovered how to extract from these their
medicinal principle such as morphine, quinine and cocaine, and the
creative chemist has discovered how to make innumerable drugs adapted to
specific diseases and individual idiosyncrasies.
In the later or creative stages we enter the domain of chemistry, for it
is the chemist alone who possesses the power of reducing a substance to
its constituent atoms and from them producing substances entirely new.
But the chemist has been slow to realize his unique power and the world
has been still slower to utilize his invaluable services. Until recently
indeed the leaders of chemical science expressly disclaimed what should
have been their proudest boast. The French chemist Lavoisier in 1793
defined chemistry as "the science of analysis." The German chemist
Gerhardt in 1844 said: "I have demonstrated that the chemist works in
opposition to living nature, that he burns, destroys, analyzes, that the
vital force alone operates by synthesis, that it reconstructs the
edifice torn down by the chemical forces."
It is quite true that chemists up to the middle of the last century were
so absorbed in the destructive side of their science that they were
blind to the constructive side of it. In this respect they were less
prescient than their contemned predecessors, the alchemists, who,
foolish and pretentious as they were, aspired at least to the formation
of something new.
It was, I think, the French chemist Berthelot who first clearly
perceived the double aspect of chemistry, for he defined it as "the
science of analysis _and synthesis_," of taking apart and of putting
together. The motto of chemistry, as of all the empirical sciences, is
_savoir c'est pouvoir_, to know in order to do. This is the pragmatic
test of all useful knowledge. Berthelot goes on to say:
Chemistry creates its object. This creative faculty, comparable
to that of art itself, distinguishes it essentially from the
natural and historical sciences.... These sciences do not
control their object. Thus they are too often condemned to an
eternal impotence in the search for truth of which they must
content themselves with possessing some few and often uncertain
fragments. On the contrary, the experimental sciences have the
power to realize their conjectures.... What they dream of that
they can manifest in actuality....
Chemistry possesses this creative faculty to a more eminent
degree than the other sciences because it penetrates more
profoundly and attains even to the natural elements of
existences.
Since Berthelot's time, that is, within the last fifty years, chemistry
has won its chief triumphs in the field of synthesis. Organic chemistry,
that is, the chemistry of the carbon compounds, so called because it was
formerly assumed, as Gerhardt says, that they could only be formed by
"vital force" of organized plants and animals, has taken a development
far overshadowing inorganic chemistry, or the chemistry of mineral
substances. Chemists have prepared or know how to prepare hundreds of
thousands of such "organic compounds," few of which occur in the natural
world.
But this conception of chemistry is yet far from having been accepted by
the world at large. This was brought forcibly to my attention during the
publication of these chapters in "The Independent" by various letters,
raising such objections as the following:
When you say in your article on "What Comes from Coal Tar" that
"Art can go ahead of nature in the dyestuff business" you have
doubtless for the moment allowed your enthusiasm to sweep you
away from the moorings of reason. Shakespeare, anticipating you
and your "Creative Chemistry," has shown the utter
untenableness of your position:
Nature is made better by no mean,
But nature makes that mean: so o'er that art,
Which, you say, adds to nature, is an art
That nature makes.
How can you say that art surpasses nature when you know very
well that nothing man is able to make can in any way equal the
perfection of all nature's products?
It is blasphemous of you to claim that man can improve the
works of God as they appear in nature. Only the Creator can
create. Man only imitates, destroys or defiles God's handiwork.
No, it was not in momentary absence of mind that I claimed that man
could improve upon nature in the making of dyes. I not only said it, but
I proved it. I not only proved it, but I can back it up. I will give a
million dollars to anybody finding in nature dyestuffs as numerous,
varied, brilliant, pure and cheap as those that are manufactured in the
laboratory. I haven't that amount of money with me at the moment, but
the dyers would be glad to put it up for the discovery of a satisfactory
natural source for their tinctorial materials. This is not an opinion of
mine but a matter of fact, not to be decided by Shakespeare, who was not
acquainted with the aniline products.
Shakespeare in the passage quoted is indulging in his favorite amusement
of a play upon words. There is a possible and a proper sense of the word
"nature" that makes it include everything except the supernatural.
Therefore man and all his works belong to the realm of nature. A
tenement house in this sense is as "natural" as a bird's nest, a peapod
or a crystal.
But such a wide extension of the term destroys its distinctive value. It
is more convenient and quite as correct to use "nature" as I have used
it, in contradistinction to "art," meaning by the former the products of
the mineral, vegetable and animal kingdoms, excluding the designs,
inventions and constructions of man which we call "art."
We cannot, in a general and abstract fashion, say which is superior, art
or nature, because it all depends on the point of view. The worm loves a
rotten log into which he can bore. Man prefers a steel cabinet into
which the worm cannot bore. If man cannot improve Upon nature he has no
motive for making anything. Artificial products are therefore superior
to natural products as measured by man's convenience, otherwise they
would have no reason for existence.
Science and Christianity are at one in abhorring the natural man and
calling upon the civilized man to fight and subdue him. The conquest of
nature, not the imitation of nature, is the whole duty of man.
Metchnikoff and St. Paul unite in criticizing the body we were born
with. St. Augustine and Huxley are in agreement as to the eternal
conflict between man and nature. In his Romanes lecture on "Evolution
and Ethics" Huxley said: "The ethical progress of society depends, not
on imitating the cosmic process, still less on running away from it, but
on combating it," and again: "The history of civilization details the
steps by which man has succeeded in building up an artificial world
within the cosmos."
There speaks the true evolutionist, whose one desire is to get away from
nature as fast and far as possible. Imitate Nature? Yes, when we cannot
improve upon her. Admire Nature? Possibly, but be not blinded to her
defects. Learn from Nature? We should sit humbly at her feet until we
can stand erect and go our own way. Love Nature? Never! She is our
treacherous and unsleeping foe, ever to be feared and watched and
circumvented, for at any moment and in spite of all our vigilance she
may wipe out the human race by famine, pestilence or earthquake and
within a few centuries obliterate every trace of its achievement. The
wild beasts that man has kept at bay for a few centuries will in the end
invade his palaces: the moss will envelop his walls and the lichen
disrupt them. The clam may survive man by as many millennia as it
preceded him. In the ultimate devolution of the world animal life will
disappear before vegetable, the higher plants will be killed off before
the lower, and finally the three kingdoms of nature will be reduced to
one, the mineral. Civilized man, enthroned in his citadel and defended
by all the forces of nature that he has brought under his control, is
after all in the same situation as a savage, shivering in the darkness
beside his fire, listening to the pad of predatory feet, the rustle of
serpents and the cry of birds of prey, knowing that only the fire keeps
his enemies off, but knowing too that every stick he lays on the fire
lessens his fuel supply and hastens the inevitable time when the beasts
of the jungle will make their fatal rush.
Chaos is the "natural" state of the universe. Cosmos is the rare and
temporary exception. Of all the million spheres this is apparently the
only one habitable and of this only a small part--the reader may draw
the boundaries to suit himself--can be called civilized. Anarchy is the
natural state of the human race. It prevailed exclusively all over the
world up to some five thousand years ago, since which a few peoples have
for a time succeeded in establishing a certain degree of peace and
order. This, however, can be maintained only by strenuous and persistent
efforts, for society tends naturally to sink into the chaos out of which
it has arisen.
It is only by overcoming nature that man can rise. The sole salvation
for the human race lies in the removal of the primal curse, the sentence
of hard labor for life that was imposed on man as he left Paradise. Some
folks are trying to elevate the laboring classes; some are trying to
keep them down. The scientist has a more radical remedy; he wants to
annihilate the laboring classes by abolishing labor. There is no longer
any need for human labor in the sense of personal toil, for the physical
energy necessary to accomplish all kinds of work may be obtained from
external sources and it can be directed and controlled without extreme
exertion. Man's first effort in this direction was to throw part of his
burden upon the horse and ox or upon other men. But within the last
century it has been discovered that neither human nor animal servitude
is necessary to give man leisure for the higher life, for by means of
the machine he can do the work of giants without exhaustion. But the
introduction of machines, like every other step of human progress, met
with the most violent opposition from those it was to benefit. "Smash
'em!" cried the workingman. "Smash 'em!" cried the poet. "Smash 'em!"
cried the artist. "Smash 'em!" cried the theologian. "Smash 'em!" cried
the magistrate. This opposition yet lingers and every new invention,
especially in chemistry, is greeted with general distrust and often with
legislative prohibition.
Man is the tool-using animal, and the machine, that is, the power-driven
tool, is his peculiar achievement. It is purely a creation of the human
mind. The wheel, its essential feature, does not exist in nature. The
lever, with its to-and-fro motion, we find in the limbs of all animals,
but the continuous and revolving lever, the wheel, cannot be formed of
bone and flesh. Man as a motive power is a poor thing. He can only
convert three or four thousand calories of energy a day and he does that
very inefficiently. But he can make an engine that will handle a hundred
thousand times that, twice as efficiently and three times as long. In
this way only can he get rid of pain and toil and gain the wealth he
wants.
Gradually then he will substitute for the natural world an artificial
world, molded nearer to his heart's desire. Man the Artifex will
ultimately master Nature and reign supreme over his own creation until
chaos shall come again. In the ancient drama it was _deus ex machina_
that came in at the end to solve the problems of the play. It is to the
same supernatural agency, the divinity in machinery, that we must look
for the salvation of society. It is by means of applied science that the
earth can be made habitable and a decent human life made possible.
Creative evolution is at last becoming conscious.
II
NITROGEN
PRESERVER AND DESTROYER OF LIFE
In the eyes of the chemist the Great War was essentially a series of
explosive reactions resulting in the liberation of nitrogen. Nothing
like it has been seen in any previous wars. The first battles were
fought with cellulose, mostly in the form of clubs. The next were fought
with silica, mostly in the form of flint arrowheads and spear-points.
Then came the metals, bronze to begin with and later iron. The
nitrogenous era in warfare began when Friar Roger Bacon or Friar
Schwartz--whichever it was--ground together in his mortar saltpeter,
charcoal and sulfur. The Chinese, to be sure, had invented gunpowder
long before, but they--poor innocents--did not know of anything worse to
do with it than to make it into fire-crackers. With the introduction of
"villainous saltpeter" war ceased to be the vocation of the nobleman and
since the nobleman had no other vocation he began to become extinct. A
bullet fired from a mile away is no respecter of persons. It is just as
likely to kill a knight as a peasant, and a brave man as a coward. You
cannot fence with a cannon ball nor overawe it with a plumed hat. The
only thing you can do is to hide and shoot back. Now you cannot hide if
you send up a column of smoke by day and a pillar of fire by night--the
most conspicuous of signals--every time you shoot. So the next step was
the invention of a smokeless powder. In this the oxygen necessary for
the combustion is already in such close combination with its fuel, the
carbon and hydrogen, that no black particles of carbon can get away
unburnt. In the old-fashioned gunpowder the oxygen necessary for the
combustion of the carbon and sulfur was in a separate package, in the
molecule of potassium nitrate, and however finely the mixture was
ground, some of the atoms, in the excitement of the explosion, failed to
find their proper partners at the moment of dispersal. The new gunpowder
besides being smokeless is ashless. There is no black sticky mass of
potassium salts left to foul the gun barrel.
The gunpowder period of warfare was actively initiated at the battle of
Cressy, in which, as a contemporary historian says, "The English guns
made noise like thunder and caused much loss in men and horses."
Smokeless powder as invented by Paul Vieille was adopted by the French
Government in 1887. This, then, might be called the beginning of the
guncotton or nitrocellulose period--or, perhaps in deference to the
caveman's club, the second cellulose period of human warfare. Better,
doubtless, to call it the "high explosive period," for various other
nitro-compounds besides guncotton are being used.
The important thing to note is that all the explosives from gunpowder
down contain nitrogen as the essential element. It is customary to call
nitrogen "an inert element" because it was hard to get it into
combination with other elements. It might, on the other hand, be looked
upon as an active element because it acts so energetically in getting
out of its compounds. We can dodge the question by saying that nitrogen
is a most unreliable and unsociable element. Like Kipling's cat it walks
by its wild lone.
It is not so bad as Argon the Lazy and the other celibate gases of that
family, where each individual atom goes off by itself and absolutely
refuses to unite even temporarily with any other atom. The nitrogen
atoms will pair off with each other and stick together, but they are
reluctant to associate with other elements and when they do the
combination is likely to break up any moment. You all know people like
that, good enough when by themselves but sure to break up any club,
church or society they get into. Now, the value of nitrogen in warfare
is due to the fact that all the atoms desert in a body on the field of
battle. Millions of them may be lying packed in a gun cartridge, as
quiet as you please, but let a little disturbance start in the
neighborhood--say a grain of mercury fulminate flares up--and all the
nitrogen atoms get to trembling so violently that they cannot be
restrained. The shock spreads rapidly through the whole mass. The
hydrogen and carbon atoms catch up the oxygen and in an instant they are
off on a stampede, crowding in every direction to find an exit, and
getting more heated up all the time. The only movable side is the cannon
ball in front, so they all pound against that and give it such a shove
that it goes ten miles before it stops. The external bombardment by the
cannon ball is, therefore, preceded by an internal bombardment on the
cannon ball by the molecules of the hot gases, whose speed is about as
great as the speed of the projectile that they propel.
[Illustration: © Underwood & Underwood
THE HAND GRENADES WHICH THESE WOMEN ARE BORING will contain potential
chemical energy capable of causing a vast amount of destruction when
released. During the war the American Government placed orders for
68,000,000 such grenades as are here shown.]
[Illustration: © International Film Service, Inc.
WOMEN IN A MUNITION PLANT ENGAGED IN THE MANUFACTURE OF
TRI-NITRO-TOLUOL, THE MOST IMPORTANT OF MODERN HIGH EXPLOSIVES]
The active agent in all these explosives is the nitrogen atom in
combination with two oxygen atoms, which the chemist calls the "nitro
group" and which he represents by NO_{2}. This group was, as I have
said, originally used in the form of saltpeter or potassium nitrate, but
since the chemist did not want the potassium part of it--for it fouled
his guns--he took the nitro group out of the nitrate by means of
sulfuric acid and by the same means hooked it on to some compound of
carbon and hydrogen that would burn without leaving any residue, and
give nothing but gases. One of the simplest of these hydrocarbon
derivatives is glycerin, the same as you use for sunburn. This mixed
with nitric and sulfuric acids gives nitroglycerin, an easy thing to
make, though I should not advise anybody to try making it unless he has
his life insured. But nitroglycerin is uncertain stuff to keep and being
a liquid is awkward to handle. So it was mixed with sawdust or porous
earth or something else that would soak it up. This molded into sticks
is our ordinary dynamite.
If instead of glycerin we take cellulose in the form of wood pulp or
cotton and treat this with nitric acid in the presence of sulfuric we
get nitrocellulose or guncotton, which is the chief ingredient of
smokeless powder.
Now guncotton looks like common cotton. It is too light and loose to
pack well into a gun. So it is dissolved with ether and alcohol or
acetone to make a plastic mass that can be molded into rods and cut into
grains of suitable shape and size to burn at the proper speed.
Here, then, we have a liquid explosive, nitroglycerin, that has to be
soaked up in some porous solid, and a porous solid, guncotton, that has
to soak up some liquid. Why not solve both difficulties together by
dissolving the guncotton in the nitroglycerin and so get a double
explosive? This is a simple idea. Any of us can see the sense of
it--once it is suggested to us. But Alfred Nobel, the Swedish chemist,
who thought it out first in 1878, made millions out of it. Then,
apparently alarmed at the possible consequences of his invention, he
bequeathed the fortune he had made by it to found international prizes
for medical, chemical and physical discoveries, idealistic literature
and the promotion of peace. But his posthumous efforts for the
advancement of civilization and the abolition of war did not amount to
much and his high explosives were later employed to blow into pieces the
doctors, chemists, authors and pacifists he wished to reward.
Nobel's invention, "cordite," is composed of nitroglycerin and
nitrocellulose with a little mineral jelly or vaseline. Besides cordite
and similar mixtures of nitroglycerin and nitrocellulose there are two
other classes of high explosives in common use.
One is made from carbolic acid, which is familiar to us all by its use
as a disinfectant. If this is treated with nitric and sulfuric acids we
get from it picric acid, a yellow crystalline solid. Every government
has its own secret formula for this type of explosive. The British call
theirs "lyddite," the French "melinite" and the Japanese "shimose."
The third kind of high explosives uses as its base toluol. This is not
so familiar to us as glycerin, cotton or carbolic acid. It is one of the
coal tar products, an inflammable liquid, resembling benzene. When
treated with nitric acid in the usual way it takes up like the others
three nitro groups and so becomes tri-nitro-toluol. Realizing that
people could not be expected to use such a mouthful of a word, the
chemists have suggested various pretty nicknames, trotyl, tritol,
trinol, tolite and trilit, but the public, with the wilfulness it always
shows in the matter of names, persists in calling it TNT, as though it
were an author like G.B.S., or G.K.C, or F.P.A. TNT is the latest of
these high explosives and in some ways the best of them. Picric acid has
the bad habit of attacking the metals with which it rests in contact
forming sensitive picrates that are easily set off, but TNT is inert
toward metals and keeps well. TNT melts far below the boiling point of
water so can be readily liquefied and poured into shells. It is
insensitive to ordinary shocks. A rifle bullet can be fired through a
case of it without setting it off, and if lighted with a match it burns
quietly. The amazing thing about these modern explosives, the organic
nitrates, is the way they will stand banging about and burning, yet the
terrific violence with which they blow up when shaken by an explosive
wave of a particular velocity like that of a fulminating cap. Like
picric acid, TNT stains the skin yellow and causes soreness and
sometimes serious cases of poisoning among the employees, mostly girls,
in the munition factories. On the other hand, the girls working with
cordite get to using it as chewing gum; a harmful habit, not because of
any danger of being blown up by it, but because nitroglycerin is a heart
stimulant and they do not need that.
[Illustration: The Genealogical Tree of Nitric Acid From W.Q. Whitman's
"The Story of Nitrates in the War," _General Science Quarterly_]
TNT is by no means smokeless. The German shells that exploded with a
cloud of black smoke and which British soldiers called "Black Marias,"
"coal-boxes" or "Jack Johnsons" were loaded with it. But it is an
advantage to have a shell show where it strikes, although a disadvantage
to have it show where it starts.
It is these high explosives that have revolutionized warfare. As soon as
the first German shell packed with these new nitrates burst inside the
Gruson cupola at Liège and tore out its steel and concrete by the roots
the world knew that the day of the fixed fortress was gone. The armies
deserted their expensively prepared fortifications and took to the
trenches. The British troops in France found their weapons futile and
sent across the Channel the cry of "Send us high explosives or we
perish!" The home Government was slow to heed the appeal, but no
progress was made against the Germans until the Allies had the means to
blast them out of their entrenchments by shells loaded with five hundred
pounds of TNT.
All these explosives are made from nitric acid and this used to be made
from nitrates such as potassium nitrate or saltpeter. But nitrates are
rarely found in large quantities. Napoleon and Lee had a hard time to
scrape up enough saltpeter from the compost heaps, cellars and caves for
their gunpowder, and they did not use as much nitrogen in a whole
campaign as was freed in a few days' cannonading on the Somme. Now there
is one place in the world--and so far as we know one only--where
nitrates are to be found abundantly. This is in a desert on the western
slope of the Andes where ancient guano deposits have decomposed and
there was not enough rain to wash away their salts. Here is a bed two
miles wide, two hundred miles long and five feet deep yielding some
twenty to fifty per cent. of sodium nitrate. The deposit originally
belonged to Peru, but Chile fought her for it and got it in 1881. Here
all countries came to get their nitrates for agriculture and powder
making. Germany was the largest customer and imported 750,000 tons of
Chilean nitrate in 1913, besides using 100,000 tons of other nitrogen
salts. By this means her old, wornout fields were made to yield greater
harvests than our fresh land. Germany and England were like two duelists
buying powder at the same shop. The Chilean Government, pocketing an
export duty that aggregated half a billion dollars, permitted the
saltpeter to be shoveled impartially into British and German ships, and
so two nitrogen atoms, torn from their Pacific home and parted, like
Evangeline and Gabriel, by transportation oversea, may have found
themselves flung into each other's arms from the mouths of opposing
howitzers in the air of Flanders. Goethe could write a romance on such a
theme.
Now the moment war broke out this source of supply was shut off to both
parties, for they blockaded each other. The British fleet closed up the
German ports while the German cruisers in the Pacific took up a position
off the coast of Chile in order to intercept the ships carrying nitrates
to England and France. The Panama Canal, designed to afford relief in
such an emergency, caved in most inopportunely. The British sent a fleet
to the Pacific to clear the nitrate route, but it was outranged and
defeated on November 1, 1914. Then a stronger British fleet was sent
out and smashed the Germans off the Falkland Islands on December 8. But
for seven weeks the nitrate route had been closed while the chemical
reactions on the Marne and Yser were decomposing nitrogen-compounds at
an unheard of rate.
England was now free to get nitrates for her munition factories, but
Germany was still bottled up. She had stored up Chilean nitrates in
anticipation of the war and as soon as it was seen to be coming she
bought all she could get in Europe. But this supply was altogether
inadequate and the war would have come to an end in the first winter if
German chemists had not provided for such a contingency in advance by
working out methods of getting nitrogen from the air. Long ago it was
said that the British ruled the sea and the French the land so that left
nothing to the German but the air. The Germans seem to have taken this
jibe seriously and to have set themselves to make the most of the aerial
realm in order to challenge the British and French in the fields they
had appropriated. They had succeeded so far that the Kaiser when he
declared war might well have considered himself the Prince of the Power
of the Air. He had a fleet of Zeppelins and he had means for the
fixation of nitrogen such as no other nation possessed. The Zeppelins
burst like wind bags, but the nitrogen plants worked and made Germany
independent of Chile not only during the war, but in the time of peace.
Germany during the war used 200,000 tons of nitric acid a year in
explosives, yet her supply of nitrogen is exhaustless.
[Illustration: World production and consumption of fixed inorganic
nitrogen expressed in tons nitrogen
From _The Journal of Industrial and Engineering Chemistry_, March,
1919.]
Nitrogen is free as air. That is the trouble; it is too free. It is
fixed nitrogen that we want and that we are willing to pay for; nitrogen
in combination with some other elements in the form of food or
fertilizer so we can make use of it as we set it free. Fixed nitrogen in
its cheapest form, Chile saltpeter, rose to $250 during the war. Free
nitrogen costs nothing and is good for nothing. If a land-owner has a
right to an expanding pyramid of air above him to the limits of the
atmosphere--as, I believe, the courts have decided in the eaves-dropping
cases--then for every square foot of his ground he owns as much
nitrogen as he could buy for $2500. The air is four-fifths free nitrogen
and if we could absorb it in our lungs as we do the oxygen of the other
fifth a few minutes breathing would give us a full meal. But we let this
free nitrogen all out again through our noses and then go and pay 35
cents a pound for steak or 60 cents a dozen for eggs in order to get
enough combined nitrogen to live on. Though man is immersed in an ocean
of nitrogen, yet he cannot make use of it. He is like Coleridge's
"Ancient Mariner" with "water, water, everywhere, nor any drop to
drink."
Nitrogen is, as Hood said not so truly about gold, "hard to get and hard
to hold." The bacteria that form the nodules on the roots of peas and
beans have the power that man has not of utilizing free nitrogen.
Instead of this quiet inconspicuous process man has to call upon the
lightning when he wants to fix nitrogen. The air contains the oxygen and
nitrogen which it is desired to combine to form nitrates but the atoms
are paired, like to like. Passing an electric spark through the air
breaks up some of these pairs and in the confusion of the shock the
lonely atoms seize on their nearest neighbor and so may get partners of
the other sort. I have seen this same thing happen in a square dance
where somebody made a blunder. It is easy to understand the reaction if
we represent the atoms of oxygen and nitrogen by the initials of their
names in this fashion:
NN + OO --> NO + NO
nitrogen oxygen nitric oxide
The --> represents Jove's thunderbolt, a stroke of artificial
lightning. We see on the left the molecules of oxygen and nitrogen,
before taking the electric treatment, as separate elemental pairs, and
then to the right of the arrow we find them as compound molecules of
nitric oxide. This takes up another atom of oxygen from the air and
becomes NOO, or using a subscript figure to indicate the number of atoms
and so avoid repeating the letter, NO_{2} which is the familiar nitro
group of nitric acid (HO--NO_{2}) and of its salts, the nitrates, and of
its organic compounds, the high explosives. The NO_{2} is a brown and
evil-smelling gas which when dissolved in water (HOH) and further
oxidized is completely converted into nitric acid.
The apparatus which effects this transformation is essentially a
gigantic arc light in a chimney through which a current of hot air is
blown. The more thoroughly the air comes under the action of the
electric arc the more molecules of nitrogen and oxygen will be broken up
and rearranged, but on the other hand if the mixture of gases remains in
the path of the discharge the NO molecules are also broken up and go
back into their original form of NN and OO. So the object is to spread
out the electric arc as widely as possible and then run the air through
it rapidly. In the Schönherr process the electric arc is a spiral flame
twenty-three feet long through which the air streams with a vortex
motion. In the Birkeland-Eyde furnace there is a series of semi-circular
arcs spread out by the repellent force of a powerful electric magnet in
a flaming disc seven feet in diameter with a temperature of 6300° F. In
the Pauling furnace the electrodes between which the current strikes
are two cast iron tubes curving upward and outward like the horns of a
Texas steer and cooled by a stream of water passing through them. These
electric furnaces produce two or three ounces of nitric acid for each
kilowatt-hour of current consumed. Whether they can compete with the
natural nitrates and the products of other processes depends upon how
cheaply they can get their electricity. Before the war there were
several large installations in Norway and elsewhere where abundant water
power was available and now the Norwegians are using half a million
horse power continuously in the fixation of nitrogen and the rest of the
world as much again. The Germans had invested largely in these foreign
oxidation plants, but shortly before the war they had sold out and
turned their attention to other processes not requiring so much
electrical energy, for their country is poorly provided with water
power. The Haber process, that they made most of, is based upon as
simple a reaction as that we have been considering, for it consists in
uniting two elemental gases to make a compound, but the elements in this
case are not nitrogen and oxygen, but nitrogen and hydrogen. This gives
ammonia instead of nitric acid, but ammonia is useful for its own
purposes and it can be converted into nitric acid if this is desired.
The reaction is:
NN + HH + HH + HH --> NHHH + NHHH
Nitrogen hydrogen ammonia
The animals go in two by two, but they come out four by four. Four
molecules of the mixed elements are turned into two molecules and so the
gas shrinks to half its volume. At the same time it acquires an
odor--familiar to us when we are curing a cold--that neither of the
original gases had. The agent that effects the transformation in this
case is not the electric spark--for this would tend to work the reaction
backwards--but uranium, a rare metal, which has the peculiar property of
helping along a reaction while seeming to take no part in it. Such a
substance is called a catalyst. The action of a catalyst is rather
mysterious and whenever we have a mystery we need an analogy. We may,
then, compare the catalyst to what is known as "a good mixer" in
society. You know the sort of man I mean. He may not be brilliant or
especially talkative, but somehow there is always "something doing" at a
picnic or house-party when he is along. The tactful hostess, the salon
leader, is a social catalyst. The trouble with catalysts, either human
or metallic, is that they are rare and that sometimes they get sulky and
won't work if the ingredients they are supposed to mix are unsuitable.
But the uranium, osmium, platinum or whatever metal is used as a
catalyzing agent is expensive and although it is not used up it is
easily "poisoned," as the chemists say, by impurities in the gases. The
nitrogen and the hydrogen for the Haber process must then be prepared
and purified before trying to combine them into ammonia. The nitrogen is
obtained by liquefying air by cold and pressure and then boiling off the
nitrogen at 194° C. The oxygen left is useful for other purposes. The
hydrogen needed is extracted by a similar process of fractional
distillation from "water-gas," the blue-flame burning gas used for
heating. Then the nitrogen and hydrogen, mixed in the proportion of one
to three, as shown in the reaction given above, are compressed to two
hundred atmospheres, heated to 1300° F. and passed over the finely
divided uranium. The stream of gas that comes out contains about four
per cent. of ammonia, which is condensed to a liquid by cooling and the
uncombined hydrogen and nitrogen passed again through the apparatus.
The ammonia can be employed in refrigeration and other ways but if it is
desired to get the nitrogen into the form of nitric acid it has to be
oxidized by the so-called Ostwald process. This is the reaction:
NH_{3} + 4O --> HNO_{3} + H_{2}O
ammonia oxygen nitric acid water
The catalyst used to effect this combination is the metal platinum in
the form of fine wire gauze, since the action takes place only on the
surface. The ammonia gas is mixed with air which supplies the oxygen and
the heated mixture run through the platinum gauze at the rate of several
yards a second. Although the gases come in contact with the platinum
only a five-hundredth part of a second yet eighty-five per cent. is
converted into nitric acid.
The Haber process for the making of ammonia by direct synthesis from its
constituent elements and the supplemental Ostwald process for the
conversion of the ammonia into nitric acid were the salvation of
Germany. As soon as the Germans saw that their dash toward Paris had
been stopped at the Marne they knew that they were in for a long war and
at once made plans for a supply of fixed nitrogen. The chief German dye
factories, the Badische Anilin and Soda-Fabrik, promptly put
$100,000,000 into enlarging its plant and raised its production of
ammonium sulfate from 30,000 to 300,000 tons. One German electrical firm
with aid from the city of Berlin contracted to provide 66,000,000 pounds
of fixed nitrogen a year at a cost of three cents a pound for the next
twenty-five years. The 750,000 tons of Chilean nitrate imported annually
by Germany contained about 116,000 tons of the essential element
nitrogen. The fourteen large plants erected during the war can fix in
the form of nitrates 500,000 tons of nitrogen a year, which is more than
twice the amount needed for internal consumption. So Germany is now not
only independent of the outside world but will have a surplus of
nitrogen products which could be sold even in America at about half what
the farmer has been paying for South American saltpeter.
Besides the Haber or direct process there are other methods of making
ammonia which are, at least outside of Germany, of more importance. Most
prominent of these is the cyanamid process. This requires electrical
power since it starts with a product of the electrical furnace, calcium
carbide, familiar to us all as a source of acetylene gas.
If a stream of nitrogen is passed over hot calcium carbide it is taken
up by the carbide according to the following equation:
CaC_{2} + N_{2} --> CaCN_{2} + C
calcium carbide nitrogen calcium cyanamid carbon
Calcium cyanamid was discovered in 1895 by Caro and Franke when they
were trying to work out a new process for making cyanide to use in
extracting gold. It looks like stone and, under the name of
lime-nitrogen, or Kalkstickstoff, or nitrolim, is sold as a fertilizer.
If it is desired to get ammonia, it is treated with superheated steam.
The reaction produces heat and pressure, so it is necessary to carry it
on in stout autoclaves or enclosed kettles. The cyanamid is completely
and quickly converted into pure ammonia and calcium carbonate, which is
the same as the limestone from which carbide was made. The reaction is:
CaCN_{2} + 3H_{2}O --> CaCO_{3} + 2NH_{3}
calcium cyanamid water calcium carbonate ammonia
Another electrical furnace method, the Serpek process, uses aluminum
instead of calcium for the fixation of nitrogen. Bauxite, or impure
aluminum oxide, the ordinary mineral used in the manufacture of metallic
aluminum, is mixed with coal and heated in a revolving electrical
furnace through which nitrogen is passing. The equation is:
Al_{2}O_{3} + 3C + N_{2} --> 2AlN + 3CO
aluminum carbon nitrogen aluminum carbon
oxide nitride monoxide
Then the aluminum nitride is treated with steam under pressure, which
produces ammonia and gives back the original aluminum oxide, but in a
purer form than the mineral from which was made
2AlN + 3H_{2}O --> 2NH_{3} + Al_{2}O_{3}
Aluminum water ammonia aluminum oxide
nitride
The Serpek process is employed to some extent in France in connection
with the aluminum industry. These are the principal processes for the
fixation of nitrogen now in use, but they by no means exhaust the
possibilities. For instance, Professor John C. Bucher, of Brown
University, created a sensation in 1917 by announcing a new process
which he had worked out with admirable completeness and which has some
very attractive features. It needs no electric power or high pressure
retorts or liquid air apparatus. He simply fills a twenty-foot tube with
briquets made out of soda ash, iron and coke and passes producer gas
through the heated tube. Producer gas contains nitrogen since it is made
by passing air over hot coal. The reaction is:
2Na_{2}CO_{3} + 4C + N_{2} = 2NaCN + 3CO
sodium carbon nitrogen sodium carbon
carbonate cyanide monoxide
The iron here acts as the catalyst and converts two harmless substances,
sodium carbonate, which is common washing soda, and carbon, into two of
the most deadly compounds known to man, cyanide and carbon monoxide,
which is what kills you when you blow out the gas. Sodium cyanide is a
salt of hydrocyanic acid, which for, some curious reason is called
"Prussic acid." It is so violent a poison that, as the freshman said in
a chemistry recitation, "a single drop of it placed on the tongue of a
dog will kill a man."
But sodium cyanide is not only useful in itself, for the extraction of
gold and cleaning of silver, but can be converted into ammonia, and a
variety of other compounds such as urea and oxamid, which are good
fertilizers; sodium ferrocyanide, that makes Prussian blue; and oxalic
acid used in dyeing. Professor Bucher claimed that his furnace could be
set up in a day at a cost of less than $100 and could turn out 150
pounds of sodium cyanide in twenty-four hours. This process was placed
freely at the disposal of the United States Government for the war and a
10-ton plant was built at Saltville, Va., by the Ordnance Department.
But the armistice put a stop to its operations and left the future of
the process undetermined.
[Illustration: A CHEMICAL REACTION ON A LARGE SCALE
From the chemist's standpoint modern warfare consists in the rapid
liberation of nitrogen from its compounds]
[Illustration: Courtesy of E.I. du Pont de Nemours Co.
BURNING AIR IN A BIRKELAND-EYDE FURNACE AT THE DU PONT PLANT
An electric arc consuming about 4000 horse-power of energy is passing
between the U-shaped electrodes which are made of copper tube cooled by
an internal current of water. On the sides of the chamber are seen the
openings through which the air passes impinging directly on both sides
of the surface of the disk of flame. This flame is approximately seven
feet in diameter and appears to be continuous although an alternating
current of fifty cycles a second is used. The electric arc is spread
into this disk flame by the repellent power of an electro-magnet the
pointed pole of which is seen at bottom of the picture. Under this
intense heat a part of the nitrogen and oxygen of the air combine to
form oxides of nitrogen which when dissolved in water form the nitric
acid used in explosives.]
[Illustration: Courtesy of E.I. du Pont de Nemours Co.
A BATTERY OF BIRKELAND-EYDE FURNACES FOR THE FIXATION OF NITROGEN AT THE
DU PONT PLANT]
We might have expected that the fixation of nitrogen by passing an
electrical spark through hot air would have been an American invention,
since it was Franklin who snatched the lightning from the heavens as
well as the scepter from the tyrant and since our output of hot air is
unequaled by any other nation. But little attention was paid to the
nitrogen problem until 1916 when it became evident that we should soon
be drawn into a war "with a first class power." On June 3, 1916,
Congress placed $20,000,000 at the disposal of the president for
investigation of "the best, cheapest and most available means for the
production of nitrate and other products for munitions of war and useful
in the manufacture of fertilizers and other useful products by water
power or any other power." But by the time war was declared on April 6,
1917, no definite program had been approved and by the time the
armistice was signed on November 11, 1918, no plants were in active
operation. But five plants had been started and two of them were nearly
ready to begin work when they were closed by the ending of the war.
United States Nitrate Plant No. 1 was located at Sheffield, Alabama, and
was designed for the production of ammonia by "direct action" from
nitrogen and hydrogen according to the plans of the American Chemical
Company. Its capacity was calculated at 60,000 pounds of anhydrous
ammonia a day, half of which was to be oxidized to nitric acid. Plant
No. 2 was erected at Muscle Shoals, Alabama, to use the process of the
American Cyanamid Company. This was contracted to produce 110,000 tons
of ammonium nitrate a year and later two other cyanamid plants of half
that capacity were started at Toledo and Ancor, Ohio.
At Muscle Shoals a mushroom city of 20,000 sprang up on an Alabama
cotton field in six months. The raw material, air, was as abundant there
as anywhere and the power, water, could be obtained from the Government
hydro-electric plant on the Tennessee River, but this was not available
during the war, so steam was employed instead. The heat of the coal was
used to cool the air down to the liquefying point. The principle of this
process is simple. Everybody knows that heat expands and cold contracts,
but not everybody has realized the converse of this rule, that expansion
cools and compression heats. If air is forced into smaller space, as in
a tire pump, it heats up and if allowed to expand to ordinary pressure
it cools off again. But if the air while compressed is cooled and then
allowed to expand it must get still colder and the process can go on
till it becomes cold enough to congeal. That is, by expanding a great
deal of air, a little of it can be reduced to the liquefying point. At
Muscle Shoals the plant for liquefying air, in order to get the nitrogen
out of it, consisted of two dozen towers each capable of producing 1765
cubic feet of pure nitrogen per hour. The air was drawn in through two
pipes, a yard across, and passed through scrubbing towers to remove
impurities. The air was then compressed to 600 pounds per square inch.
Nine tenths of the air was permitted to expand to 50 pounds and this
expansion cooled down the other tenth, still under high pressure, to the
liquefying point. Rectifying towers 24 feet high were stacked with trays
of liquid air from which the nitrogen was continually bubbling off since
its boiling point is twelve degrees centigrade lower than that of
oxygen. Pure nitrogen gas collected at the top of the tower and the
residual liquid air, now about half oxygen, was allowed to escape at the
bottom.
The nitrogen was then run through pipes into the lime-nitrogen ovens.
There were 1536 of these about four feet square and each holding 1600
pounds of pulverized calcium carbide. This is at first heated by an
electrical current to start the reaction which afterwards produces
enough heat to keep it going. As the stream of nitrogen gas passes over
the finely divided carbide it is absorbed to form calcium cyanamid as
described on a previous page. This product is cooled, powdered and wet
to destroy any quicklime or carbide left unchanged. Then it is charged
into autoclaves and steam at high temperature and pressure is admitted.
The steam acting on the cyanamid sets free ammonia gas which is carried
to towers down which cold water is sprayed, giving the ammonia water,
familiar to the kitchen and the bathroom.
But since nitric acid rather than ammonia was needed for munitions, the
oxygen of the air had to be called into play. This process, as already
explained, is carried on by aid of a catalyzer, in this case platinum
wire. At Muscle Shoals there were 696 of these catalyzer boxes. The
ammonia gas, mixed with air to provide the necessary oxygen, was
admitted at the top and passed down through a sheet of platinum gauze of
80 mesh to the inch, heated to incandescence by electricity. In contact
with this the ammonia is converted into gaseous oxides of nitrogen (the
familiar red fumes of the laboratory) which, carried off in pipes,
cooled and dissolved in water, form nitric acid.
But since none of the national plants could be got into action during
the war, the United States was compelled to draw upon South America for
its supply. The imports of Chilean saltpeter rose from half a million
tons in 1914 to a million and a half in 1917. After peace was made the
Department of War turned over to the Department of Agriculture its
surplus of saltpeter, 150,000 tons, and it was sold to American farmers
at cost, $81 a ton.
For nitrogen plays a double rôle in human economy. It appears like
Brahma in two aspects, Vishnu the Preserver and Siva the Destroyer. Here
I have been considering nitrogen in its maleficent aspect, its use in
war. We now turn to its beneficent aspect, its use in peace.
III
FEEDING THE SOIL
The Great War not only starved people: it starved the land. Enough
nitrogen was thrown away in some indecisive battle on the Aisne to save
India from a famine. The population of Europe as a whole has not been
lessened by the war, but the soil has been robbed of its power to
support the population. A plant requires certain chemical elements for
its growth and all of these must be within reach of its rootlets, for it
will accept no substitutes. A wheat stalk in France before the war had
placed at its feet nitrates from Chile, phosphates from Florida and
potash from Germany. All these were shut off by the firing line and the
shortage of shipping.
Out of the eighty elements only thirteen are necessary for crops. Four
of these are gases: hydrogen, oxygen, nitrogen and chlorine. Five are
metals: potassium, magnesium, calcium, iron and sodium. Four are
non-metallic solids: carbon, sulfur, phosphorus and silicon. Three of
these, hydrogen, oxygen and carbon, making up the bulk of the plant, are
obtainable _ad libitum_ from the air and water. The other ten in the
form of salts are dissolved in the water that is sucked up from the
soil. The quantity needed by the plant is so small and the quantity
contained in the soil is so great that ordinarily we need not bother
about the supply except in case of three of them. They are nitrogen,
potassium and phosphorus. These would be useless or fatal to plant life
in the elemental form, but fixed in neutral salt they are essential
plant foods. A ton of wheat takes away from the soil about 47 pounds of
nitrogen, 18 pounds of phosphoric acid and 12 pounds of potash. If then
the farmer does not restore this much to his field every year he is
drawing upon his capital and this must lead to bankruptcy in the long
run.
So much is easy to see, but actually the question is extremely
complicated. When the German chemist, Justus von Liebig, pointed out in
1840 the possibility of maintaining soil fertility by the application of
chemicals it seemed at first as though the question were practically
solved. Chemists assumed that all they had to do was to analyze the soil
and analyze the crop and from this figure out, as easily as balancing a
bank book, just how much of each ingredient would have to be restored to
the soil every year. But somehow it did not work out that way and the
practical agriculturist, finding that the formulas did not fit his farm,
sneered at the professors and whenever they cited Liebig to him he
irreverently transposed the syllables of the name. The chemist when he
went deeper into the subject saw that he had to deal with the colloids,
damp, unpleasant, gummy bodies that he had hitherto fought shy of
because they would not crystallize or filter. So the chemist called to
his aid the physicist on the one hand and the biologist on the other and
then they both had their hands full. The physicist found that he had to
deal with a polyvariant system of solids, liquids and gases mutually
miscible in phases too numerous to be handled by Gibbs's Rule. The
biologist found that he had to deal with the invisible flora and fauna
of a new world.
Plants obey the injunction of Tennyson and rise on the stepping stones
of their dead selves to higher things. Each successive generation lives
on what is left of the last in the soil plus what it adds from the air
and sunshine. As soon as a leaf or tree trunk falls to the ground it is
taken in charge by a wrecking crew composed of a myriad of microscopic
organisms who proceed to break it up into its component parts so these
can be used for building a new edifice. The process is called "rotting"
and the product, the black, gummy stuff of a fertile soil, is called
"humus." The plants, that is, the higher plants, are not able to live on
their own proteids as the animals are. But there are lower plants,
certain kinds of bacteria, that can break up the big complicated proteid
molecules into their component parts and reduce the nitrogen in them to
ammonia or ammonia-like compounds. Having done this they stop and turn
over the job to another set of bacteria to be carried through the next
step. For you must know that soil society is as complex and specialized
as that above ground and the tiniest bacterium would die rather than
violate the union rules. The second set of bacteria change the ammonia
over to nitrites and then a third set, the Amalgamated Union of Nitrate
Workers, steps in and completes the process of oxidation with an
efficiency that Ostwald might envy, for ninety-six per cent. of the
ammonia of the soil is converted into nitrates. But if the conditions
are not just right, if the food is insufficient or unwholesome or if
the air that circulates through the soil is contaminated with poison
gases, the bacteria go on a strike. The farmer, not seeing the thing
from the standpoint of the bacteria, says the soil is "sick" and he
proceeds to doctor it according to his own notion of what ails it. First
perhaps he tries running in strike breakers. He goes to one of the firms
that makes a business of supplying nitrogen-fixing bacteria from the
scabs or nodules of the clover roots and scatters these colonies over
the field. But if the living conditions remain bad the newcomers will
soon quit work too and the farmer loses his money. If he is wise, then,
he will remedy the conditions, putting a better ventilation system in
his soil perhaps or neutralizing the sourness by means of lime or
killing off the ameboid banditti that prey upon the peaceful bacteria
engaged in the nitrogen industry. It is not an easy job that the farmer
has in keeping billions of billions of subterranean servants contented
and working together, but if he does not succeed at this he wastes his
seed and labor.
The layman regards the soil as a platform or anchoring place on which to
set plants. He measures its value by its superficial area without
considering its contents, which is as absurd as to estimate a man's
wealth by the size of his safe. The difference in point of view is well
illustrated by the old story of the city chap who was showing his farmer
uncle the sights of New York. When he took him to Central Park he tried
to astonish him by saying "This land is worth $500,000 an acre." The old
farmer dug his toe into the ground, kicked out a clod, broke it open,
looked at it, spit on it and squeezed it in his hand and then said,
"Don't you believe it; 'tain't worth ten dollars an acre. Mighty poor
soil I call it." Both were right.
[Illustration: Courtesy of American Cyanamid Co.
FIXING NITROGEN BY CALCIUM CARBIDE
A view of the oven room in the plant of the American Cyanamid Company.
The steel cylinders standing in the background are packed with the
carbide and then put into the ovens sunk in the floor. When these are
heated internally by electricity to 2000 degrees Fahrenheit pure
nitrogen is let in and absorbed by the carbide, making cyanamid, which
may be used as a fertilizer or for ammonia.]
[Illustration: Photo by International Film Service
A BARROW FULL OF POTASH SALTS EXTRACTED FROM SIX TONS OF GREEN KELP BY
THE GOVERNMENT CHEMISTS]
[Illustration: NATURE'S SILENT METHOD OF NITROGEN FIXATION
The nodules on the vetch roots contain colonies of bacteria which have
the power of taking the free nitrogen out of the air and putting it in
compounds suitable for plant food.]
The modern agriculturist realizes that the soil is a laboratory for the
production of plant food and he ordinarily takes more pains to provide a
balanced ration for it than he does for his family. Of course the
necessity of feeding the soil has been known ever since man began to
settle down and the ancient methods of maintaining its fertility, though
discovered accidentally and followed blindly, were sound and
efficacious. Virgil, who like Liberty Hyde Bailey was fond of publishing
agricultural bulletins in poetry, wrote two thousand years ago:
But sweet vicissitudes of rest and toil
Make easy labor and renew the soil
Yet sprinkle sordid ashes all around
And load with fatt'ning dung thy fallow soil.
The ashes supplied the potash and the dung the nitrate and phosphate.
Long before the discovery of the nitrogen-fixing bacteria, the custom
prevailed of sowing pea-like plants every third year and then plowing
them under to enrich the soil. But such local supplies were always
inadequate and as soon as deposits of fertilizers were discovered
anywhere in the world they were drawn upon. The richest of these was the
Chincha Islands off the coast of Peru, where millions of penguins and
pelicans had lived in a most untidy manner for untold centuries. The
guano composed of the excrement of the birds mixed with the remains of
dead birds and the fishes they fed upon was piled up to a depth of 120
feet. From this Isle of Penguins--which is not that described by Anatole
France--a billion dollars' worth of guano was taken and the deposit was
soon exhausted.
Then the attention of the world was directed to the mainland of Peru and
Chile, where similar guano deposits had been accumulated and, not being
washed away on account of the lack of rain, had been deposited as sodium
nitrate, or "saltpeter." These beds were discovered by a German, Taddeo
Haenke, in 1809, but it was not until the last quarter of the century
that the nitrates came into common use as a fertilizer. Since then more
than 53,000,000 tons have been taken out of these beds and the
exportation has risen to a rate of 2,500,000 to 3,000,000 tons a year.
How much longer they will last is a matter of opinion and opinion is
largely influenced by whether you have your money invested in Chilean
nitrate stock or in one of the new synthetic processes for making
nitrates. The United States Department of Agriculture says the nitrate
beds will be exhausted in a few years. On the other hand the Chilean
Inspector General of Nitrate Deposits in his latest official report says
that they will last for two hundred years at the present rate and that
then there are incalculable areas of low grade deposits, containing less
than eleven per cent., to be drawn upon.
Anyhow, the South American beds cannot long supply the world's need of
nitrates and we shall some time be starving unless creative chemistry
comes to the rescue. In 1898 Sir William Crookes--the discoverer of the
"Crookes tubes," the radiometer and radiant matter--startled the British
Association for the Advancement of Science by declaring that the world
was nearing the limit of wheat production and that by 1931 the
bread-eaters, the Caucasians, would have to turn to other grains or
restrict their population while the rice and millet eaters of Asia would
continue to increase. Sir William was laughed at then as a
sensationalist. He was, but his sensations were apt to prove true and it
is already evident that he was too near right for comfort. Before we
were half way to the date he set we had two wheatless days a week,
though that was because we persisted in shooting nitrates into the air.
The area producing wheat was by decades:[1]
THE WHEAT FIELDS OF THE WORLD
Acres
1881-90 192,000,000
1890-1900 211,000,000
1900-10 242,000,000
Probable limit 300,000,000
If 300,000,000 acres can be brought under cultivation for wheat and the
average yield raised to twenty bushels to the acre, that will give
enough to feed a billion people if they eat six bushels a year as do the
English. Whether this maximum is correct or not there is evidently some
limit to the area which has suitable soil and climate for growing wheat,
so we are ultimately thrown back upon Crookes's solution of the problem;
that is, we must increase the yield per acre and this can only be done
by the use of fertilizers and especially by the fixation of atmospheric
nitrogen. Crookes estimated the average yield of wheat at 12.7 bushels
to the acre, which is more than it is in the new lands of the United
States, Australia and Russia, but less than in Europe, where the soil is
well fed. What can be done to increase the yield may be seen from these
figures:
GAIN IN THE YIELD OF WHEAT IN BUSHELS PER ACRE
1889-90 1913
Germany 19 35
Belgium 30 35
France 17 20
United Kingdom 28 32
United States 12 15
The greatest gain was made in Germany and we see a reason for it in the
fact that the German importation of Chilean saltpeter was 55,000 tons in
1880 and 747,000 tons in 1913. In potatoes, too, Germany gets twice as
big a crop from the same ground as we do, 223 bushels per acre instead
of our 113 bushels. But the United States uses on the average only 28
pounds of fertilizer per acre, while Europe uses 200.
It is clear that we cannot rely upon Chile, but make nitrates for
ourselves as Germany had to in war time. In the first chapter we
considered the new methods of fixing the free nitrogen from the air. But
the fixation of nitrogen is a new business in this country and our chief
reliance so far has been the coke ovens. When coal is heated in retorts
or ovens for making coke or gas a lot of ammonia comes off with the
other products of decomposition and is caught in the sulfuric acid used
to wash the gas as ammonium sulfate. Our American coke-makers have been
in the habit of letting this escape into the air and consequently we
have been losing some 700,000 tons of ammonium salts every year, enough
to keep our land rich and give us all the explosives we should need. But
now they are reforming and putting in ovens that save the by-products
such as ammonia and coal tar, so in 1916 we got from this source 325,000
tons a year.
[Illustration: Courtesy of _Scientific American_.
Consumption of potash for agricultural purposes in different countries]
Germany had a natural monopoly of potash as Chile had a natural monopoly
of nitrates. The agriculture of Europe and America has been virtually
dependent upon these two sources of plant foods. Now when the world was
cleft in twain by the shock of August, 1914, the Allied Powers had the
nitrates and the Central Powers had the potash. If Germany had not had
up her sleeve a new process for making nitrates she could not long have
carried on a war and doubtless would not have ventured upon it. But the
outside world had no such substitute for the German potash salts and
has not yet discovered one. Consequently the price of potash in the
United States jumped from $40 to $400 and the cost of food went up with
it. Even under the stimulus of prices ten times the normal and with
chemists searching furnace crannies and bad lands the United States was
able to scrape up less than 10,000 tons of potash in 1916, and this was
barely enough to satisfy our needs for two weeks!
[Illustration: What happened to potash when the war broke out. This
diagram from the _Journal of Industrial and Engineering Chemistry_ of
July, 1917, shows how the supply of potassium muriate from Germany was
shut off in 1914 and how its price rose.]
Yet potash compounds are as cheap as dirt. Pick up a handful of gravel
and you will be able to find much of it feldspar or other mineral
containing some ten per cent. of potash. Unfortunately it is in
combination with silica, which is harder to break up than a trust.
But "constant washing wears away stones" and the potash that the
metallurgist finds too hard to extract in his hottest furnace is washed
out in the course of time through the dropping of the gentle rain from
heaven. "All rivers run to the sea" and so the sea gets salt, all sorts
of salts, principally sodium chloride (our table salt) and next
magnesium, calcium and potassium chlorides or sulfates in this order of
abundance. But if we evaporate sea-water down to dryness all these are
left in a mix together and it is hard to sort them out. Only patient
Nature has time for it and she only did on a large scale in one place,
that is at Stassfurt, Germany. It seems that in the days when
northwestern Prussia was undetermined whether it should be sea or land
it was flooded annually by sea-water. As this slowly evaporated the
dissolved salts crystallized out at the critical points, leaving beds of
various combinations. Each year there would be deposited three to five
inches of salts with a thin layer of calcium sulfate or gypsum on top.
Counting these annual layers, like the rings on a stump, we find that
the Stassfurt beds were ten thousand years in the making. They were
first worked for their salt, common salt, alone, but in 1837 the
Prussian Government began prospecting for new and deeper deposits and
found, not the clean rock salt that they wanted, but bittern, largely
magnesium sulfate or Epsom salt, which is not at all nice for table use.
This stuff was first thrown away until it was realized that it was much
more valuable for the potash it contains than was the rock salt they
were after. Then the Germans began to purify the Stassfurt salts and
market them throughout the world. They contain from fifteen to
twenty-five per cent. of magnesium chloride mixed with magnesium
chloride in "carnallite," with magnesium sulfate in "kainite" and sodium
chloride in "sylvinite." More than thirty thousand miners and workmen
are employed in the Stassfurt works. There are some seventy distinct
establishments engaged in the business, but they are in combination. In
fact they are compelled to be, for the German Government is as anxious
to promote trusts as the American Government is to prevent them. Once
the Stassfurt firms had a falling out and began a cutthroat competition.
But the German Government objects to its people cutting each other's
throats. American dealers were getting unheard of bargains when the
German Government stepped in and compelled the competing corporations to
recombine under threat of putting on an export duty that would eat up
their profits.
The advantages of such business coöperation are specially shown in
opening up a new market for an unknown product as in the case of the
introduction of the Stassfurt salts into American agriculture. The
farmer in any country is apt to be set in his ways and when it comes to
inducing him to spend his hard-earned money for chemicals that he never
heard of and could not pronounce he--quite rightly--has to be shown.
Well, he was shown. It was, if I remember right, early in the nineties
that the German Kali Syndikat began operations in America and the United
States Government became its chief advertising agent. In every state
there was an agricultural experiment station and these were provided
liberally with illustrated literature on Stassfurt salts with colored
wall charts and sets of samples and free sacks of salts for field
experiments. The station men, finding that they could rely upon the
scientific accuracy of the information supplied by Kali and that the
experiments worked out well, became enthusiastic advocates of potash
fertilizers. The station bulletins--which Uncle Sam was kind enough to
carry free to all the farmers of the state--sometimes were worded so
like the Kali Company advertising that the company might have raised a
complaint of plagiarizing, but they never did. The Chilean nitrates,
which are under British control, were later introduced by similar
methods through the agency of the state agricultural experiment
stations.
As a result of all this missionary work, which cost the Kali Company
$50,000 a year, the attention of a large proportion of American farmers
was turned toward intensive farming and they began to realize the
necessity of feeding the soil that was feeding them. They grew dependent
upon these two foreign and widely separated sources of supply. In the
year before the war the United States imported a million tons of
Stassfurt salts, for which the farmers paid more than $20,000,000. Then
a declaration of American independence--the German embargo of 1915--cut
us off from Stassfurt and for five years we had to rely upon our own
resources. We have seen how Germany--shut off from Chile--solved the
nitrogen problem for her fields and munition plants. It was not so easy
for us--shut off from Germany--to solve the potash problem.
There is no more lack of potash in the rocks than there is of nitrogen
in the air, but the nitrogen is free and has only to be caught and
combined, while the potash is shut up in a granite prison from which it
is hard to get it free. It is not the percentage in the soil but the
percentage in the soil water that counts. A farmer with his potash
locked up in silicates is like the merchant who has left the key of his
safe at home in his other trousers. He may be solvent, but he cannot
meet a sight draft. It is only solvent potash that passes current.
In the days of our grandfathers we had not only national independence
but household independence. Every homestead had its own potash plant and
soap factory. The frugal housewife dumped the maple wood ashes of the
fireplace into a hollow log set up on end in the backyard. Water poured
over the ashes leached out the lye, which drained into a bucket beneath.
This gave her a solution of pearl ash or potassium carbonate whose
concentration she tested with an egg as a hydrometer. In the meantime
she had been saving up all the waste grease from the frying pan and pork
rinds from the plate and by trying out these she got her soap fat. Then
on a day set apart for this disagreeable process in chemical technology
she boiled the fat and the lye together and got "soft soap," or as the
chemist would call it, potassium stearate. If she wanted hard soap she
"salted it out" with brine. The sodium stearate being less soluble was
precipitated to the top and cooled into a solid cake that could be cut
into bars by pack thread. But the frugal housewife threw away in the
waste water what we now consider the most valuable ingredients, the
potash and the glycerin.
But the old lye-leach is only to be found in ruins on an abandoned farm
and we no longer burn wood at the rate of a log a night. In 1916 even
under the stimulus of tenfold prices the amount of potash produced as
pearl ash was only 412 tons--and we need 300,000 tons in some form. It
would, of course, be very desirable as a conservation measure if all the
sawdust and waste wood were utilized by charring it in retorts. The gas
makes a handy fuel. The tar washed from the gas contains a lot of
valuable products. And potash can be leached out of the charcoal or from
its ashes whenever it is burned. But this at best would not go far
toward solving the problem of our national supply.
There are other potash-bearing wastes that might be utilized. The cement
mills which use feldspar in combination with limestone give off a potash
dust, very much to the annoyance of their neighbors. This can be
collected by running the furnace clouds into large settling chambers or
long flues, where the dust may be caught in bags, or washed out by water
sprays or thrown down by electricity. The blast furnaces for iron also
throw off potash-bearing fumes.
Our six-million-ton crop of sugar beets contains some 12,000 tons of
nitrogen, 4000 tons of phosphoric acid and 18,000 tons of potash, all of
which is lost except where the waste liquors from the sugar factory are
used in irrigating the beet land. The beet molasses, after extracting
all the sugar possible by means of lime, leaves a waste liquor from
which the potash can be recovered by evaporation and charring and
leaching the residue. The Germans get 5000 tons of potassium cyanide and
as much ammonium sulfate annually from the waste liquor of their beet
sugar factories and if it pays them to save this it ought to pay us
where potash is dearer. Various other industries can put in a bit when
Uncle Sam passes around the contribution basket marked "Potash for the
Poor." Wool wastes and fish refuse make valuable fertilizers, although
they will not go far toward solving the problem. If we saved all our
potash by-products they would not supply more than fifteen per cent. of
our needs.
Though no potash beds comparable to those of Stassfurt have yet been
discovered in the United States, yet in Nebraska, Utah, California and
other western states there are a number of alkali lakes, wet or dry,
containing a considerable amount of potash mixed with soda salts. Of
these deposits the largest is Searles Lake, California. Here there are
some twelve square miles of salt crust some seventy feet deep and the
brine as pumped out contains about four per cent. of potassium chloride.
The quantity is sufficient to supply the country for over twenty years,
but it is not an easy or cheap job to separate the potassium from the
sodium salts which are five times more abundant. These being less
soluble than the potassium salts crystallize out first when the brine is
evaporated. The final crystallization is done in vacuum pans as in
getting sugar from the cane juice. In this way the American Trona
Corporation is producing some 4500 tons of potash salts a month besides
a thousand tons of borax. The borax which is contained in the brine to
the extent of 1-1/2 per cent. is removed from the fertilizer for a
double reason. It is salable by itself and it is detrimental to plant
life.
Another mineral source of potash is alunite, which is a sort of natural
alum, or double sulfate of potassium and aluminum, with about ten per
cent. of potash. It contains a lot of extra alumina, but after roasting
in a kiln the potassium sulfate can be leached out. The alunite beds
near Marysville, Utah, were worked for all they were worth during the
war, but the process does not give potash cheap enough for our needs in
ordinary times.
[Illustration: Photo by International Film Service
IN ORDER TO SECURE A NEW SUPPLY OF POTASH SALTS
The United States Government set up an experimental plant at Sutherland,
California, for the utilization of kelp. The harvester cuts 40 tons of
kelp at a load]
[Illustration: THE KELP HARVESTER GATHERING THE SEAWEED FROM THE
PACIFIC OCEAN]
[Illustration: Courtesy of Hercules Powder Co.
OVERHEAD SUCTION AT THE SAN DIEGO WHARF PUMPING KELP FROM THE BARGE TO
THE DIGESTION TANKS]
The tourist going through Wyoming on the Union Pacific will have to the
north of him what is marked on the map as the "Leucite Hills." If he
looks up the word in the Unabridged that he carries in his satchel he
will find that leucite is a kind of lava and that it contains potash.
But he will also observe that the potash is combined with alumina and
silica, which are hard to get out and useless when you get them out. One
of the lavas of the Leucite Hills, that named from its native state
"Wyomingite," gives fifty-seven per cent. of its potash in a soluble
form on roasting with alunite--but this costs too much. The same may be
said of all the potash feldspars and mica. They are abundant enough, but
until we find a way of utilizing the by-products, say the silica in
cement and the aluminum as a metal, they cannot solve our problem.
Since it is so hard to get potash from the land it has been suggested
that we harvest the sea. The experts of the United States Department of
Agriculture have placed high hopes in the kelp or giant seaweed which
floats in great masses in the Pacific Ocean not far off from the
California coast. This is harvested with ocean reapers run by gasoline
engines and brought in barges to the shore, where it may be dried and
used locally as a fertilizer or burned and the potassium chloride
leached out of the charcoal ashes. But it is hard to handle the bulky,
slimy seaweed cheaply enough to get out of it the small amount of potash
it contains. So efforts are now being made to get more out of the kelp
than the potash. Instead of burning the seaweed it is fermented in vats
producing acetic acid (vinegar). From the resulting liquid can be
obtained lime acetate, potassium chloride, potassium iodide, acetone,
ethyl acetate (used as a solvent for guncotton) and algin, a
gelatin-like gum.
PRODUCTION OF POTASH IN THE UNITED STATES
__________________________________________________________________________
| |
| 1916 | 1917
Source | Tons K_{2}O | Per cent. | Tons K_{2}O | Per cent.
| | of total | | of total
| | production | | production
____________________|_____________|____________|_____________|____________
| | | |
Mineral sources: | | | |
Natural brines | 3,994 | 41.1 | 20,652 | 63.4
Altmite | 1,850 | 19.0 | 2,402 | 7.3
Dust from cement | | | |
mills | | | 1,621 | 5.0
Dust from blast | | | |
furnaces | | | 185 | 0.6
Organic Sources: | | | |
Kelp | 1,556 | 16.0 | 3,752 | 10.9
Molasses residue | | | |
from distillers | 1,845 | 19.0 | 2,846 | 8.8
Wood ashes | 412 | 4.2 | 621 | 1.9
Waste liquors | | | |
from beet-sugar | | | |
refineries | | | 369 | 1.1
Miscellaneous | | | |
industrial | | | |
wastes | 63 | .7 | 305 | 1.0
| ___________ | __________ | ___________ | __________
| | | |
Total | 9,720 | 100.0 | 32,573 | 100.0
--From U S. Bureau of Mines Report, 1918.
This table shows how inadequate was the reaction of the United States to
the war demand for potassium salts. The minimum yearly requirements of
the United States are estimated to be 250,000 tons of potash.
This completes our survey of the visible sources of potash in America.
In 1917 under the pressure of the embargo and unprecedented prices the
output of potash (K_{2}O) in various forms was raised to 32,573 tons,
but this is only about a tenth as much as we needed. In 1918 potash
production was further raised to 52,135 tons, chiefly through the
increase of the output from natural brines to 39,255 tons, nearly twice
what it was the year before. The rust in cotton and the resulting
decrease in yield during the war are laid to lack of potash. Truck crops
grown in soils deficient in potash do not stand transportation well. The
Bureau of Animal Industry has shown in experiments in Aroostook County,
Maine, that the addition of moderate amounts of potash doubled the yield
of potatoes.
Professor Ostwald, the great Leipzig chemist, boasted in the war:
America went into the war like a man with a rope round his neck
which is in his enemy's hands and is pretty tightly drawn. With
its tremendous deposits Germany has a world monopoly in potash,
a point of immense value which cannot be reckoned too highly
when once this war is going to be settled. It is in Germany's
power to dictate which of the nations shall have plenty of food
and which shall starve.
If, indeed, some mineralogist or metallurgist will cut that rope by
showing us a supply of cheap potash we will erect him a monument as big
as Washington's. But Ostwald is wrong in supposing that America is as
dependent as Germany upon potash. The bulk of our food crops are at
present raised without the use of any fertilizers whatever.
As the cession of Lorraine in 1871 gave Germany the phosphates she
needed for fertilizers so the retrocession of Alsace in 1919 gives
France the potash she needed for fertilizers. Ten years before the war a
bed of potash was discovered in the Forest of Monnebruck, near
Hartmannsweilerkopf, the peak for which French and Germans contested so
fiercely and so long. The layer of potassium salts is 16-1/2 feet thick
and the total deposit is estimated to be 275,000,000 tons of potash. At
any rate it is a formidable rival of Stassfurt and its acquisition by
France breaks the German monopoly.
When we turn to the consideration of the third plant food we feel
better. While the United States has no such monopoly of phosphates as
Germany had of potash and Chile had of nitrates we have an abundance and
to spare. Whereas we formerly _imported_ about $17,000,000 worth of
potash from Germany and $20,000,000 worth of nitrates from Chile a year
we _exported_ $7,000,000 worth of phosphates.
Whoever it was who first noticed that the grass grew thicker around a
buried bone he lived so long ago that we cannot do honor to his powers
of observation, but ever since then--whenever it was--old bones have
been used as a fertilizer. But we long ago used up all the buffalo bones
we could find on the prairies and our packing houses could not give us
enough bone-meal to go around, so we have had to draw upon the old
bone-yards of prehistoric animals. Deposits of lime phosphate of such
origin were found in South Carolina in 1870 and in Florida in 1888.
Since then the industry has developed with amazing rapidity until in
1913 the United States produced over three million tons of phosphates,
nearly half of which was sent abroad. The chief source at present is the
Florida pebbles, which are dredged up from the bottoms of lakes and
rivers or washed out from the banks of streams by a hydraulic jet. The
gravel is washed free from the sand and clay, screened and dried, and
then is ready for shipment. The rock deposits of Florida and South
Carolina are more limited than the pebble beds and may be exhausted in
twenty-five or thirty years, but Tennessee and Kentucky have a lot in
reserve and behind them are Idaho, Wyoming and other western states with
millions of acres of phosphate land, so in this respect we are
independent.
But even here the war hit us hard. For the calcium phosphate as it comes
from the ground is not altogether available because it is not very
soluble and the plants can only use what they can get in the water that
they suck up from the soil. But if the phosphate is treated with
sulfuric acid it becomes more soluble and this product is sold as
"superphosphate." The sulfuric acid is made mostly from iron pyrite and
this we have been content to import, over 800,000 tons of it a year,
largely from Spain, although we have an abundance at home. Since the
shortage of shipping shut off the foreign supply we are using more of
our own pyrite and also our deposits of native sulfur along the Gulf
coast. But as a consequence of this sulfuric acid during the war went up
from $5 to $25 a ton and acidulated phosphates rose correspondingly.
Germany is short on natural phosphates as she is long on natural potash.
But she has made up for it by utilizing a by-product of her steelworks.
When phosphorus occurs in iron ore, even in minute amounts, it makes the
steel brittle. Much of the iron ores of Alsace-Lorraine were formerly
considered unworkable because of this impurity, but shortly after
Germany took these provinces from France in 1871 a method was discovered
by two British metallurgists, Thomas and Gilchrist, by which the
phosphorus is removed from the iron in the process of converting it into
steel. This consists in lining the crucible or converter with lime and
magnesia, which takes up the phosphorus from the melted iron. This slag
lining, now rich in phosphates, can be taken out and ground up for
fertilizer. So the phosphorus which used to be a detriment is now an
additional source of profit and this British invention has enabled
Germany to make use of the territory she stole from France to outstrip
England in the steel business. In 1910 Germany produced 2,000,000 tons
of Thomas slag while only 160,000 tons were produced in the United
Kingdom. The open hearth process now chiefly used in the United States
gives an acid instead of a basic phosphate slag, not suitable as a
fertilizer. The iron ore of America, with the exception of some of the
southern ores, carries so small a percentage of phosphorus as to make a
basic process inadvisable.
Recently the Germans have been experimenting with a combined fertilizer,
Schröder's potassium phosphate, which is said to be as good as Thomas
slag for phosphates and as good as Stassfurt salts for potash. The
American Cyanamid Company is just putting out a similar product,
"Ammo-Phos," in which the ammonia can be varied from thirteen to twenty
per cent. and the phosphoric acid from twenty to forty-seven per cent.
so as to give the proportions desired for any crop. We have then the
possibility of getting the three essential plant foods altogether in
one compound with the elimination of most of the extraneous elements
such as lime and magnesia, chlorids and sulfates.
For the last three hundred years the American people have been living on
the unearned increment of the unoccupied land. But now that all our land
has been staked out in homesteads and we cannot turn to new soil when we
have used up the old, we must learn, as the older races have learned,
how to keep up the supply of plant food. Only in this way can our
population increase and prosper. As we have seen, the phosphate question
need not bother us and we can see our way clear toward solving the
nitrate question. We gave the Government $20,000,000 to experiment on
the production of nitrates from the air and the results will serve for
fields as well as firearms. But the question of an independent supply of
cheap potash is still unsolved.
IV
COAL-TAR COLORS
If you put a bit of soft coal into a test tube (or, if you haven't a
test tube, into a clay tobacco pipe and lute it over with clay) and heat
it you will find a gas coming out of the end of the tube that will burn
with a yellow smoky flame. After all the gas comes off you will find in
the bottom of the test tube a chunk of dry, porous coke. These, then,
are the two main products of the destructive distillation of coal. But
if you are an unusually observant person, that is, if you are a born
chemist with an eye to by-products, you will notice along in the middle
of the tube where it is neither too hot nor too cold some dirty drops of
water and some black sticky stuff. If you are just an ordinary person,
you won't pay any attention to this because there is only a little of it
and because what you are after is the coke and gas. You regard the
nasty, smelly mess that comes in between as merely a nuisance because it
clogs up and spoils your nice, clean tube.
Now that is the way the gas-makers and coke-makers--being for the most
part ordinary persons and not born chemists--used to regard the water
and tar that got into their pipes. They washed it out so as to have the
gas clean and then ran it into the creek. But the neighbors--especially
those who fished in the stream below the gas-works--made a fuss about
spoiling the water, so the gas-men gave away the tar to the boys for use
in celebrating the Fourth of July and election night or sold it for
roofing.
[Illustration: THE PRODUCTION OF COAL TAR
A battery of Koppers by-product coke-ovens at the plant of the Bethlehem
Steel Company, Sparrows Point, Maryland. The coke is being pushed out of
one of the ovens into the waiting car. The vapors given off from the
coal contain ammonia and the benzene compound used to make dyes and
explosives]
[Illustration: IN THESE MIXING VATS AT THE BUFFALO WORKS, ANILINE DYES
ARE PREPARED]
But this same tar, which for a hundred years was thrown away and nearly
half of which is thrown away yet in the United States, turns out to be
one of the most useful things in the world. It is one of the strategic
points in war and commerce. It wounds and heals. It supplies munitions
and medicines. It is like the magic purse of Fortunatus from which
anything wished for could be drawn. The chemist puts his hand into the
black mass and draws out all the colors of the rainbow. This
evil-smelling substance beats the rose in the production of perfume and
surpasses the honey-comb in sweetness.
Bishop Berkeley, after having proved that all matter was in your mind,
wrote a book to prove that wood tar would cure all diseases. Nobody
reads it now. The name is enough to frighten them off: "Siris: A Chain
of Philosophical Reflections and Inquiries Concerning the Virtues of Tar
Water." He had a sort of mystical idea that tar contained the
quintessence of the forest, the purified spirit of the trees, which
could somehow revive the spirit of man. People said he was crazy on the
subject, and doubtless he was, but the interesting thing about it is
that not even his active and ingenious imagination could begin to
suggest all of the strange things that can be got out of tar, whether
wood or coal.
The reason why tar supplies all sorts of useful material is because it
is indeed the quintessence of the forest, of the forests of untold
millenniums if it is coal tar. If you are acquainted with a village
tinker, one of those all-round mechanics who still survive in this age
of specialization and can mend anything from a baby-carriage to an
automobile, you will know that he has on the floor of his back shop a
heap of broken machinery from which he can get almost anything he wants,
a copper wire, a zinc plate, a brass screw or a steel rod. Now coal tar
is the scrap-heap of the vegetable kingdom. It contains a little of
almost everything that makes up trees. But you must not imagine that all
that comes out of coal tar is contained in it. There are only about a
dozen primary products extracted from coal tar, but from these the
chemist is able to build up hundreds of thousands of new substances.
This is true creative chemistry, for most of these compounds are not to
be found in plants and never existed before they were made in the
laboratory. It used to be thought that organic compounds, the products
of vegetable and animal life, could only be produced by organized
beings, that they were created out of inorganic matter by the magic
touch of some "vital principle." But since the chemist has learned how,
he finds it easier to make organic than inorganic substances and he is
confident that he can reproduce any compound that he can analyze. He
cannot only imitate the manufacturing processes of the plants and
animals, but he can often beat them at their own game.
When coal is heated in the open air it is burned up and nothing but the
ashes is left. But heat the coal in an enclosed vessel, say a big
fireclay retort, and it cannot burn up because the oxygen of the air
cannot get to it. So it breaks up. All parts of it that can be volatized
at a high heat pass off through the outlet pipe and nothing is left in
the retort but coke, that is carbon with the ash it contains. When the
escaping vapors reach a cool part of the outlet pipe the oily and tarry
matter condenses out. Then the gas is passed up through a tower down
which water spray is falling and thus is washed free from ammonia and
everything else that is soluble in water.
This process is called "destructive distillation." What products come
off depends not only upon the composition of the particular variety of
coal used, but upon the heat, pressure and rapidity of distillation. The
way you run it depends upon what you are most anxious to have. If you
want illuminating gas you will leave in it the benzene. If you are after
the greatest yield of tar products, you impoverish the gas by taking out
the benzene and get a blue instead of a bright yellow flame. If all you
are after is cheap coke, you do not bother about the by-products, but
let them escape and burn as they please. The tourist passing across the
coal region at night could see through his car window the flames of
hundreds of old-fashioned bee-hive coke-ovens and if he were of
economical mind he might reflect that this display of fireworks was
costing the country $75,000,000 a year besides consuming the
irreplaceable fuel supply of the future. But since the gas was not
needed outside of the cities and since the coal tar, if it could be sold
at all, brought only a cent or two a gallon, how could the coke-makers
be expected to throw out their old bee-hive ovens and put in the
expensive retorts and towers necessary to the recovery of the
by-products? But within the last ten years the by-product ovens have
come into use and now nearly half our coke is made in them.
Although the products of destructive distillation vary within wide
limits, yet the following table may serve to give an approximate idea of
what may be got from a ton of soft coal:
1 ton of coal may give
Gas, 12,000 cubic feet
Liquor (Washings) ammonium sulfate (7-25 pounds)
Tar (120 pounds) benzene (10-20 pounds)
toluene (3 pounds)
xylene (1-1/2 pounds)
phenol (1/2 pound)
naphthalene (3/8 pound)
anthracene (1/4 pound)
pitch (80 pounds)
Coke (1200-1500 pounds)
When the tar is redistilled we get, among other things, the ten "crudes"
which are fundamental material for making dyes. Their names are:
benzene, toluene, xylene, phenol, cresol, naphthalene, anthracene,
methyl anthracene, phenanthrene and carbazol.
There! I had to introduce you to the whole receiving line, but now that
that ceremony is over we are at liberty to do as we do at a reception,
meet our old friends, get acquainted with one or two more and turn our
backs on the rest. Two of them, I am sure, you've met before, phenol,
which is common carbolic acid, and naphthalene, which we use for
mothballs. But notice one thing in passing, that not one of them is a
dye. They are all colorless liquids or white solids. Also they all have
an indescribable odor--all odors that you don't know are
indescribable--which gives them and their progeny, even when odorless,
the name of "aromatic compounds."
[Illustration: Fig. 8. Diagram of the products obtained from coal and
some of their uses.]
The most important of the ten because he is the father of the family is
benzene, otherwise called benzol, but must not be confused with
"benzine" spelled with an _i_ which we used to burn and clean our
clothes with. "Benzine" is a kind of gasoline, but benzene _alias_
benzol has quite another constitution, although it looks and burns the
same. Now the search for the constitution of benzene is one of the most
exciting chapters in chemistry; also one of the most intricate chapters,
but, in spite of that, I believe I can make the main point of it clear
even to those who have never studied chemistry--provided they retain
their childish liking for puzzles. It is really much like putting
together the old six-block Chinese puzzle. The chemist can work better
if he has a picture of what he is working with. Now his unit is the
molecule, which is too small even to analyze with the microscope, no
matter how high powered. So he makes up a sort of diagram of the
molecule, and since he knows the number of atoms and that they are
somehow attached to one another, he represents each atom by the first
letter of its name and the points of attachment or bonds by straight
lines connecting the atoms of the different elements. Now it is one of
the rules of the game that all the bonds must be connected or hooked up
with atoms at both ends, that there shall be no free hands reaching out
into empty space. Carbon, for instance, has four bonds and hydrogen only
one. They unite, therefore, in the proportion of one atom of carbon to
four of hydrogen, or CH_{4}, which is methane or marsh gas and obviously
the simplest of the hydrocarbons. But we have more complex hydrocarbons
such as C_{6}H_{14}, known as hexane. Now if you try to draw the
diagrams or structural formulas of these two compounds you will easily
get
H H H H H H H
| | | | | | |
H-C-H H-C-C-C-C-C-C-H
| | | | | | |
H H H H H H H
methane hexane
Each carbon atom, you see, has its four hands outstretched and duly
grasped by one-handed hydrogen atoms or by neighboring carbon atoms in
the chain. We can have such chains as long as you please, thirty or more
in a chain; they are all contained in kerosene and paraffin.
So far the chemist found it east to construct diagrams that would
satisfy his sense of the fitness of things, but when he found that
benzene had the compostion C_{6}H_{6} he was puzzled. If you try to draw
the picture of C_{6}H_{6} you will get something like this:
| | | | | |
-C-C-C-C-C-C-
| | | | | |
H H H H H H
which is an absurdity because more than half of the carbon hands are
waving wildly around asking to be held by something. Benzene,
C_{6}H_{6}, evidently is like hexane, C_{6}H_{14}, in having a chain of
six carbon atoms, but it has dropped its H's like an Englishman. Eight
of the H's are missing.
Now one of the men who was worried over this benzene puzzle was the
German chemist, Kekulé. One evening after working over the problem all
day he was sitting by the fire trying to rest, but he could not throw
it off his mind. The carbon and the hydrogen atoms danced like imps on
the carpet and as he watched them through his half-closed eyes he
suddenly saw that the chain of six carbon atoms had joined at the ends
and formed a ring while the six hydrogen atoms were holding on to the
outside hands, in this fashion:
H
|
C
/ \\
H-C C-H
|| |
H-C C-H
\ //
C
|
H
Professor Kekulé saw at once that the demons of his subconscious self
had furnished him with a clue to the labyrinth, and so it proved. We
need not suppose that the benzene molecule if we could see it would look
anything like this diagram of it, but the theory works and that is all
the scientist asks of any theory. By its use thousands of new compounds
have been constructed which have proved of inestimable value to man. The
modern chemist is not a discoverer, he is an inventor. He sits down at
his desk and draws a "Kekulé ring" or rather hexagon. Then he rubs out
an H and hooks a nitro group (NO_{2}) on to the carbon in place of it;
next he rubs out the O_{2} of the nitro group and puts in H_{2}; then he
hitches on such other elements, or carbon chains and rings as he likes.
He works like an architect designing a house and when he gets a picture
of the proposed compounds to suit him he goes into the laboratory to
make it. First he takes down the bottle of benzene and boils up some of
this with nitric acid and sulfuric acid. This he puts in the nitro group
and makes nitro-benzene, C_{6}H_{5}NO_{2}. He treats this with hydrogen,
which displaces the oxygen and gives C_{6}H_{5}NH_{2} or aniline, which
is the basis of so many of these compounds that they are all commonly
called "the aniline dyes." But aniline itself is not a dye. It is a
colorless or brownish oil.
It is not necessary to follow our chemist any farther now that we have
seen how he works, but before we pass on we will just look at one of his
products, not one of the most complicated but still complicated enough.
[Illustration: A molecule of a coal-tar dye]
The name of this is sodium ditolyl-disazo-beta-naphthylamine-
6-sulfonic-beta-naphthylamine-3.6-disulfonate.
These chemical names of organic compounds are discouraging to the
beginner and amusing to the layman, but that is because neither of them
realizes that they are not really words but formulas. They are
hyphenated because they come from Germany. The name given above is no
more of a mouthful than "a-square-plus-two-a-b-plus-b-square" or "Third
Assistant Secretary of War to the President of the United States of
America." The trade name of this dye is Brilliant Congo, but while that
is handier to say it does not mean anything. Nobody but an expert in
dyes would know what it was, while from the formula name any chemist
familiar with such compounds could draw its picture, tell how it would
behave and what it was made from, or even make it. The old alchemist was
a secretive and pretentious person and used to invent queer names for
the purpose of mystifying and awing the ignorant. But the chemist in
dropping the al- has dropped the idea of secrecy and his names, though
equally appalling to the layman, are designed to reveal and not to
conceal.
From this brief explanation the reader who has not studied chemistry
will, I think, be able to get some idea of how these very intricate
compounds are built up step by step. A completed house is hard to
understand, but when we see the mason laying one brick on top of another
it does not seem so difficult, although if we tried to do it we should
not find it so easy as we think. Anyhow, let me give you a hint. If you
want to make a good impression on a chemist don't tell him that he
seems to you a sort of magician, master of a black art, and all that
nonsense. The chemist has been trying for three hundred years to live
down the reputation of being inspired of the devil and it makes him mad
to have his past thrown up at him in this fashion. If his tactless
admirers would stop saying "it is all a mystery and a miracle to me,
and I cannot understand it" and pay attention to what he is telling them
they would understand it and would find that it is no more of a mystery
or a miracle than anything else. You can make an electrician mad in the
same way by interrupting his explanation of a dynamo by asking: "But you
cannot tell me what electricity really is." The electrician does not
care a rap what electricity "really is"--if there really is any meaning
to that phrase. All he wants to know is what he can do with it.
[Illustration: COMPARISON OF COAL AND ITS DISTILLATION PRODUCTS From
Hesse's "The Industry of the Coal Tar Dyes," _Journal of Industrial and
Engineering Chemistry_, December, 1914]
The tar obtained from the gas plant or the coke plant has now to be
redistilled, giving off the ten "crudes" already mentioned and leaving
in the still sixty-five per cent. of pitch, which may be used for
roofing, paving and the like. The ten primary products or crudes are
then converted into secondary products or "intermediates" by processes
like that for the conversion of benzene into aniline. There are some
three hundred of these intermediates in use and from them are built up
more than three times as many dyes. The year before the war the American
custom house listed 5674 distinct brands of synthetic dyes imported,
chiefly from Germany, but some of these were trade names for the same
product made by different firms or represented by different degrees of
purity or form of preparation. Although the number of possible products
is unlimited and over five thousand dyes are known, yet only about nine
hundred are in use. We can summarize the situation so:
Coal-tar --> 10 crudes --> 300 intermediates --> 900 dyes --> 5000 brands.
Or, to borrow the neat simile used by Dr. Bernhard C. Hesse, it is like
cloth-making where "ten fibers make 300 yarns which are woven into 900
patterns."
The advantage of the artificial dyestuffs over those found in nature
lies in their variety and adaptability. Practically any desired tint or
shade can be made for any particular fabric. If my lady wants a new kind
of green for her stockings or her hair she can have it. Candies and
jellies and drinks can be made more attractive and therefore more
appetizing by varied colors. Easter eggs and Easter bonnets take on new
and brighter hues.
More and more the chemist is becoming the architect of his own fortunes.
He does not make discoveries by picking up a beaker and pouring into it
a little from each bottle on the shelf to see what happens. He generally
knows what he is after, and he generally gets it, although he is still
often baffled and occasionally happens on something quite unexpected and
perhaps more valuable than what he was looking for. Columbus was looking
for India when he ran into an obstacle that proved to be America.
William Henry Perkin was looking for quinine when he blundered into that
rich and undiscovered country, the aniline dyes. William Henry was a
queer boy. He had rather listen to a chemistry lecture than eat. When he
was attending the City of London School at the age of thirteen there was
an extra course of lectures on chemistry given at the noon recess, so he
skipped his lunch to take them in. Hearing that a German chemist named
Hofmann had opened a laboratory in the Royal College of London he headed
for that. Hofmann obviously had no fear of forcing the young intellect
prematurely. He perhaps had never heard that "the tender petals of the
adolescent mind must be allowed to open slowly." He admitted young
Perkin at the age of fifteen and started him on research at the end of
his second year. An American student nowadays thinks he is lucky if he
gets started on his research five years older than Perkin. Now if
Hofmann had studied pedagogical psychology he would have been informed
that nothing chills the ardor of the adolescent mind like being set at
tasks too great for its powers. If he had heard this and believed it, he
would not have allowed Perkin to spend two years in fruitless endeavors
to isolate phenanthrene from coal tar and to prepare artificial
quinine--and in that case Perkin would never have discovered the aniline
dyes. But Perkin, so far from being discouraged, set up a private
laboratory so he could work over-time. While working here during the
Easter vacation of 1856--the date is as well worth remembering as
1066--he was oxidizing some aniline oil when he got what chemists most
detest, a black, tarry mass instead of nice, clean crystals. When he
went to wash this out with alcohol he was surprised to find that it gave
a beautiful purple solution. This was "mauve," the first of the aniline
dyes.
The funny thing about it was that when Perkin tried to repeat the
experiment with purer aniline he could not get his color. It was because
he was working with impure chemicals, with aniline containing a little
toluidine, that he discovered mauve. It was, as I said, a lucky
accident. But it was not accidental that the accident happened to the
young fellow who spent his noonings and vacations at the study of
chemistry. A man may not find what he is looking for, but he never
finds anything unless he is looking for something.
Mauve was a product of creative chemistry, for it was a substance that
had never existed before. Perkin's next great triumph, ten years later,
was in rivaling Nature in the manufacture of one of her own choice
products. This is alizarin, the coloring matter contained in the madder
root. It was an ancient and oriental dyestuff, known as "Turkey red" or
by its Arabic name of "alizari." When madder was introduced into France
it became a profitable crop and at one time half a million tons a year
were raised. A couple of French chemists, Robiquet and Colin, extracted
from madder its active principle, alizarin, in 1828, but it was not
until forty years later that it was discovered that alizarin had for its
base one of the coal-tar products, anthracene. Then came a neck-and-neck
race between Perkin and his German rivals to see which could discover a
cheap process for making alizarin from anthracene. The German chemists
beat him to the patent office by one day! Graebe and Liebermann filed
their application for a patent on the sulfuric acid process as No. 1936
on June 25, 1869. Perkin filed his for the same process as No. 1948 on
June 26. It had required twenty years to determine the constitution of
alizarin, but within six months from its first synthesis the commercial
process was developed and within a few years the sale of artificial
alizarin reached $8,000,000 annually. The madder fields of France were
put to other uses and even the French soldiers became dependent on
made-in-Germany dyes for their red trousers. The British soldiers were
placed in a similar situation as regards their red coats when after
1878 the azo scarlets put the cochineal bug out of business.
The modern chemist has robbed royalty of its most distinctive insignia,
Tyrian purple. In ancient times to be "porphyrogene," that is "born to
the purple," was like admission to the Almanach de Gotha at the present
time, for only princes or their wealthy rivals could afford to pay $600
a pound for crimsoned linen. The precious dye is secreted by a
snail-like shellfish of the eastern coast of the Mediterranean. From a
tiny sac behind the head a drop of thick whitish liquid, smelling like
garlic, can be extracted. If this is spread upon cloth of any kind and
exposed to air and sunlight it turns first green, next blue and then
purple. If the cloth is washed with soap--that is, set by alkali--it
becomes a fast crimson, such as Catholic cardinals still wear as princes
of the church. The Phoenician merchants made fortunes out of their
monopoly, but after the fall of Tyre it became one of "the lost
arts"--and accordingly considered by those whose faces are set toward
the past as much more wonderful than any of the new arts. But in 1909
Friedlander put an end to the superstition by analyzing Tyrian purple
and finding that it was already known. It was the same as a dye that had
been prepared five years before by Sachs but had not come into
commercial use because of its inferiority to others in the market. It
required 12,000 of the mollusks to supply the little material needed for
analysis, but once the chemist had identified it he did not need to
bother the Murex further, for he could make it by the ton if he had
wanted to. The coloring principle turned out to be a di-brom indigo,
that is the same as the substance extracted from the Indian plant, but
with the addition of two atoms of bromine. Why a particular kind of a
shellfish should have got the habit of extracting this rare element from
sea water and stowing it away in this peculiar form is "one of those
things no fellow can find out." But according to the chemist the Murex
mollusk made a mistake in hitching the bromine to the wrong carbon
atoms. He finds as he would word it that the 6:6' di-brom indigo
secreted by the shellfish is not so good as the 5:5' di-brom indigo now
manufactured at a cheap rate and in unlimited quantity. But we must not
expect too much of a mollusk's mind. In their cheapness lies the offense
of the aniline dyes in the minds of some people. Our modern aristocrats
would delight to be entitled "porphyrogeniti" and to wear exclusive
gowns of "purple and scarlet from the isles of Elishah" as was done in
Ezekiel's time, but when any shopgirl or sailor can wear the royal color
it spoils its beauty in their eyes. Applied science accomplishes a real
democracy such as legislation has ever failed to establish.
Any kind of dye found in nature can be made in the laboratory whenever
its composition is understood and usually it can be made cheaper and
purer than it can be extracted from the plant. But to work out a
profitable process for making it synthetically is sometimes a task
requiring high skill, persistent labor and heavy expenditure. One of the
latest and most striking of these achievements of synthetic chemistry is
the manufacture of indigo.
Indigo is one of the oldest and fastest of the dyestuffs. To see that it
is both ancient and lasting look at the unfaded blue cloths that enwrap
an Egyptian mummy. When Caesar conquered our British ancestors he found
them tattooed with woad, the native indigo. But the chief source of
indigo was, as its name implies, India. In 1897 nearly a million acres
in India were growing the indigo plant and the annual value of the crop
was $20,000,000. Then the fall began and by 1914 India was producing
only $300,000 worth! What had happened to destroy this profitable
industry? Some blight or insect? No, it was simply that the Badische
Anilin-und-Soda Fabrik had worked out a practical process for making
artificial indigo.
That indigo on breaking up gave off aniline was discovered as early as
1840. In fact that was how aniline got its name, for when Fritzsche
distilled indigo with caustic soda he called the colorless distillate
"aniline," from the Arabic name for indigo, "anil" or "al-nil," that is,
"the blue-stuff." But how to reverse the process and get indigo from
aniline puzzled chemists for more than forty years until finally it was
solved by Adolf von Baeyer of Munich, who died in 1917 at the age of
eighty-four. He worked on the problem of the constitution of indigo for
fifteen years and discovered several ways of making it. It is possible
to start from benzene, toluene or naphthalene. The first process was the
easiest, but if you will refer to the products of the distillation of
tar you will find that the amount of toluene produced is less than the
naphthalene, which is hard to dispose of. That is, if a dye factory had
worked out a process for making indigo from toluene it would not be
practicable because there was not enough toluene produced to supply the
demand for indigo. So the more complicated napthalene process was
chosen in preference to the others in order to utilize this by-product.
The Badische Anilin-und-Soda Fabrik spent $5,000,000 and seventeen years
in chemical research before they could make indigo, but they gained a
monopoly (or, to be exact, ninety-six per cent.) of the world's
production. A hundred years ago indigo cost as much as $4 a pound. In
1914 we were paying fifteen cents a pound for it. Even the pauper labor
of India could not compete with the German chemists at that price. At
the beginning of the present century Germany was paying more than
$3,000,000 a year for indigo. Fourteen years later Germany was _selling_
indigo to the amount of $12,600,000. Besides its cheapness, artificial
indigo is preferable because it is of uniform quality and greater
purity. Vegetable indigo contains from forty to eighty per cent. of
impurities, among them various other tinctorial substances. Artificial
indigo is made pure and of any desired strength, so the dyers can depend
on it.
The value of the aniline colors lies in their infinite variety. Some are
fast, some will fade, some will stand wear and weather as long as the
fabric, some will wash out on the spot. Dyes can be made that will
attach themselves to wool, to silk or to cotton, and give it any shade
of any color. The period of discovery by accident has long gone by. The
chemist nowadays decides first just what kind of a dye he wants, and
then goes to work systematically to make it. He begins by drawing a
diagram of the molecule, double-linking nitrogen or carbon and oxygen
atoms to give the required intensity, putting in acid or basic radicals
to fasten it to the fiber, shifting the color back and forth along the
spectrum at will by introducing methyl groups, until he gets it just to
his liking.
Art can go ahead of nature in the dyestuff business. Before man found
that he could make all the dyes he wanted from the tar he had been
burning up at home he searched the wide world over to find colors by
which he could make himself--or his wife--garments as beautiful as those
that arrayed the flower, the bird and the butterfly. He sent divers down
into the Mediterranean to rob the murex of his purple. He sent ships to
the new world to get Brazil wood and to the oldest world for indigo. He
robbed the lady cochineal of her scarlet coat. Why these peculiar
substances were formed only by these particular plants, mussels and
insects it is hard to understand. I don't know that Mrs. Cacti Coccus
derived any benefit from her scarlet uniform when khaki would be safer,
and I can't imagine that to a shellfish it was of advantage to turn red
as it rots or to an indigo plant that its leaves in decomposing should
turn blue. But anyhow, it was man that took advantage of them until he
learned how to make his own dyestuffs.
Our independent ancestors got along so far as possible with what grew in
the neighborhood. Sweetapple bark gave a fine saffron yellow. Ribbons
were given the hue of the rose by poke berry juice. The Confederates in
their butternut-colored uniform were almost as invisible as if in khaki
or _feldgrau_. Madder was cultivated in the kitchen garden. Only logwood
from Jamaica and indigo from India had to be imported. That we are not
so independent today is our own fault, for we waste enough coal tar to
supply ourselves and other countries with all the new dyes needed. It is
essentially a question of economy and organization. We have forgotten
how to economize, but we have learned how to organize.
The British Government gave the discoverer of mauve a title, but it did
not give him any support in his endeavors to develop the industry,
although England led the world in textiles and needed more dyes than any
other country. So in 1874 Sir William Perkin relinquished the attempt to
manufacture the dyes he had discovered because, as he said, Oxford and
Cambridge refused to educate chemists or to carry on research. Their
students, trained in the classics for the profession of being a
gentleman, showed a decided repugnance to the laboratory on account of
its bad smells. So when Hofmann went home he virtually took the infant
industry along with him to Germany, where Ph.D.'s were cheap and
plentiful and not afraid of bad smells. There the business throve
amazingly, and by 1914 the Germans were manufacturing more than
three-fourths of all the coal-tar products of the world and supplying
material for most of the rest. The British cursed the universities for
thus imperiling the nation through their narrowness and neglect; but
this accusation, though natural, was not altogether fair, for at least
half the blame should go to the British dyer, who did not care where his
colors came from, so long as they were cheap. When finally the
universities did turn over a new leaf and began to educate chemists, the
manufacturers would not employ them. Before the war six English
factories producing dyestuffs employed only 35 chemists altogether,
while one German color works, the Höchster Farbwerke, employed 307
expert chemists and 74 technologists.
This firm united with the six other leading dye companies of Germany on
January 1, 1916, to form a trust to last for fifty years. During this
time they will maintain uniform prices and uniform wage scales and hours
of labor, and exchange patents and secrets. They will divide the foreign
business _pro rata_ and share the profits. The German chemical works
made big profits during the war, mostly from munitions and medicines,
and will be, through this new combination, in a stronger position than
ever to push the export trade.
As a consequence of letting the dye business get away from her, England
found herself in a fix when war broke out. She did not have dyes for her
uniforms and flags, and she did not have drugs for her wounded. She
could not take advantage of the blockade to capture the German trade in
Asia and South America, because she could not color her textiles. A blue
cotton dyestuff that sold before the war at sixty cents a pound, brought
$34 a pound. A bright pink rhodamine formerly quoted at a dollar a pound
jumped to $48. When one keg of dye ordinarily worth $15 was put up at
forced auction sale in 1915 it was knocked down at $1500. The
Highlanders could not get the colors for their kilts until some German
dyes were smuggled into England. The textile industries of Great
Britain, that brought in a billion dollars a year and employed one and a
half million workers, were crippled for lack of dyes. The demand for
high explosives from the front could not be met because these also are
largely coal-tar products. Picric acid is both a dye and an explosive.
It is made from carbolic acid and the famous trinitrotoluene is made
from toluene, both of which you will find in the list of the ten
fundamental "crudes."
Both Great Britain and the United States realized the danger of allowing
Germany to recover her former monopoly, and both have shown a readiness
to cast overboard their traditional policies to meet this emergency. The
British Government has discovered that a country without a tariff is a
land without walls. The American Government has discovered that an
industry is not benefited by being cut up into small pieces. Both
governments are now doing all they can to build up big concerns and to
provide them with protection. The British Government assisted in the
formation of a national company for the manufacture of synthetic dyes by
taking one-sixth of the stock and providing $500,000 for a research
laboratory. But this effort is now reported to be "a great failure"
because the Government put it in charge of the politicians instead of
the chemists.
The United States, like England, had become dependent upon Germany for
its dyestuffs. We imported nine-tenths of what we used and most of those
that were produced here were made from imported intermediates. When the
war broke out there were only seven firms and 528 persons employed in
the manufacture of dyes in the United States. One of these, the
Schoelkopf Aniline and Chemical Works, of Buffalo, deserves mention, for
it had stuck it out ever since 1879, and in 1914 was making 106 dyes. In
June, 1917, this firm, with the encouragement of the Government Bureau
of Foreign and Domestic Commerce, joined with some of the other American
producers to form a trade combination, the National Aniline and Chemical
Company. The Du Pont Company also entered the field on an extensive
scale and soon there were 118 concerns engaged in it with great profit.
During the war $200,000,000 was invested in the domestic dyestuff
industry. To protect this industry Congress put on a specific duty of
five cents a pound and an ad valorem duty of 30 per cent. on imported
dyestuffs; but if, after five years, American manufacturers are not
producing 60 per cent. in value of the domestic consumption, the
protection is to be removed. For some reason, not clearly understood and
therefore hotly discussed, Congress at the last moment struck off the
specific duty from two of the most important of the dyestuffs, indigo
and alizarin, as well as from all medicinals and flavors.
The manufacture of dyes is not a big business, but it is a strategic
business. Heligoland is not a big island, but England would have been
glad to buy it back during the war at a high price per square yard.
American industries employing over two million men and women and
producing over three billion dollars' worth of products a year are
dependent upon dyes. Chief of these is of course textiles, using more
than half the dyes; next come leather, paper, paint and ink. We have
been importing more than $12,000,000 worth of coal-tar products a year,
but the cottonseed oil we exported in 1912 would alone suffice to pay
that bill twice over. But although the manufacture of dyes cannot be
called a big business, in comparison with some others, it is a paying
business when well managed. The German concerns paid on an average 22
per cent. dividends on their capital and sometimes as high as 50 per
cent. Most of the standard dyes have been so long in use that the
patents are off and the processes are well enough known. We have the
coal tar and we have the chemists, so there seems no good reason why we
should not make our own dyes, at least enough of them so we will not be
caught napping as we were in 1914. It was decidedly humiliating for our
Government to have to beg Germany to sell us enough colors to print our
stamps and greenbacks and then have to beg Great Britain for permission
to bring them over by Dutch ships.
The raw material for the production of coal-tar products we have in
abundance if we will only take the trouble to save it. In 1914 the crude
light oil collected from the coke-ovens would have produced only about
4,500,000 gallons of benzol and 1,500,000 gallons of toluol, but in 1917
this output was raised to 40,200,000 gallons of benzol and 10,200,000 of
toluol. The toluol was used mostly in the manufacture of trinitrotoluol
for use in Europe. When the war broke out in 1914 it shut off our supply
of phenol (carbolic acid) for which we were dependent upon foreign
sources. This threatened not only to afflict us with headaches by
depriving us of aspirin but also to removed the consolation of music,
for phenol is used in making phonographic records. Mr. Edison with his
accustomed energy put up a factory within a few weeks for the
manufacture of synthetic phenol. When we entered the war the need for
phenol became yet more imperative, for it was needed to make picric
acid for filling bombs. This demand was met, and in 1917 there were
fifteen new plants turning out 64,146,499 pounds of phenol valued at
$23,719,805.
Some of the coal-tar products, as we see, serve many purposes. For
instance, picric acid appears in three places in this book. It is a high
explosive. It is a powerful and permanent yellow dye as any one who has
touched it knows. Thirdly it is used as an antiseptic to cover burned
skin. Other coal-tar dyes are used for the same purpose, "malachite
green," "brilliant green," "crystal violet," "ethyl violet" and
"Victoria blue," so a patient in a military hospital is decorated like
an Easter egg. During the last five years surgeons have unfortunately
had unprecedented opportunities for the study of wounds and fortunately
they have been unprecedentedly successful in finding improved methods of
treating them. In former wars a serious wound meant usually death or
amputation. Now nearly ninety per cent. of the wounded are able to
continue in the service. The reason for this improvement is that
medicines are now being made to order instead of being gathered "from
China to Peru." The old herb doctor picked up any strange plant that he
could find and tried it on any sick man that would let him. This
empirical method, though hard on the patients, resulted in the course of
five thousand years in the discovery of a number of useful remedies. But
the modern medicine man when he knows the cause of the disease is
usually able to devise ways of counteracting it directly. For instance,
he knows, thanks to Pasteur and Metchnikoff, that the cause of wound
infection is the bacterial enemies of man which swarm by the million
into any breach in his protective armor, the skin. Now when a breach is
made in a line of intrenchments the defenders rush troops to the
threatened spot for two purposes, constructive and destructive,
engineers and warriors, the former to build up the rampart with
sandbags, the latter to kill the enemy. So when the human body is
invaded the blood brings to the breach two kinds of defenders. One is
the serum which neutralizes the bacterial poison and by coagulating
forms a new skin or scab over the exposed flesh. The other is the
phagocytes or white corpuscles, the free lances of our corporeal
militia, which attack and kill the invading bacteria. The aim of the
physician then is to aid these defenders as much as possible without
interfering with them. Therefore the antiseptic he is seeking is one
that will assist the serum in protecting and repairing the broken
tissues and will kill the hostile bacteria without killing the friendly
phagocytes. Carbolic acid, the most familiar of the coal-tar
antiseptics, will destroy the bacteria when it is diluted with 250 parts
of water, but unfortunately it puts a stop to the fighting activities of
the phagocytes when it is only half that strength, or one to 500, so it
cannot destroy the infection without hindering the healing.
In this search for substances that would attack a specific disease germ
one of the leading investigators was Prof. Paul Ehrlich, a German
physician of the Hebrew race. He found that the aniline dyes were useful
for staining slides under the microscope, for they would pick out
particular cells and leave others uncolored and from this starting point
he worked out organic and metallic compounds which would destroy the
bacteria and parasites that cause some of the most dreadful of diseases.
A year after the war broke out Professor Ehrlich died while working in
his laboratory on how to heal with coal-tar compounds the wounds
inflicted by explosives from the same source.
One of the most valuable of the aniline antiseptics employed by Ehrlich
is flavine or, if the reader prefers to call it by its full name,
diaminomethylacridinium chloride. Flavine, as its name implies, is a
yellow dye and will kill the germs causing ordinary abscesses when in
solution as dilute as one part of the dye to 200,000 parts of water, but
it does not interfere with the bactericidal action of the white blood
corpuscles unless the solution is 400 times as strong as this, that is
one part in 500. Unlike carbolic acid and other antiseptics it is said
to stimulate the serum instead of impairing its activity. Another
antiseptic of the coal-tar family which has recently been brought into
use by Dr. Dakin of the Rockefeller Institute is that called by European
physicians chloramine-T and by American physicians chlorazene and by
chemists para-toluene-sodium-sulfo-chloramide.
This may serve to illustrate how a chemist is able to make such remedies
as the doctor needs, instead of depending upon the accidental
by-products of plants. On an earlier page I explained how by starting
with the simplest of ring-compounds, the benzene of coal tar, we could
get aniline. Suppose we go a step further and boil the aniline oil with
acetic acid, which is the acid of vinegar minus its water. This easy
process gives us acetanilid, which when introduced into the market some
years ago under the name of "antifebrin" made a fortune for its makers.
The making of medicines from coal tar began in 1874 when Kolbe made
salicylic acid from carbolic acid. Salicylic acid is a rheumatism remedy
and had previously been extracted from willow bark. If now we treat
salicylic acid with concentrated acetic acid we get "aspirin." From
aniline again are made "phenacetin," "antipyrin" and a lot of other
drugs that have become altogether too popular as headache remedies--say
rather "headache relievers."
Another class of synthetics equally useful and likewise abused, are the
soporifics, such as "sulphonal," "veronal" and "medinal." When it is not
desired to put the patient to sleep but merely to render insensible a
particular place, as when a tooth is to be pulled, cocain may be used.
This, like alcohol and morphine, has proved a curse as well as a
blessing and its sale has had to be restricted because of the many
victims to the habit of using this drug. Cocain is obtained from the
leaves of the South American coca tree, but can be made artificially
from coal-tar products. The laboratory is superior to the forest because
other forms of local anesthetics, such as eucain and novocain, can be
made that are better than the natural alkaloid because more effective
and less poisonous.
I must not forget to mention another lot of coal-tar derivatives in
which some of my readers will take a personal interest. That is the
photographic developers. I am old enough to remember when we used to
develop our plates in ferrous sulfate solution and you never saw nicer
negatives than we got with it. But when pyrogallic acid came in we
switched over to that even though it did stain our fingers and sometimes
our plates. Later came a swarm of new organic reducing agents under
various fancy names, such as metol, hydro (short for hydro-quinone) and
eikongen ("the image-maker"). Every fellow fixed up his own formula and
called his fellow-members of the camera club fools for not adopting it
though he secretly hoped they would not.
Under the double stimulus of patriotism and high prices the American
drug and dyestuff industry developed rapidly. In 1917 about as many
pounds of dyes were manufactured in America as were imported in 1913 and
our _exports_ of American-made dyes exceeded in value our _imports_
before the war. In 1914 the output of American dyes was valued at
$2,500,000. In 1917 it amounted to over $57,000,000. This does not mean
that the problem was solved, for the home products were not equal in
variety and sometimes not in quality to those made in Germany. Many
valuable dyes were lacking and the cost was of course much higher.
Whether the American industry can compete with the foreign in an open
market and on equal terms is impossible to say because such conditions
did not prevail before the war and they are not going to prevail in the
future. Formerly the large German cartels through their agents and
branches in this country kept the business in their own hands and now
the American manufacturers are determined to maintain the independence
they have acquired. They will not depend hereafter upon the tariff to
cut off competition but have adopted more effective measures. The 4500
German chemical patents that had been seized by the Alien Property
Custodian were sold by him for $250,000 to the Chemical Foundation, an
association of American manufacturers organized "for the Americanization
of such institutions as may be affected thereby, for the exclusion or
elimination of alien interests hostile or detrimental to said industries
and for the advancement of chemical and allied science and industry in
the United States." The Foundation has a large fighting fund so that it
"may be able to commence immediately and prosecute with the utmost vigor
infringement proceedings whenever the first German attempt shall
hereafter be made to import into this country."
So much mystery has been made of the achievements of German chemists--as
though the Teutonic brain had a special lobe for that faculty, lacking
in other craniums--that I want to quote what Dr. Hesse says about his
first impressions of a German laboratory of industrial research:
Directly after graduating from the University of Chicago in
1896, I entered the employ of the largest coal-tar dye works in
the world at its plant in Germany and indeed in one of its
research laboratories. This was my first trip outside the
United States and it was, of course, an event of the first
magnitude for me to be in Europe, and, as a chemist, to be in
Germany, in a German coal-tar dye plant, and to cap it all in
its research laboratory--a real _sanctum sanctorum_ for
chemists. In a short time the daily routine wore the novelty
off my experience and I then settled down to calm analysis and
dispassionate appraisal of my surroundings and to compare what
was actually before and around me with my expectations. I
found that the general laboratory equipment was no better than
what I had been accustomed to; that my colleagues had no better
fundamental training than I had enjoyed nor any better fact--or
manipulative--equipment than I; that those in charge of the
work had no better general intellectual equipment nor any more
native ability than had my instructors; in short, there was
nothing new about it all, nothing that we did not have back
home, nothing--except the specific problems that were engaging
their attention, and the special opportunities of attacking
them. Those problems were of no higher order of complexity than
those I had been accustomed to for years, in fact, most of them
were not very complex from a purely intellectual viewpoint.
There was nothing inherently uncanny, magical or wizardly about
their occupation whatever. It was nothing but plain hard work
and keeping everlastingly at it. Now, what was the actual thing
behind that chemical laboratory that we did not have at home?
It was money, willing to back such activity, convinced that in
the final outcome, a profit would be made; money, willing to
take university graduates expecting from them no special
knowledge other than a good and thorough grounding in
scientific research and provide them with opportunity to become
specialists suited to the factory's needs.
It is evidently not impossible to make the United States self-sufficient
in the matter of coal-tar products. We've got the tar; we've got the
men; we've got the money, too. Whether such a policy would pay us in the
long run or whether it is necessary as a measure of military or
commercial self-defense is another question that cannot here be decided.
But whatever share we may have in it the coal-tar industry has increased
the economy of civilization and added to the wealth of the world by
showing how a waste by-product could be utilized for making new dyes and
valuable medicines, a better use for tar than as fuel for political
bonfires and as clothing for the nakedness of social outcasts.
V
SYNTHETIC PERFUMES AND FLAVORS
The primitive man got his living out of such wild plants and animals as
he could find. Next he, or more likely his wife, began to cultivate the
plants and tame the animals so as to insure a constant supply. This was
the first step toward civilization, for when men had to settle down in a
community (_civitas_) they had to ameliorate their manners and make laws
protecting land and property. In this settled and orderly life the
plants and animals improved as well as man and returned a hundredfold
for the pains that their master had taken in their training. But still
man was dependent upon the chance bounties of nature. He could select,
but he could not invent. He could cultivate, but he could not create. If
he wanted sugar he had to send to the West Indies. If he wanted spices
he had to send to the East Indies. If he wanted indigo he had to send to
India. If he wanted a febrifuge he had to send to Peru. If he wanted a
fertilizer he had to send to Chile. If he wanted rubber he had to send
to the Congo. If he wanted rubies he had to send to Mandalay. If he
wanted otto of roses he had to send to Turkey. Man was not yet master of
his environment.
This period of cultivation, the second stage of civilization, began
before the dawn of history and lasted until recent times. We might
almost say up to the twentieth century, for it was not until the
fundamental laws of heredity were discovered that man could originate
new species of plants and animals according to a predetermined plan by
combining such characteristics as he desired to perpetuate. And it was
not until the fundamental laws of chemistry were discovered that man
could originate new compounds more suitable to his purpose than any to
be found in nature. Since the progress of mankind is continuous it is
impossible to draw a date line, unless a very jagged one, along the
frontier of human culture, but it is evident that we are just entering
upon the third era of evolution in which man will make what he needs
instead of trying to find it somewhere. The new epoch has hardly dawned,
yet already a man may stay at home in New York or London and make his
own rubber and rubies, his own indigo and otto of roses. More than this,
he can make gems and colors and perfumes that never existed since time
began. The man of science has signed a declaration of independence of
the lower world and we are now in the midst of the revolution.
Our eyes are dazzled by the dawn of the new era. We know what the hunter
and the horticulturist have already done for man, but we cannot imagine
what the chemist can do. If we look ahead through the eyes of one of the
greatest of French chemists, Berthelot, this is what we shall see:
The problem of food is a chemical problem. Whenever energy can
be obtained economically we can begin to make all kinds of
aliment, with carbon borrowed from carbonic acid, hydrogen
taken from the water and oxygen and nitrogen drawn from the
air.... The day will come when each person will carry for his
nourishment his little nitrogenous tablet, his pat of fatty
matter, his package of starch or sugar, his vial of aromatic
spices suited to his personal taste; all manufactured
economically and in unlimited quantities; all independent of
irregular seasons, drought and rain, of the heat that withers
the plant and of the frost that blights the fruit; all free
from pathogenic microbes, the origin of epidemics and the
enemies of human life. On that day chemistry will have
accomplished a world-wide revolution that cannot be estimated.
There will no longer be hills covered with vineyards and fields
filled with cattle. Man will gain in gentleness and morality
because he will cease to live by the carnage and destruction of
living creatures.... The earth will be covered with grass,
flowers and woods and in it the human race will dwell in the
abundance and joy of the legendary age of gold--provided that a
spiritual chemistry has been discovered that changes the nature
of man as profoundly as our chemistry transforms material
nature.
But this is looking so far into the future that we can trust no man's
eyesight, not even Berthelot's. There is apparently no impossibility
about the manufacture of synthetic food, but at present there is no
apparent probability of it. There is no likelihood that the laboratory
will ever rival the wheat field. The cornstalk will always be able to
work cheaper than the chemist in the manufacture of starch. But in rarer
and choicer products of nature the chemist has proved his ability to
compete and even to excel.
What have been from the dawn of history to the rise of synthetic
chemistry the most costly products of nature? What could tempt a
merchant to brave the perils of a caravan journey over the deserts of
Asia beset with Arab robbers? What induced the Portuguese and Spanish
mariners to risk their frail barks on perilous waters of the Cape of
Good Hope or the Horn? The chief prizes were perfumes, spices, drugs and
gems. And why these rather than what now constitutes the bulk of oversea
and overland commerce? Because they were precious, portable and
imperishable. If the merchant got back safe after a year or two with a
little flask of otto of roses, a package of camphor and a few pearls
concealed in his garments his fortune was made. If a single ship of the
argosy sent out from Lisbon came back with a load of sandalwood, indigo
or nutmeg it was regarded as a successful venture. You know from reading
the Bible, or if not that, from your reading of Arabian Nights, that a
few grains of frankincense or a few drops of perfumed oil were regarded
as gifts worthy the acceptance of a king or a god. These products of the
Orient were equally in demand by the toilet and the temple. The
unctorium was an adjunct of the Roman bathroom. Kings had to be greased
and fumigated before they were thought fit to sit upon a throne. There
was a theory, not yet altogether extinct, that medicines brought from a
distance were most efficacious, especially if, besides being expensive,
they tasted bad like myrrh or smelled bad like asafetida. And if these
failed to save the princely patient he was embalmed in aromatics or, as
we now call them, antiseptics of the benzene series.
Today, as always, men are willing to pay high for the titillation of the
senses of smell and taste. The African savage will trade off an ivory
tusk for a piece of soap reeking with synthetic musk. The clubman will
pay $10 for a bottle of wine which consists mostly of water with about
ten per cent. of alcohol, worth a cent or two, but contains an
unweighable amount of the "bouquet" that can only be produced on the
sunny slopes of Champagne or in the valley of the Rhine. But very likely
the reader is quite as extravagant, for when one buys the natural violet
perfumery he is paying at the rate of more than $10,000 a pound for the
odoriferous oil it contains; the rest is mere water and alcohol. But you
would not want the pure undiluted oil if you could get it, for it is
unendurable. A single whiff of it paralyzes your sense of smell for a
time just as a loud noise deafens you.
Of the five senses, three are physical and two chemical. By touch we
discern pressures and surface textures. By hearing we receive
impressions of certain air waves and by sight of certain ether waves.
But smell and taste lead us to the heart of the molecule and enable us
to tell how the atoms are put together. These twin senses stand like
sentries at the portals of the body, where they closely scrutinize
everything that enters. Sounds and sights may be disagreeable, but they
are never fatal. A man can live in a boiler factory or in a cubist art
gallery, but he cannot live in a room containing hydrogen sulfide. Since
it is more important to be warned of danger than guided to delights our
senses are made more sensitive to pain than pleasure. We can detect by
the smell one two-millionth of a milligram of oil of roses or musk, but
we can detect one two-billionth of a milligram of mercaptan, which is
the vilest smelling compound that man has so far invented. If you do not
know how much a milligram is consider a drop picked up by the point of
a needle and imagine that divided into two billion parts. Also try to
estimate the weight of the odorous particles that guide a dog to the fox
or warn a deer of the presence of man. The unaided nostril can rival the
spectroscope in the detection and analysis of unweighable amounts of
matter.
What we call flavor or savor is a joint effect of taste and odor in
which the latter predominates. There are only four tastes of importance,
acid, alkaline, bitter and sweet. The acid, or sour taste, is the
perception of hydrogen atoms charged with positive electricity. The
alkaline, or soapy taste, is the perception of hydroxyl radicles charged
with negative electricity. The bitter and sweet tastes and all the odors
depend upon the chemical constitution of the compound, but the laws of
the relation have not yet been worked out. Since these sense organs, the
taste and smell buds, are sunk in the moist mucous membrane they can
only be touched by substances soluble in water, and to reach the sense
of smell they must also be volatile so as to be diffused in the air
inhaled by the nose. The "taste" of food is mostly due to the volatile
odors of it that creep up the back-stairs into the olfactory chamber.
A chemist given an unknown substance would have to make an elementary
analysis and some tedious tests to determine whether it contained methyl
or ethyl groups, whether it was an aldehyde or an ester, whether the
carbon atoms were singly or doubly linked and whether it was an open
chain or closed. But let him get a whiff of it and he can give instantly
a pretty shrewd guess as to these points. His nose knows.
Although the chemist does not yet know enough to tell for certain from
looking at the structural formula what sort of odor the compound would
have or whether it would have any, yet we can divide odoriferous
substances into classes according to their constitution. What are
commonly known as "fruity" odors belong mostly to what the chemist calls
the fatty or aliphatic series. For instance, we may have in a ripe fruit
an alcohol (say ethyl or common alcohol) and an acid (say acetic or
vinegar) and a combination of these, the ester or organic salt (in this
case ethyl acetate), which is more odorous than either of its
components. These esters of the fatty acids give the characteristic
savor to many of our favorite fruits, candies and beverages. The pear
flavor, amyl acetate, is made from acetic acid and amyl alcohol--though
amyl alcohol (fusel oil) has a detestable smell. Pineapple is ethyl
butyrate--but the acid part of it (butyric acid) is what gives Limburger
cheese its aroma. These essential oils are easily made in the
laboratory, but cannot be extracted from the fruit for separate use.
If the carbon chain contains one or more double linkages we get the
"flowery" perfumes. For instance, here is the symbol of geraniol, the
chief ingredient of otto of roses:
(CH_{3})_{2}C = CHCH_{2}CH_{2}C(CH_{3})_{2} = CHCH_{2}OH
The rose would smell as sweet under another name, but it may be
questioned whether it would stand being called by the name of
dimethyl-2-6-octadiene-2-6-ol-8. Geraniol by oxidation goes into the
aldehyde, citral, which occurs in lemons, oranges and verbena flowers.
Another compound of this group, linalool, is found in lavender, bergamot
and many flowers.
Geraniol, as you would see if you drew up its structural formula in the
way I described in the last chapter, contains a chain of six carbon
atoms, that is, the same number as make a benzene ring. Now if we shake
up geraniol and other compounds of this group (the diolefines) with
diluted sulfuric acid the carbon chain hooks up to form a benzene ring,
but with the other carbon atoms stretched across it; rather too
complicated to depict here. These "bridged rings" of the formula
C_{5}H_{8}, or some multiple of that, constitute the important group of
the terpenes which occur in turpentine and such wild and woodsy things
as sage, lavender, caraway, pine needles and eucalyptus. Going further
in this direction we are led into the realm of the heavy oriental odors,
patchouli, sandalwood, cedar, cubebs, ginger and camphor. Camphor can
now be made directly from turpentine so we may be independent of Formosa
and Borneo.
When we have a six carbon ring without double linkings (cyclo-aliphatic)
or with one or two such, we get soft and delicate perfumes like the
violet (ionone and irone). But when these pass into the benzene ring
with its three double linkages the odor becomes more powerful and so
characteristic that the name "aromatic compound" has been extended to
the entire class of benzene derivatives, although many of them are
odorless. The essential oils of jasmine, orange blossoms, musk,
heliotrope, tuberose, ylang ylang, etc., consist mostly of this class
and can be made from the common source of aromatic compounds, coal tar.
The synthetic flavors and perfumes are made in the same way as the dyes
by starting with some coal-tar product or other crude material and
building up the molecule to the desired complexity. For instance, let us
start with phenol, the ill-smelling and poisonous carbolic acid of
disagreeable associations and evil fame. Treat this to soda-water and it
is transformed into salicylic acid, a white odorless powder, used as a
preservative and as a rheumatism remedy. Add to this methyl alcohol
which is obtained by the destructive distillation of wood and is much
more poisonous than ordinary ethyl alcohol. The alcohol and the acid
heated together will unite with the aid of a little sulfuric acid and we
get what the chemist calls methyl salicylate and other people call oil
of wintergreen, the same as is found in wintergreen berries and birch
bark. We have inherited a taste for this from our pioneer ancestors and
we use it extensively to flavor our soft drinks, gum, tooth paste and
candy, but the Europeans have not yet found out how nice it is.
But, starting with phenol again, let us heat it with caustic alkali and
chloroform. This gives us two new compounds of the same composition, but
differing a little in the order of the atoms. If you refer back to the
diagram of the benzene ring which I gave in the last chapter, you will
see that there are six hydrogen atoms attached to it. Now any or all
these hydrogen atoms may be replaced by other elements or groups and
what the product is depends not only on what the new elements are, but
where they are put. It is like spelling words. The three letters _t_,
_r_ and _a_ mean very different things according to whether they are put
together as _art_, _tar_ or _rat_. Or, to take a more apposite
illustration, every hostess knows that the success of her dinner depends
upon how she seats her guests around the table. So in the case of
aromatic compounds, a little difference in the seating arrangement
around the benzene ring changes the character. The two derivatives of
phenol, which we are now considering, have two substituting groups. One
is--O-H (called the hydroxyl group). The other is--CHO (called the
aldehyde group). If these are opposite (called the para position) we
have an odorless white solid. If they are side by side (called the ortho
position) we have an oil with the odor of meadowsweet. Treating the
odorless solid with methyl alcohol we get audepine (or anisic aldehyde)
which is the perfume of hawthorn blossoms. But treating the other of the
twin products, the fragrant oil, with dry acetic acid ("Perkin's
reaction") we get cumarin, which is the perfume part of the tonka or
tonquin beans that our forefathers used to carry in their snuff boxes.
One ounce of cumarin is equal to four pounds of tonka beans. It smells
sufficiently like vanilla to be used as a substitute for it in cheap
extracts. In perfumery it is known as "new mown hay."
You may remember what I said on a former page about the career of
William Henry Perkin, the boy who loved chemistry better than eating,
and how he discovered the coal-tar dyes. Well, it is also to his
ingenious mind that we owe the starting of the coal-tar perfume business
which has had almost as important a development. Perkin made cumarin in
1868, but this, like the dye industry, escaped from English hands and
flew over the North Sea. Before the war Germany was exporting
$1,500,000 worth of synthetic perfumes a year. Part of these went to
France, where they were mixed and put up in fancy bottles with French
names and sold to Americans at fancy prices.
The real vanilla flavor, vanillin, was made by Tiemann in 1874. At first
it sold for nearly $800 a pound, but now it may be had for $10. How
extensively it is now used in chocolate, ice cream, soda water, cakes
and the like we all know. It should be noted that cumarin and vanillin,
however they may be made, are not imitations, but identical with the
chief constituent of the tonka and vanilla beans and, of course, are
equally wholesome or harmless. But the nice palate can distinguish a
richer flavor in the natural extracts, for they contain small quantities
of other savory ingredients.
A true perfume consists of a large number of odoriferous chemical
compounds mixed in such proportions as to produce a single harmonious
effect upon the sense of smell in a fine brand of perfume may be
compounded a dozen or twenty different ingredients and these, if they
are natural essences, are complex mixtures of a dozen or so distinct
substances. Perfumery is one of the fine arts. The perfumer, like the
orchestra leader, must know how to combine and coördinate his
instruments to produce a desired sensation. A Wagnerian opera requires
103 musicians. A Strauss opera requires 112. Now if the concert manager
wants to economize he will insist upon cutting down on the most
expensive musicians and dropping out some of the others, say, the
supernumerary violinists and the man who blows a single blast or tinkles
a triangle once in the course of the evening. Only the trained ear will
detect the difference and the manager can make more money.
Suppose our mercenary impresario were unable to get into the concert
hall of his famous rival. He would then listen outside the window and
analyze the sound in this fashion: "Fifty per cent. of the sound is made
by the tuba, 20 per cent. by the bass drum, 15 per cent. by the 'cello
and 10 per cent. by the clarinet. There are some other instruments, but
they are not loud and I guess if we can leave them out nobody will know
the difference." So he makes up his orchestra out of these four alone
and many people do not know the difference.
The cheap perfumer goes about it in the same way. He analyzes, for
instance, the otto or oil of roses which cost during the war $400 a
pound--if you could get it at any price--and he finds that the chief
ingredient is geraniol, costing only $5, and next is citronelol, costing
$20; then comes nerol and others. So he makes up a cheap brand of
perfumery out of three or four such compounds. But the genuine oil of
roses, like other natural essences, contains a dozen or more
constituents and to leave many of them out is like reducing an orchestra
to a few loud-sounding instruments or a painting to a three-color print.
A few years ago an attempt was made to make music electrically by
producing separately each kind of sound vibration contained in the
instruments imitated. Theoretically that seems easy, but practically the
tone was not satisfactory because the tones and overtones of a full
orchestra or even of a single violin are too numerous and complex to be
reproduced individually. So the synthetic perfumes have not driven out
the natural perfumes, but, on the contrary, have aided and stimulated
the growth of flowers for essences. The otto or attar of roses, favorite
of the Persian monarchs and romances, has in recent years come chiefly
from Bulgaria. But wars are not made with rosewater and the Bulgars for
the last five years have been engaged in other business than cultivating
their own gardens. The alembic or still was invented by the Arabian
alchemists for the purpose of obtaining the essential oil or attar of
roses. But distillation, even with the aid of steam, is not altogether
satisfactory. For instance, the distilled rose oil contains anywhere
from 10 to 74 per cent. of a paraffin wax (stearopten) that is odorless
and, on the other hand, phenyl-ethyl alcohol, which is an important
constituent of the scent of roses, is broken up in the process of
distillation. So the perfumer can improve on the natural or rather the
distilled oil by leaving out part of the paraffin and adding the missing
alcohol. Even the imported article taken direct from the still is not
always genuine, for the wily Bulgar sometimes "increases the yield" by
sprinkling his roses in the vat with synthetic geraniol just as the wily
Italian pours a barrel of American cottonseed oil over his olives in the
press.
Another method of extracting the scent of flowers is by _enfleurage_,
which takes advantage of the tendency of fats to absorb odors. You know
how butter set beside fish in the ice box will get a fishy flavor. In
_enfleurage_ moist air is carried up a tower passing alternately over
trays of fresh flowers, say violets, and over glass plates covered with
a thin layer of lard. The perfumed lard may then be used as a pomade or
the perfume may be extracted by alcohol.
But many sweet flowers do not readily yield an essential oil, so in such
oases we have to rely altogether upon more or less successful
substitutes. For instance, the perfumes sold under the names of
"heliotrope," "lily of the valley," "lilac," "cyclamen," "honeysuckle,"
"sweet pea," "arbutus," "mayflower" and "magnolia" are not produced from
these flowers but are simply imitations made from other essences,
synthetic or natural. Among the "thousand flowers" that contribute to
the "Eau de Mille Fleurs" are the civet cat, the musk deer and the sperm
whale. Some of the published formulas for "Jockey Club" call for civet
or ambergris and those of "Lavender Water" for musk and civet. The less
said about the origin of these three animal perfumes the better.
Fortunately they are becoming too expensive to use and are being
displaced by synthetic products more agreeable to a refined imagination.
The musk deer may now be saved from extinction since we can make
tri-nitro-butyl-xylene from coal tar. This synthetic musk passes muster
to human nostrils, but a cat will turn up her nose at it. The synthetic
musk is not only much cheaper than the natural, but a dozen times as
strong, or let us say, goes a dozen times as far, for nobody wants it
any stronger.
Such powerful scents as these are only pleasant when highly diluted, yet
they are, as we have seen, essential ingredients of the finest perfumes.
For instance, the natural oil of jasmine and other flowers contain
traces of indols and skatols which have most disgusting odors. Though
our olfactory organs cannot detect their presence yet we perceive their
absence so they have to be put into the artificial perfume. Just so a
brief but violent discord in a piece of music or a glaring color
contrast in a painting may be necessary to the harmony of the whole.
It is absurd to object to "artificial" perfumes, for practically all
perfumes now sold are artificial in the sense of being compounded by the
art of the perfumer and whether the materials he uses are derived from
the flowers of yesteryear or of Carboniferous Era is nobody's business
but his. And he does not tell. The materials can be purchased in the
open market. Various recipes can be found in the books. But every famous
perfumer guards well the secret of his formulas and hands it as a legacy
to his posterity. The ancient Roman family of Frangipani has been made
immortal by one such hereditary recipe. The Farina family still claims
to have the exclusive knowledge of how to make Eau de Cologne. This
famous perfume was first compounded by an Italian, Giovanni Maria
Farina, who came to Cologne in 1709. It soon became fashionable and was
for a time the only scent allowed at some of the German courts. The
various published recipes contain from six to a dozen ingredients,
chiefly the oils of neroli, rosemary, bergamot, lemon and lavender
dissolved in very pure alcohol and allowed to age like wine. The
invention, in 1895, of artificial neroli (orange flowers) has improved
the product.
French perfumery, like the German, had its origin in Italy, when
Catherine de' Medici came to Paris as the bride of Henri II. She
brought with her, among other artists, her perfumer, Sieur Toubarelli,
who established himself in the flowery land of Grasse. Here for four
hundred years the industry has remained rooted and the family formulas
have been handed down from generation to generation. In the city of
Grasse there were at the outbreak of the war fifty establishments making
perfumes. The French perfumer does not confine himself to a single
sense. He appeals as well to sight and sound and association. He adds to
the attractiveness of his creation by a quaintly shaped bottle, an
artistic box and an enticing name such as "Dans les Nues," "Le Coeur de
Jeannette," "Nuit de Chine," "Un Air Embaumé," "Le Vertige," "Bon Vieux
Temps," "L'Heure Bleue," "Nuit d'Amour," "Quelques Fleurs," "Djer-Kiss."
The requirements of a successful scent are very strict. A perfume must
be lasting, but not strong. All its ingredients must continue to
evaporate in the same proportion, otherwise it will change odor and
deteriorate. Scents kill one another as colors do. The minutest trace of
some impurity or foreign odor may spoil the whole effect. To mix the
ingredients in a vessel of any metal but aluminum or even to filter
through a tin funnel is likely to impair the perfume. The odoriferous
compounds are very sensitive and unstable bodies, otherwise they would
have no effect upon the olfactory organ. The combination that would be
suitable for a toilet water would not be good for a talcum powder and
might spoil in a soap. Perfumery is used even in the "scentless" powders
and soaps. In fact it is now used more extensively, if less intensively,
than ever before in the history of the world. During the Unwashed Ages,
commonly called the Dark Ages, between the destruction of the Roman
baths and the construction of the modern bathroom, the art of the
perfumer, like all the fine arts, suffered an eclipse. "The odor of
sanctity" was in highest esteem and what that odor was may be imagined
from reading the lives of the saints. But in the course of centuries the
refinements of life began to seep back into Europe from the East by
means of the Arabs and Crusaders, and chemistry, then chiefly the art of
cosmetics, began to revive. When science, the greatest democratizing
agent on earth, got into action it elevated the poor to the ranks of
kings and priests in the delights of the palate and the nose. We should
not despise these delights, for the pleasure they confer is greater, in
amount at least, than that of the so-called higher senses. We eat three
times a day; some of us drink oftener; few of us visit the concert hall
or the art gallery as often as we do the dining room. Then, too, these
primitive senses have a stronger influence upon our emotional nature
than those acquired later in the course of evolution. As Kipling puts
it:
Smells are surer than sounds or sights
To make your heart-strings crack.
VI
CELLULOSE
Organic compounds, on which our life and living depend, consist chiefly
of four elements: carbon, hydrogen, oxygen and nitrogen. These compounds
are sometimes hard to analyze, but when once the chemist has ascertained
their constitution he can usually make them out of their elements--if he
wants to. He will not want to do it as a business unless it pays and it
will not pay unless the manufacturing process is cheaper than the
natural process. This depends primarily upon the cost of the crude
materials. What, then, is the market price of these four elements?
Oxygen and nitrogen are free as air, and as we have seen in the second
chapter, their direct combination by the electric spark is possible.
Hydrogen is free in the form of water but expensive to extricate by
means of the electric current. But we need more carbon than anything
else and where shall we get that? Bits of crystallized carbon can be
picked up in South Africa and elsewhere, but those who can afford to buy
them prefer to wear them rather than use them in making synthetic food.
Graphite is rare and hard to melt. We must then have recourse to the
compounds of carbon. The simplest of these, carbon dioxide, exists in
the air but only four parts in ten thousand by volume. To extract the
carbon and get it into combination with the other elements would be a
difficult and expensive process. Here, then, we must call in cheap
labor, the cheapest of all laborers, the plants. Pine trees on the
highlands and cotton plants on the lowlands keep their green traps set
all the day long and with the captured carbon dioxide build up
cellulose. If, then, man wants free carbon he can best get it by
charring wood in a kiln or digging up that which has been charred in
nature's kiln during the Carboniferous Era. But there is no reason why
he should want to go back to elemental carbon when he can have it
already combined with hydrogen in the remains of modern or fossil
vegetation. The synthetic products on which modern chemistry prides
itself, such as vanillin, camphor and rubber, are not built up out of
their elements, C, H and O, although they might be as a laboratory
stunt. Instead of that the raw material of the organic chemist is
chiefly cellulose, or the products of its recent or remote destructive
distillation, tar and oil.
It is unnecessary to tell the reader what cellulose is since he now
holds a specimen of it in his hand, pretty pure cellulose except for the
sizing and the specks of carbon that mar the whiteness of its surface.
This utilization of cellulose is the chief cause of the difference
between the modern world and the ancient, for what is called the
invention of printing is essentially the inventing of paper. The Romans
made type to stamp their coins and lead pipes with and if they had had
paper to print upon the world might have escaped the Dark Ages. But the
clay tablets of the Babylonians were cumbersome; the wax tablets of the
Greeks were perishable; the papyrus of the Egyptians was fragile;
parchment was expensive and penning was slow, so it was not until
literature was put on a paper basis that democratic education became
possible. At the present time sheepskin is only used for diplomas,
treaties and other antiquated documents. And even if your diploma is
written in Latin it is likely to be made of sulfated cellulose.
The textile industry has followed the same law of development that I
have indicated in the other industries. Here again we find the three
stages of progress, (1) utilization of natural products, (2) cultivation
of natural products, (3) manufacture of artificial products. The
ancients were dependent upon plants, animals and insects for their
fibers. China used silk, Greece and Rome used wool, Egypt used flax and
India used cotton. In the course of cultivation for three thousand years
the animal and vegetable fibers were lengthened and strengthened and
cheapened. But at last man has risen to the level of the worm and can
spin threads to suit himself. He can now rival the wasp in the making of
paper. He is no longer dependent upon the flax and the cotton plant, but
grinds up trees to get his cellulose. A New York newspaper uses up
nearly 2000 acres of forest a year. The United States grinds up about
five million cords of wood a year in the manufacture of pulp for paper
and other purposes.
In making "mechanical pulp" the blocks of wood, mostly spruce and
hemlock, are simply pressed sidewise of the grain against wet
grindstones. But in wood fiber the cellulose is in part combined with
lignin, which is worse than useless. To break up the ligno-cellulose
combine chemicals are used. The logs for this are not ground fine, but
cut up by disk chippers. The chips are digested for several hours under
heat and pressure with acid or alkali. There are three processes in
vogue. In the most common process the reagent is calcium sulfite, made
by passing sulfur fumes (SO_{2}) into lime water. In another process a
solution of caustic of soda is used to disintegrate the wood. The third,
known as the "sulfate" process, should rather be called the sulfide
process since the active agent is an alkaline solution of sodium sulfide
made by roasting sodium sulfate with the carbonaceous matter extracted
from the wood. This sulfate process, though the most recent of the
three, is being increasingly employed in this country, for by means of
it the resinous pine wood of the South can be worked up and the final
product, known as kraft paper because it is strong, is used for
wrapping.
But whatever the process we get nearly pure cellulose which, as you can
see by examining this page under a microscope, consists of a tangled web
of thin white fibers, the remains of the original cell walls. Owing to
the severe treatment it has undergone wood pulp paper does not last so
long as the linen rag paper used by our ancestors. The pages of the
newspapers, magazines and books printed nowadays are likely to become
brown and brittle in a few years, no great loss for the most part since
they have served their purpose, though it is a pity that a few copies of
the worst of them could not be printed on permanent paper for
preservation in libraries so that future generations could congratulate
themselves on their progress in civilization.
But in our absorption in the printed page we must not forget the other
uses of paper. The paper clothing, so often prophesied, has not yet
arrived. Even paper collars have gone out of fashion--if they ever were
in. In Germany during the war paper was used for socks, shirts and shoes
as well as handkerchiefs and napkins but it could not stand wear and
washing. Our sanitary engineers have set us to drinking out of
sharp-edged paper cups and we blot our faces instead of wiping them.
Twine is spun of paper and furniture made of the twine, a rival of
rattan. Cloth and matting woven of paper yarn are being used for burlap
and grass in the making of bags and suitcases.
Here, however, we are not so much interested in manufactures of
cellulose itself, that is, wood, paper and cotton, as we are in its
chemical derivatives. Cellulose, as we can see from the symbol,
C_{6}H_{10}O_{5}, is composed of the three elements of carbon, hydrogen
and oxygen. These are present in the same proportion as in starch
(C_{6}H_{10}O_{5}), while glucose or grape sugar (C_{6}H_{12}O_{6}) has
one molecule of water more. But glucose is soluble in cold water and
starch is soluble in hot, while cellulose is soluble in neither.
Consequently cellulose cannot serve us for food, although some of the
vegetarian animals, notably the goat, have a digestive apparatus that
can handle it. In Finland and Germany birch wood pulp and straw were
used not only as an ingredient of cattle food but also put into war
bread. It is not likely, however, that the human stomach even under the
pressure of famine is able to get much nutriment out of sawdust. But by
digesting with dilute acid sawdust can be transformed into sugars and
these by fermentation into alcohol, so it would be possible for a man
after he has read his morning paper to get drunk on it.
If the cellulose, instead of being digested a long time in dilute acid,
is dipped into a solution of sulfuric acid (50 to 80 per cent.) and then
washed and dried it acquires a hard, tough and translucent coating that
makes it water-proof and grease-proof. This is the "parchment paper"
that has largely replaced sheepskin. Strong alkali has a similar effect
to strong acid. In 1844 John Mercer, a Lancashire calico printer,
discovered that by passing cotton cloth or yarn through a cold 30 per
cent. solution of caustic soda the fiber is shortened and strengthened.
For over forty years little attention was paid to this discovery, but
when it was found that if the material was stretched so that it could
not shrink on drying the twisted ribbons of the cotton fiber were
changed into smooth-walled cylinders like silk, the process came into
general use and nowadays much that passes for silk is "mercerized"
cotton.
Another step was taken when Cross of London discovered that when the
mercerized cotton was treated with carbon disulfide it was dissolved to
a yellow liquid. This liquid contains the cellulose in solution as a
cellulose xanthate and on acidifying or heating the cellulose is
recovered in a hydrated form. If this yellow solution of cellulose is
squirted out of tubes through extremely minute holes into acidulated
water, each tiny stream becomes instantly solidified into a silky thread
which may be spun and woven like that ejected from the spinneret of the
silkworm. The origin of natural silk, if we think about it, rather
detracts from the pleasure of wearing it, and if "he who needlessly
sets foot upon a worm" is to be avoided as a friend we must hope that
the advance of the artificial silk industry will be rapid enough to
relieve us of the necessity of boiling thousands of baby worms in their
cradles whenever we want silk stockings.
On a plain rush hurdle a silkworm lay
When a proud young princess came that way.
The haughty daughter of a lordly king
Threw a sidelong glance at the humble thing,
Little thinking she walked in pride
In the winding sheet where the silkworm died.
But so far we have not reached a stage where we can altogether dispense
with the services of the silkworm. The viscose threads made by the
process look as well as silk, but they are not so strong, especially
when wet.
Besides the viscose method there are several other methods of getting
cellulose into solution so that artificial fibers may be made from it. A
strong solution of zinc chloride will serve and this process used to be
employed for making the threads to be charred into carbon filaments for
incandescent bulbs. Cellulose is also soluble in an ammoniacal solution
of copper hydroxide. The liquid thus formed is squirted through a fine
nozzle into a precipitating solution of caustic soda and glucose, which
brings back the cellulose to its original form.
In the chapter on explosives I explained how cellulose treated with
nitric acid in the presence of sulfuric acid was nitrated. The cellulose
molecule having three hydroxyl (--OH) groups, can take up one, two or
three nitrate groups (--ONO_{2}). The higher nitrates are known as
guncotton and form the basis of modern dynamite and smokeless powder.
The lower nitrates, known as pyroxylin, are less explosive, although
still very inflammable. All these nitrates are, like the original
cellulose, insoluble in water, but unlike the original cellulose,
soluble in a mixture of ether and alcohol. The solution is called
collodion and is now in common use to spread a new skin over a wound.
The great war might be traced back to Nobel's cut finger. Alfred Nobel
was a Swedish chemist--and a pacifist. One day while working in the
laboratory he cut his finger, as chemists are apt to do, and, again as
chemists are apt to do, he dissolved some guncotton in ether-alcohol and
swabbed it on the wound. At this point, however, his conduct diverges
from the ordinary, for instead of standing idle, impatiently waving his
hand in the air to dry the film as most people, including chemists, are
apt to do, he put his mind on it and it occurred to him that this sticky
stuff, slowly hardening to an elastic mass, might be just the thing he
was hunting as an absorbent and solidifier of nitroglycerin. So instead
of throwing away the extra collodion that he had made he mixed it with
nitroglycerin and found that it set to a jelly. The "blasting gelatin"
thus discovered proved to be so insensitive to shock that it could be
safely transported or fired from a cannon. This was the first of the
high explosives that have been the chief factor in modern warfare.
But on the whole, collodion has healed more wounds than it has caused
besides being of infinite service to mankind otherwise. It has made
modern photography possible, for the film we use in the camera and
moving picture projector consists of a gelatin coating on a pyroxylin
backing. If collodion is forced through fine glass tubes instead of
through a slit, it comes out a thread instead of a film. If the
collodion jet is run into a vat of cold water the ether and alcohol
dissolve; if it is run into a chamber of warm air they evaporate. The
thread of nitrated cellulose may be rendered less inflammable by taking
out the nitrate groups by treatment with ammonium or calcium sulfide.
This restores the original cellulose, but now it is an endless thread of
any desired thickness, whereas the native fiber was in size and length
adapted to the needs of the cottonseed instead of the needs of man. The
old motto, "If you want a thing done the way you want it you must do it
yourself," explains why the chemist has been called in to supplement the
work of nature in catering to human wants.
Instead of nitric acid we may use strong acetic acid to dissolve the
cotton. The resulting cellulose acetates are less inflammable than the
nitrates, but they are more brittle and more expensive. Motion picture
films made from them can be used in any hall without the necessity of
imprisoning the operator in a fire-proof box where if anything happens
he can burn up all by himself without disturbing the audience. The
cellulose acetates are being used for auto goggles and gas masks as well
as for windows in leather curtains and transparent coverings for index
cards. A new use that has lately become important is the varnishing of
aeroplane wings, as it does not readily absorb water or catch fire and
makes the cloth taut and air-tight. Aeroplane wings can be made of
cellulose acetate sheets as transparent as those of a dragon-fly and not
easy to see against the sky.
The nitrates, sulfates and acetates are the salts or esters of the
respective acids, but recently true ethers or oxides of cellulose have
been prepared that may prove still better since they contain no acid
radicle and are neutral and stable.
These are in brief the chief processes for making what is commonly but
quite improperly called "artificial silk." They are not the same
substance as silkworm silk and ought not to be--though they sometimes
are--sold as such. They are none of them as strong as the silk fiber
when wet, although if I should venture to say which of the various makes
weakens the most on wetting I should get myself into trouble. I will
only say that if you have a grudge against some fisherman give him a fly
line of artificial silk, 'most any kind.
The nitrate process was discovered by Count Hilaire de Chardonnet while
he was at the Polytechnic School of Paris, and he devoted his life and
his fortune trying to perfect it. Samples of the artificial silk were
exhibited at the Paris Exposition in 1889 and two years later he started
a factory at Basançon. In 1892, Cross and Bevan, English chemists,
discovered the viscose or xanthate process, and later the acetate
process. But although all four of these processes were invented
in France and England, Germany reaped most benefit from the new
industry, which was bringing into that country $6,000,000 a year
before the war. The largest producer in the world was the Vereinigte
Glanzstoff-Fabriken of Elberfeld, which was paying annual dividends of
34 per cent. in 1914.
The raw materials, as may be seen, are cheap and abundant, merely
cellulose, salt, sulfur, carbon, air and water. Any kind of cellulose
can be used, cotton waste, rags, paper, or even wood pulp. The processes
are various, the names of the products are numerous and the uses are
innumerable. Even the most inattentive must have noticed the widespread
employment of these new forms of cellulose. We can buy from a street
barrow for fifteen cents near-silk neckties that look as well as those
sold for seventy-five. As for wear--well, they all of them wear till
after we get tired of wearing them. Paper "vulcanized" by being run
through a 30 per cent. solution of zinc chloride and subjected to
hydraulic pressure comes out hard and horny and may be used for trunks
and suit cases. Viscose tubes for sausage containers are more sanitary
and appetizing than the customary casings. Viscose replaces ramie or
cotton in the Welsbach gas mantles. Viscose film, transparent and a
thousandth of an inch thick (cellophane), serves for candy wrappers.
Cellulose acetate cylinders spun out of larger orifices than silk are
trying--not very successfully as yet--to compete with hog's bristles and
horsehair. Stir powdered metals into the cellulose solution and you have
the Bayko yarn. Bayko (from the manufacturers, Farbenfabriken vorm.
Friedr. Bayer and Company) is one of those telescoped names like Socony,
Nylic, Fominco, Alco, Ropeco, Ripans, Penn-Yan, Anzac, Dagor, Dora and
Cadets, which will be the despair of future philologers.
[Illustration: A PAPER MILL IN ACTION
This photograph was taken in the barking room of the big pulp mill of
the Great Northern Paper Company at Millinocket, Maine]
[Illustration: CELLULOSE FROM WOOD PULP
This is now made into a large variety of useful articles of which a few
examples are here pictured]
Soluble cellulose may enable us in time to dispense with the weaver as
well as the silkworm. It may by one operation give us fabrics instead of
threads. A machine has been invented for manufacturing net and lace, the
liquid material being poured on one side of a roller and the fabric
being reeled off on the other side. The process seems capable of
indefinite extension and application to various sorts of woven, knit and
reticulated goods. The raw material is cotton waste and the finished
fabric is a good substitute for silk. As in the process of making
artificial silk the cellulose is dissolved in a cupro-ammoniacal
solution, but instead of being forced out through minute openings to
form threads, as in that process, the paste is allowed to flow upon a
revolving cylinder which is engraved with the pattern of the desired
textile. A scraper removes the excess and the turning of the cylinder
brings the paste in the engraved lines down into a bath which solidifies
it.
Tulle or net is now what is chiefly being turned out, but the engraved
design may be as elaborate and artistic as desired, and various
materials can be used. Since the threads wherever they cross are united,
the fabric is naturally stronger than the ordinary. It is all of a piece
and not composed of parts. In short, we seem to be on the eve of a
revolution in textiles that is the same as that taking place in building
materials. Our concrete structures, however great, are all one stone.
They are not built up out of blocks, but cast as a whole.
Lace has always been the aristocrat among textiles. It has maintained
its exclusiveness hitherto by being based upon hand labor. In no other
way could one get so much painful, patient toil put into such a light
and portable form. A filmy thing twined about a neck or dropping from a
wrist represented years of work by poor peasant girls or pallid, unpaid
nuns. A visit to a lace factory, even to the public rooms where the
wornout women were not to be seen, is enough to make one resolve never
to purchase any such thing made by hand again. But our good resolutions
do not last long and in time we forget the strained eyes and bowed
backs, or, what is worse, value our bit of lace all the more because it
means that some poor woman has put her life and health into it, netting
and weaving, purling and knotting, twining and twisting, throwing and
drawing, thread by thread, day after day, until her eyes can no longer
see and her fingers have become stiffened.
But man is not naturally cruel. He does not really enjoy being a slave
driver, either of human or animal slaves, although he can be hardened to
it with shocking ease if there seems no other way of getting what he
wants. So he usually welcomes that Great Liberator, the Machine. He
prefers to drive the tireless engine than to whip the straining horses.
He had rather see the farmer riding at ease in a mowing machine than
bending his back over a scythe.
The Machine is not only the Great Liberator, it is the Great Leveler
also. It is the most powerful of the forces for democracy. An
aristocracy can hardly be maintained except by distinction in dress, and
distinction in dress can only be maintained by sumptuary laws or
costliness. Sumptuary laws are unconstitutional in this country, hence
the stress laid upon costliness. But machinery tends to bring styles
and fabrics within the reach of all. The shopgirl is almost as well
dressed on the street as her rich customer. The man who buys ready-made
clothing is only a few weeks behind the vanguard of the fashion. There
is often no difference perceptible to the ordinary eye between cheap and
high-priced clothing once the price tag is off. Jewels as a portable
form of concentrated costliness have been in favor from the earliest
ages, but now they are losing their factitious value through the advance
of invention. Rubies of unprecedented size, not imitation, but genuine
rubies, can now be manufactured at reasonable rates. And now we may hope
that lace may soon be within the reach of all, not merely lace of the
established forms, but new and more varied and intricate and beautiful
designs, such as the imagination has been able to conceive, but the hand
cannot execute.
Dissolving nitrocellulose in ether and alcohol we get the collodion
varnish that we are all familiar with since we have used it on our cut
fingers. Spread it on cloth instead of your skin and it makes a very
good leather substitute. As we all know to our cost the number of
animals to be skinned has not increased so rapidly in recent years as
the number of feet to be shod. After having gone barefoot for a million
years or so the majority of mankind have decided to wear shoes and this
change in fashion comes at a time, roughly speaking, when pasture land
is getting scarce. Also there are books to be bound and other new things
to be done for which leather is needed. The war has intensified the
stringency; so has feminine fashion. The conventions require that the
shoe-tops extend nearly to skirt-bottom and this means that an inch or
so must be added to the shoe-top every year. Consequent to this rise in
leather we have to pay as much for one shoe as we used to pay for a
pair.
Here, then, is a chance for Necessity to exercise her maternal function.
And she has responded nobly. A progeny of new substances have been
brought forth and, what is most encouraging to see, they are no longer
trying to worm their way into favor as surreptitious surrogates under
the names of "leatheret," "leatherine," "leatheroid" and
"leather-this-or-that" but come out boldly under names of their own
coinage and declare themselves not an imitation, not even a substitute,
but "better than leather." This policy has had the curious result of
compelling the cowhide men to take full pages in the magazines to call
attention to the forgotten virtues of good old-fashioned sole-leather!
There are now upon the market synthetic shoes that a vegetarian could
wear with a clear conscience. The soles are made of some rubber
composition; the uppers of cellulose fabric (canvas) coated with a
cellulose solution such as I have described.
Each firm keeps its own process for such substance a dead secret, but
without prying into these we can learn enough to satisfy our legitimate
curiosity. The first of the artificial fabrics was the old-fashioned and
still indispensable oil-cloth, that is canvas painted or printed with
linseed oil carrying the desired pigments. Linseed oil belongs to the
class of compounds that the chemist calls "unsaturated" and the
psychologist would call "unsatisfied." They take up oxygen from the air
and become solid, hence are called the "drying oils," although this
does not mean that they lose water, for they have not any to lose.
Later, ground cork was mixed with the linseed oil and then it went by
its Latin name, "linoleum."
The next step was to cut loose altogether from the natural oils and use
for the varnish a solution of some of the cellulose esters, usually the
nitrate (pyroxylin or guncotton), more rarely the acetate. As a solvent
the ether-alcohol mixture forming collodion was, as we have seen, the
first to be employed, but now various other solvents are in use, among
them castor oil, methyl alcohol, acetone, and the acetates of amyl or
ethyl. Some of these will be recognized as belonging to the fruit
essences that we considered in Chapter V, and doubtless most of us have
perceived an odor as of over-ripe pears, bananas or apples mysteriously
emanating from a newly lacquered radiator. With powdered bronze,
imitation gold, aluminum or something of the kind a metallic finish can
be put on any surface.
Canvas coated or impregnated with such soluble cellulose gives us new
flexible and durable fabrics that have other advantages over leather
besides being cheaper and more abundant. Without such material for
curtains and cushions the automobile business would have been sorely
hampered. It promises to provide us with a book binding that will not
crumble to powder in the course of twenty years. Linen collars may be
water-proofed and possibly Dame Fashion--being a fickle lady--may some
day relent and let us wear such sanitary and economical neckwear. For
shoes, purses, belts and the like the cellulose varnish or veneer is
usually colored and stamped to resemble the grain of any kind of
leather desired, even snake or alligator.
If instead of dissolving the cellulose nitrate and spreading it on
fabric we combine it with camphor we get celluloid, a plastic solid
capable of innumerable applications. But that is another story and must
be reserved for the next chapter.
But before leaving the subject of cellulose proper I must refer back
again to its chief source, wood. We inherited from the Indians a
well-wooded continent. But the pioneer carried an ax on his shoulder and
began using it immediately. For three hundred years the trees have been
cut down faster than they could grow, first to clear the land, next for
fuel, then for lumber and lastly for paper. Consequently we are within
sight of a shortage of wood as we are of coal and oil. But the coal and
oil are irrecoverable while the wood may be regrown, though it would
require another three hundred years and more to grow some of the trees
we have cut down. For fuel a pound of coal is about equal to two pounds
of wood, and a pound of gasoline to three pounds of wood in heating
value, so there would be a great loss in efficiency and economy if the
world had to go back to a wood basis. But when that time shall come, as,
of course, it must come some time, the wood will doubtless not be burned
in its natural state but will be converted into hydrogen and carbon
monoxide in a gas producer or will be distilled in closed ovens giving
charcoal and gas and saving the by-products, the tar and acid liquors.
As it is now the lumberman wastes two-thirds of every tree he cuts down.
The rest is left in the forest as stump and tops or thrown out at the
mill as sawdust and slabs. The slabs and other scraps may be used as
fuel or worked up into small wood articles like laths and clothes-pins.
The sawdust is burned or left to rot. But it is possible, although it
may not be profitable, to save all this waste.
In a former chapter I showed the advantages of the introduction of
by-product coke-ovens. The same principle applies to wood as to coal. If
a cord of wood (128 cubic feet) is subjected to a process of destructive
distillation it yields about 50 bushels of charcoal, 11,500 cubic feet
of gas, 25 gallons of tar, 10 gallons of crude wood alcohol and 200
pounds of crude acetate of lime. Resinous woods such as pine and fir
distilled with steam give turpentine and rosin. The acetate of lime
gives acetic acid and acetone. The wood (methyl) alcohol is almost as
useful as grain (ethyl) alcohol in arts and industry and has the
advantage of killing off those who drink it promptly instead of slowly.
The chemist is an economical soul. He is never content until he has
converted every kind of waste product into some kind of profitable
by-product. He now has his glittering eye fixed upon the mountains of
sawdust that pile up about the lumber mills. He also has a notion that
he can beat lumber for some purposes.
VII
SYNTHETIC PLASTICS
In the last chapter I told how Alfred Nobel cut his finger and, daubing
it over with collodion, was led to the discovery of high explosive,
dynamite. I remarked that the first part of this process--the hurting
and the healing of the finger--might happen to anybody but not everybody
would be led to discovery thereby. That is true enough, but we must not
think that the Swedish chemist was the only observant man in the world.
About this same time a young man in Albany, named John Wesley Hyatt, got
a sore finger and resorted to the same remedy and was led to as great a
discovery. His father was a blacksmith and his education was confined to
what he could get at the seminary of Eddytown, New York, before he was
sixteen. At that age he set out for the West to make his fortune. He
made it, but after a long, hard struggle. His trade of typesetter gave
him a living in Illinois, New York or wherever he wanted to go, but he
was not content with his wages or his hours. However, he did not strike
to reduce his hours or increase his wages. On the contrary, he increased
his working time and used it to increase his income. He spent his nights
and Sundays in making billiard balls, not at all the sort of thing you
would expect of a young man of his Christian name. But working with
billiard balls is more profitable than playing with them--though that
is not the sort of thing you would expect a man of my surname to say.
Hyatt had seen in the papers an offer of a prize of $10,000 for the
discovery of a satisfactory substitute for ivory in the making of
billiard balls and he set out to get that prize. I don't know whether he
ever got it or not, but I have in my hand a newly published circular
announcing that Mr. Hyatt has now perfected a process for making
billiard balls "better than ivory." Meantime he has turned out several
hundred other inventions, many of them much more useful and profitable,
but I imagine that he takes less satisfaction in any of them than he
does in having solved the problem that he undertook fifty years ago.
The reason for the prize was that the game on the billiard table was
getting more popular and the game in the African jungle was getting
scarcer, especially elephants having tusks more than 2-7/16 inches in
diameter. The raising of elephants is not an industry that promises as
quick returns as raising chickens or Belgian hares. To make a ball
having exactly the weight, color and resiliency to which billiard
players have become accustomed seemed an impossibility. Hyatt tried
compressed wood, but while he did not succeed in making billiard balls
he did build up a profitable business in stamped checkers and dominoes.
Setting type in the way they did it in the sixties was hard on the
hands. And if the skin got worn thin or broken the dirty lead type were
liable to infect the fingers. One day in 1863 Hyatt, finding his fingers
were getting raw, went to the cupboard where was kept the "liquid
cuticle" used by the printers. But when he got there he found it was
bare, for the vial had tipped over--you know how easily they tip
over--and the collodion had run out and solidified on the shelf.
Possibly Hyatt was annoyed, but if so he did not waste time raging
around the office to find out who tipped over that bottle. Instead he
pulled off from the wood a bit of the dried film as big as his thumb
nail and examined it with that "'satiable curtiosity," as Kipling calls
it, which is characteristic of the born inventor. He found it tough and
elastic and it occurred to him that it might be worth $10,000. It turned
out to be worth many times that.
Collodion, as I have explained in previous chapters, is a solution in
ether and alcohol of guncotton (otherwise known as pyroxylin or
nitrocellulose), which is made by the action of nitric acid on cotton.
Hyatt tried mixing the collodion with ivory powder, also using it to
cover balls of the necessary weight and solidity, but they did not work
very well and besides were explosive. A Colorado saloon keeper wrote in
to complain that one of the billiard players had touched a ball with a
lighted cigar, which set it off and every man in the room had drawn his
gun.
The trouble with the dissolved guncotton was that it could not be
molded. It did not swell up and set; it merely dried up and shrunk. When
the solvent evaporated it left a wrinkled, shriveled, horny film,
satisfactory to the surgeon but not to the man who wanted to make balls
and hairpins and knife handles out of it. In England Alexander Parkes
began working on the problem in 1855 and stuck to it for ten years
before he, or rather his backers, gave up. He tried mixing in various
things to stiffen up the pyroxylin. Of these, camphor, which he tried in
1865, worked the best, but since he used castor oil to soften the mass
articles made of "parkesine" did not hold up in all weathers.
Another Englishman, Daniel Spill, an associate of Parkes, took up the
problem where he had dropped it and turned out a better product,
"xylonite," though still sticking to the idea that castor oil was
necessary to get the two solids, the guncotton and the camphor,
together.
But Hyatt, hearing that camphor could be used and not knowing enough
about what others had done to follow their false trails, simply mixed
his camphor and guncotton together without any solvent and put the
mixture in a hot press. The two solids dissolved one another and when
the press was opened there was a clear, solid, homogeneous block
of--what he named--"celluloid." The problem was solved and in the
simplest imaginable way. Tissue paper, that is, cellulose, is treated
with nitric acid in the presence of sulfuric acid. The nitration is not
carried so far as to produce the guncotton used in explosives but only
far enough to make a soluble nitrocellulose or pyroxylin. This is pulped
and mixed with half the quantity of camphor, pressed into cakes and
dried. If this mixture is put into steam-heated molds and subjected to
hydraulic pressure it takes any desired form. The process remains
essentially the same as was worked out by the Hyatt brothers in the
factory they set up in Newark in 1872 and some of their original
machines are still in use. But this protean plastic takes innumerable
forms and almost as many names. Each factory has its own secrets and
lays claim to peculiar merits. The fundamental product itself is not
patented, so trade names are copyrighted to protect the product. I have
already mentioned three, "parkesine," "xylonite" and "celluloid," and I
may add, without exhausting the list of species belonging to this genus,
"viscoloid," "lithoxyl," "fiberloid," "coraline," "eburite,"
"pulveroid," "ivorine," "pergamoid," "duroid," "ivortus," "crystalloid,"
"transparene," "litnoid," "petroid," "pasbosene," "cellonite" and
"pyralin."
Celluloid can be given any color or colors by mixing in aniline dyes or
metallic pigments. The color may be confined to the surface or to the
interior or pervade the whole. If the nitrated tissue paper is bleached
the celluloid is transparent or colorless. In that case it is necessary
to add an antacid such as urea to prevent its getting yellow or opaque.
To make it opaque and less inflammable oxides or chlorides of zinc,
aluminum, magnesium, etc., are mixed in.
Without going into the question of their variations and relative merits
we may consider the advantages of the pyroxylin plastics in general.
Here we have a new substance, the product of the creative genius of man,
and therefore adaptable to his needs. It is hard but light, tough but
elastic, easily made and tolerably cheap. Heated to the boiling point of
water it becomes soft and flexible. It can be turned, carved, ground,
polished, bent, pressed, stamped, molded or blown. To make a block of
any desired size simply pile up the sheets and put them in a hot press.
To get sheets of any desired thickness, simply shave them off the block.
To make a tube of any desired size, shape or thickness squirt out the
mixture through a ring-shaped hole or roll the sheets around a hot bar.
Cut the tube into sections and you have rings to be shaped and stamped
into box bodies or napkin rings. Print words or pictures on a celluloid
sheet, put a thin transparent sheet over it and weld them together, then
you have something like the horn book of our ancestors, but better.
Nowadays such things as celluloid and pyralin can be sold under their
own name, but in the early days the artificial plastics, like every new
thing, had to resort to _camouflage_, a very humiliating expedient since
in some cases they were better than the material they were forced to
imitate. Tortoise shell, for instance, cracks, splits and twists, but a
"tortoise shell" comb of celluloid looks as well and lasts better. Horn
articles are limited to size of the ceratinous appendages that can be
borne on the animal's head, but an imitation of horn can be made of any
thickness by wrapping celluloid sheets about a cone. Ivory, which also
has a laminated structure, may be imitated by rolling together alternate
white opaque and colorless translucent sheets. Some of the sheets are
wrinkled in order to produce the knots and irregularities of the grain
of natural ivory. Man's chief difficulty in all such work is to imitate
the imperfections of nature. His whites are too white, his surfaces are
too smooth, his shapes are too regular, his products are too pure.
The precious red coral of the Mediterranean can be perfectly imitated by
taking a cast of a coral branch and filling in the mold with celluloid
of the same color and hardness. The clear luster of amber, the dead
black of ebony, the cloudiness of onyx, the opalescence of alabaster,
the glow of carnelian--once confined to the selfish enjoyment of the
rich--are now within the reach of every one, thanks to this chameleon
material. Mosaics may be multiplied indefinitely by laying together
sheets and sticks of celluloid, suitably cut and colored to make up the
picture, fusing the mass, and then shaving off thin layers from the end.
That _chef d'oeuvre_ of the Venetian glass makers, the Battle of Isus,
from the House of the Faun in Pompeii, can be reproduced as fast as the
machine can shave them off the block. And the tesserae do not fall out
like those you bought on the Rialto.
The process thus does for mosaics, ivory and coral what printing does
for pictures. It is a mechanical multiplier and only by such means can
we ever attain to a state of democratic luxury. The product, in cases
where the imitation is accurate, is equally valuable except to those who
delight in thinking that coral insects, Italian craftsmen and elephants
have been laboring for years to put a trinket into their hands. The Lord
may be trusted to deal with such selfish souls according to their
deserts.
But it is very low praise for a synthetic product that it can pass
itself off, more or less acceptably, as a natural product. If that is
all we could do without it. It must be an improvement in some respects
on anything to be found in nature or it does not represent a real
advance. So celluloid and its congeners are not confined to the shapes
of shell and coral and crystal, or to the grain of ivory and wood and
horn, the colors of amber and amethyst and lapis lazuli, but can be
given forms and textures and tints that were never known before 1869.
Let me see now, have I mentioned all the uses of celluloid? Oh, no,
there are handles for canes, umbrellas, mirrors and brushes, knives,
whistles, toys, blown animals, card cases, chains, charms, brooches,
badges, bracelets, rings, book bindings, hairpins, campaign buttons,
cuff and collar buttons, cuffs, collars and dickies, tags, cups, knobs,
paper cutters, picture frames, chessmen, pool balls, ping pong balls,
piano keys, dental plates, masks for disfigured faces, penholders,
eyeglass frames, goggles, playing cards--and you can carry on the list
as far as you like.
Celluloid has its disadvantages. You may mold, you may color the stuff
as you will, the scent of the camphor will cling around it still. This
is not usually objectionable except where the celluloid is trying to
pass itself off for something else, in which case it deserves no
sympathy. It is attacked and dissolved by hot acids and alkalies. It
softens up when heated, which is handy in shaping it though not so
desirable afterward. But the worst of its failings is its
combustibility. It is not explosive, but it takes fire from a flame and
burns furiously with clouds of black smoke.
But celluloid is only one of many plastic substances that have been
introduced to the present generation. A new and important group of them
is now being opened up, the so-called "condensation products." If you
will take down any old volume of chemical research you will find
occasionally words to this effect: "The reaction resulted in nothing but
an insoluble resin which was not further investigated." Such a passage
would be marked with a tear if chemists were given to crying over their
failures. For it is the epitaph of a buried hope. It likely meant the
loss of months of labor. The reason the chemist did not do anything
further with the gummy stuff that stuck up his test tube was because he
did not know what to do with it. It could not be dissolved, it could not
be crystallized, it could not be distilled, therefore it could not be
purified, analyzed and identified.
What had happened was in most cases this. The molecule of the compound
that the chemist was trying to make had combined with others of its kind
to form a molecule too big to be managed by such means. Financiers call
the process a "merger." Chemists call it "polymerization." The resin was
a molecular trust, indissoluble, uncontrollable and contaminating
everything it touched.
But chemists--like governments--have learned wisdom in recent years.
They have not yet discovered in all cases how to undo the process of
polymerization, or, if you prefer the financial phrase, how to
unscramble the eggs. But they have found that these molecular mergers
are very useful things in their way. For instance there is a liquid
known as isoprene (C_{5}H_{8}). This on heating or standing turns into a
gum, that is nothing less than rubber, which is some multiple of
C_{5}H_{8}.
For another instance there is formaldehyde, an acrid smelling gas, used
as a disinfectant. This has the simplest possible formula for a
carbohydrate, CH_{2}O. But in the leaf of a plant this molecule
multiplies itself by six and turns into a sweet solid glucose
(C_{6}H_{12}O_{6}), or with the loss of water into starch
(C_{6}H_{10}O_{5}) or cellulose (C_{6}H_{10}O_{5}).
But formaldehyde is so insatiate that it not only combines with itself
but seizes upon other substances, particularly those having an
acquisitive nature like its own. Such a substance is carbolic acid
(phenol) which, as we all know, is used as a disinfectant like
formaldehyde because it, too, has the power of attacking decomposable
organic matter. Now Prof. Adolf von Baeyer discovered in 1872 that when
phenol and formaldehyde were brought into contact they seized upon one
another and formed a combine of unusual tenacity, that is, a resin. But
as I have said, chemists in those days were shy of resins. Kleeberg in
1891 tried to make something out of it and W.H. Story in 1895 went so
far as to name the product "resinite," but nothing came of it until 1909
when L.H. Baekeland undertook a serious and systematic study of this
reaction in New York. Baekeland was a Belgian chemist, born at Ghent in
1863 and professor at Bruges. While a student at Ghent he took up
photography as a hobby and began to work on the problem of doing away
with the dark-room by producing a printing paper that could be developed
under ordinary light. When he came over to America in 1889 he brought
his idea with him and four years later turned out "Velox," with which
doubtless the reader is familiar. Velox was never patented because, as
Dr. Baekeland explained in his speech of acceptance of the Perkin medal
from the chemists of America, lawsuits are too expensive. Manufacturers
seem to be coming generally to the opinion that a synthetic name
copyrighted as a trademark affords better protection than a patent.
Later Dr. Baekeland turned his attention to the phenol condensation
products, working gradually up from test tubes to ton vats according to
his motto: "Make your mistakes on a small scale and your profits on a
large scale." He found that when equal weights of phenol and
formaldehyde were mixed and warmed in the presence of an alkaline
catalytic agent the solution separated into two layers, the upper
aqueous and the lower a resinous precipitate. This resin was soft,
viscous and soluble in alcohol or acetone. But if it was heated under
pressure it changed into another and a new kind of resin that was hard,
inelastic, unplastic, infusible and insoluble. The chemical name of this
product is "polymerized oxybenzyl methylene glycol anhydride," but
nobody calls it that, not even chemists. It is called "Bakelite" after
its inventor.
The two stages in its preparation are convenient in many ways. For
instance, porous wood may be soaked in the soft resin and then by heat
and pressure it is changed to the bakelite form and the wood comes out
with a hard finish that may be given the brilliant polish of Japanese
lacquer. Paper, cardboard, cloth, wood pulp, sawdust, asbestos and the
like may be impregnated with the resin, producing tough and hard
material suitable for various purposes. Brass work painted with it and
then baked at 300° F. acquires a lacquered surface that is unaffected by
soap. Forced in powder or sheet form into molds under a pressure of 1200
to 2000 pounds to the square inch it takes the most delicate
impressions. Billiard balls of bakelite are claimed to be better than
ivory because, having no grain, they do not swell unequally with heat
and humidity and so lose their sphericity. Pipestems and beads of
bakelite have the clear brilliancy of amber and greater strength.
Fountain pens made of it are transparent so you can see how much ink you
have left. A new and enlarging field for bakelite and allied products is
the making of noiseless gears for automobiles and other machinery, also
of air-plane propellers.
Celluloid is more plastic and elastic than bakelite. It is therefore
more easily worked in sheets and small objects. Celluloid can be made
perfectly transparent and colorless while bakelite is confined to the
range between a clear amber and an opaque brown or black. On the other
hand bakelite has the advantage in being tasteless, odorless, inert,
insoluble and non-inflammable. This last quality and its high electrical
resistance give bakelite its chief field of usefulness. Electricity was
discovered by the Greeks, who found that amber (_electron_) when rubbed
would pick up straws. This means simply that amber, like all such
resinous substances, natural or artificial, is a non-conductor or
di-electric and does not carry off and scatter the electricity collected
on the surface by the friction. Bakelite is used in its liquid form for
impregnating coils to keep the wires from shortcircuiting and in its
solid form for commutators, magnetos, switch blocks, distributors, and
all sorts of electrical apparatus for automobiles, telephones, wireless
telegraphy, electric lighting, etc.
Bakelite, however, is only one of an indefinite number of such
condensation products. As Baeyer said long ago: "It seems that all the
aldehydes will, under suitable circumstances, unite with the aromatic
hydrocarbons to form resins." So instead of phenol, other coal tar
products such as cresol, naphthol or benzene itself may be used. The
carbon links (-CH_{2}-, methylene) necessary to hook these carbon rings
together may be obtained from other substances than the aldehydes,
for instance from the amines, or ammonia derivatives. Three chemists,
L.V. Kedman, A.J. Weith and F.P. Broek, working in 1910 on the
Industrial Fellowships of the late Robert Kennedy Duncan at the
University of Kansas, developed a process using formin instead
of formaldehyde. Formin--or, if you insist upon its full name,
hexa-methylene-tetramine--is a sugar-like substance with a fish-like
smell. This mixed with crystallized carbolic acid and slightly warmed
melts to a golden liquid that sets on pouring into molds. It is still
plastic and can be bent into any desired shape, but on further heating
it becomes hard without the need of pressure. Ammonia is given off in
this process instead of water which is the by-product in the case of
formaldehyde. The product is similar to bakelite, exactly how similar is
a question that the courts will have to decide. The inventors threatened
to call it Phenyl-endeka-saligeno-saligenin, but, rightly fearing that
this would interfere with its salability, they have named it "redmanol."
A phenolic condensation product closely related to bakelite and redmanol
is condensite, the invention of Jonas Walter Aylesworth. Aylesworth was
trained in what he referred to as "the greatest university of the world,
the Edison laboratory." He entered this university at the age of
nineteen at a salary of $3 a week, but Edison soon found that he had in
his new boy an assistant who could stand being shut up in the laboratory
working day and night as long as he could. After nine years of close
association with Edison he set up a little laboratory in his own back
yard to work out new plastics. He found that by acting on
naphthalene--the moth-ball stuff--with chlorine he got a series of
useful products called "halowaxes." The lower chlorinated products are
oils, which may be used for impregnating paper or soft wood, making it
non-inflammable and impregnable to water. If four atoms of chlorine
enter the naphthalene molecule the product is a hard wax that rings like
a metal.
Condensite is anhydrous and infusible, and like its rivals finds its
chief employment in the insulation parts of electrical apparatus. The
records of the Edison phonograph are made of it. So are the buttons of
our blue-jackets. The Government at the outbreak of the war ordered
40,000 goggles in condensite frames to protect the eyes of our gunners
from the glare and acid fumes.
The various synthetics played an important part in the war. According to
an ancient military pun the endurance of soldiers depends upon the
strength of their soles. The new compound rubber soles were found useful
in our army and the Germans attribute their success in making a little
leather go a long way during the late war to the use of a new synthetic
tanning material known as "neradol." There are various forms of this.
Some are phenolic condensation products of formaldehyde like those we
have been considering, but some use coal-tar compounds having no phenol
groups, such as naphthalene sulfonic acid. These are now being made in
England under such names as "paradol," "cresyntan" and "syntan." They
have the advantage of the natural tannins such as bark in that they are
of known strength and can be varied to suit.
This very grasping compound, formaldehyde, will attack almost anything,
even molecules many times its size. Gelatinous and albuminous substances
of all sorts are solidified by it. Glue, skimmed milk, blood, eggs,
yeast, brewer's slops, may by this magic agent be rescued from waste and
reappear in our buttons, hairpins, roofing, phonographs, shoes or
shoe-polish. The French have made great use of casein hardened by
formaldehyde into what is known as "galalith" (i.e., milkstone). This is
harder than celluloid and non-inflammable, but has the disadvantages of
being more brittle and of absorbing moisture. A mixture of casein and
celluloid has something of the merits of both.
The Japanese, as we should expect, are using the juice of the soy bean,
familiar as a condiment to all who patronize chop-sueys or use
Worcestershire sauce. The soy glucine coagulated by formalin gives a
plastic said to be better and cheaper than celluloid. Its inventor, S.
Sato, of Sendai University, has named it, according to American
precedent, "Satolite," and has organized a million-dollar Satolite
Company at Mukojima.
The algin extracted from the Pacific kelp can be used as a rubber
surrogate for water-proofing cloth. When combined with heavier alkaline
bases it forms a tough and elastic substance that can be rolled into
transparent sheets like celluloid or turned into buttons and knife
handles.
In Australia when the war shut off the supply of tin the Government
commission appointed to devise means of preserving fruits recommended
the use of cardboard containers varnished with "magramite." This is a
name the Australians coined for synthetic resin made from phenol and
formaldehyde like bakelite. Magramite dissolved in alcohol is painted on
the cardboard cans and when these are stoved the coating becomes
insoluble.
Tarasoff has made a series of condensation products from phenol and
formaldehyde with the addition of sulfonated oils. These are formed by
the action of sulfuric acid on coconut, castor, cottonseed or mineral
oils. The products of this combination are white plastics, opaque,
insoluble and infusible.
Since I am here chiefly concerned with "Creative Chemistry," that is,
with the art of making substances not found in nature, I have not spoken
of shellac, asphaltum, rosin, ozocerite and the innumerable gums, resins
and waxes, animal, mineral and vegetable, that are used either by
themselves or in combination with the synthetics. What particular "dope"
or "mud" is used to coat a canvas or form a telephone receiver is often
hard to find out. The manufacturer finds secrecy safer than the patent
office and the chemist of a rival establishment is apt to be baffled in
his attempt to analyze and imitate. But we of the outside world are not
concerned with this, though we are interested in the manifold
applications of these new materials.
There seems to be no limit to these compounds and every week the
journals report new processes and patents. But we must not allow the new
ones to crowd out the remembrance of the oldest and most famous of the
synthetic plasters, hard rubber, to which a separate chapter must be
devoted.
VIII
THE RACE FOR RUBBER
There is one law that regulates all animate and inanimate things. It is
formulated in various ways, for instance:
Running down a hill is easy. In Latin it reads, _facilis descensus
Averni._ Herbert Spencer calls it the dissolution of definite coherent
heterogeneity into indefinite incoherent homogeneity. Mother Goose
expresses it in the fable of Humpty Dumpty, and the business man
extracts the moral as, "You can't unscramble an egg." The theologian
calls it the dogma of natural depravity. The physicist calls it the
second law of thermodynamics. Clausius formulates it as "The entropy of
the world tends toward a maximum." It is easier to smash up than to
build up. Children find that this is true of their toys; the Bolsheviki
have found that it is true of a civilization. So, too, the chemist knows
analysis is easier than synthesis and that creative chemistry is the
highest branch of his art.
This explains why chemists discovered how to take rubber apart over
sixty years before they could find out how to put it together. The first
is easy. Just put some raw rubber into a retort and heat it. If you can
stand the odor you will observe the caoutchouc decomposing and a
benzine-like liquid distilling over. This is called "isoprene." Any
Freshman chemist could write the reaction for this operation. It is
simply
C_{10}H_{16} --> 2C_{5}H_{8}
caoutchouc isoprene
That is, one molecule of the gum splits up into two molecules of the
liquid. It is just as easy to write the reaction in the reverse
directions, as 2 isoprene--> 1 caoutchouc, but nobody could make it go
in that direction. Yet it could be done. It had been done. But the man
who did it did not know how he did it and could not do it again.
Professor Tilden in May, 1892, read a paper before the Birmingham
Philosophical Society in which he said:
I was surprised a few weeks ago at finding the contents of the
bottles containing isoprene from turpentine entirely changed in
appearance. In place of a limpid, colorless liquid the bottles
contained a dense syrup in which were floating several large
masses of a yellowish color. Upon examination this turned out
to be India rubber.
But neither Professor Tilden nor any one else could repeat this
accidental metamorphosis. It was tantalizing, for the world was willing
to pay $2,000,000,000 a year for rubber and the forests of the Amazon
and Congo were failing to meet the demand. A large share of these
millions would have gone to any chemist who could find out how to make
synthetic rubber and make it cheaply enough. With such a reward of fame
and fortune the competition among chemists was intense. It took the form
of an international contest in which England and Germany were neck and
neck.
[Illustration: Courtesy of the "India Rubber World."
What goes into rubber and what is made out of it]
The English, who had been beaten by the Germans in the dye business
where they had the start, were determined not to lose in this. Prof.
W.H. Perkin, of Manchester University, was one of the most eager, for he
was inspired by a personal grudge against the Germans as well as by
patriotism and scientific zeal. It was his father who had, fifty years
before, discovered mauve, the first of the anilin dyes, but England
could not hold the business and its rich rewards went over to Germany.
So in 1909 a corps of chemists set to work under Professor Perkin in the
Manchester laboratories to solve the problem of synthetic rubber. What
reagent could be found that would reverse the reaction and convert the
liquid isoprene into the solid rubber? It was discovered, by accident,
we may say, but it should be understood that such advantageous accidents
happen only to those who are working for them and know how to utilize
them. In July, 1910, Dr. Matthews, who had charge of the research, set
some isoprene to drying over metallic sodium, a common laboratory method
of freeing a liquid from the last traces of water. In September he found
that the flask was filled with a solid mass of real rubber instead of
the volatile colorless liquid he had put into it.
Twenty years before the discovery would have been useless, for sodium
was then a rare and costly metal, a little of it in a sealed glass tube
being passed around the chemistry class once a year as a curiosity, or a
tiny bit cut off and dropped in water to see what a fuss it made. But
nowadays metallic sodium is cheaply produced by the aid of electricity.
The difficulty lay rather in the cost of the raw material, isoprene. In
industrial chemistry it is not sufficient that a thing can be made; it
must be made to pay. Isoprene could be obtained from turpentine, but
this was too expensive and limited in supply. It would merely mean the
destruction of pine forests instead of rubber forests. Starch was
finally decided upon as the best material, since this can be obtained
for about a cent a pound from potatoes, corn and many other sources.
Here, however, the chemist came to the end of his rope and had to call
the bacteriologist to his aid. The splitting of the starch molecule is
too big a job for man; only the lower organisms, the yeast plant, for
example, know enough to do that. Owing perhaps to the _entente cordiale_
a French biologist was called into the combination, Professor Fernbach,
of the Pasteur Institute, and after eighteen months' hard work he
discovered a process of fermentation by which a large amount of fusel
oil can be obtained from any starchy stuff. Hitherto the aim in
fermentation and distillation had been to obtain as small a proportion
of fusel as possible, for fusel oil is a mixture of the heavier
alcohols, all of them more poisonous and malodorous than common alcohol.
But here, as has often happened in the history of industrial chemistry,
the by-product turned out to be more valuable than the product. From
fusel oil by the use of chlorine isoprene can be prepared, so the chain
was complete.
But meanwhile the Germans had been making equal progress. In 1905 Prof.
Karl Harries, of Berlin, found out the name of the caoutchouc molecule.
This discovery was to the chemists what the architect's plan of a house
is to the builder. They knew then what they were trying to construct
and could go about their task intelligently.
Mark Twain said that he could understand something about how astronomers
could measure the distance of the planets, calculate their weights and
so forth, but he never could see how they could find out their names
even with the largest telescopes. This is a joke in astronomy but it
is not in chemistry. For when the chemist finds out the structure
of a compound he gives it a name which means that. The stuff came
to be called "caoutchouc," because that was the way the Spaniards
of Columbus's time caught the Indian word "cahuchu." When
Dr. Priestley called it "India rubber" he told merely where it
came from and what it was good for. But when Harries named it
"1-5-dimethyl-cyclo-octadien-1-5" any chemist could draw a picture of it
and give a guess as to how it could be made. Even a person without any
knowledge of chemistry can get the main point of it by merely looking at
this diagram:
C C C---C
|| || || |
C--C C C--C C
| | --> | |
C C--C C C--C
|| || | ||
C C C---C
[Illustration: isoprene _turns into_ caoutchouc]
I have dropped the 16 H's or hydrogen atoms of the formula for
simplicity's sake. They simply hook on wherever they can. You will see
that the isoprene consists of a chain of four carbon atoms (represented
by the C's) with an extra carbon on the side. In the transformation of
this colorless liquid into soft rubber two of the double linkages break
and so permit the two chains of 4 C's to unite to form one ring of
eight. If you have ever played ring-around-a-rosy you will get the idea.
In Chapter IV I explained that the anilin dyes are built up upon the
benzene ring of six carbon atoms. The rubber ring consists of eight at
least and probably more. Any substance containing that peculiar carbon
chain with two double links C=C-C=C can double up--polymerize, the
chemist calls it--into a rubber-like substance. So we may have many
kinds of rubber, some of which may prove to be more useful than that
which happens to be found in nature.
With the structural formula of Harries as a clue chemists all over the
world plunged into the problem with renewed hope. The famous Bayer dye
works at Elberfeld took it up and there in August, 1909, Dr. Fritz
Hofmann worked out a process for the converting of pure isoprene into
rubber by heat. Then in 1910 Harries happened upon the same sodium
reaction as Matthews, but when he came to get it patented he found that
the Englishman had beaten him to the patent office by a few weeks.
This Anglo-German rivalry came to a dramatic climax in 1912 at the great
hall of the College of the City of New York when Dr. Carl Duisberg, of
the Elberfeld factory, delivered an address on the latest achievements
of the chemical industry before the Eighth--and the last for a long
time--International Congress of Applied Chemistry. Duisberg insisted
upon talking in German, although more of his auditors would have
understood him in English. He laid full emphasis upon German
achievements and cast doubt upon the claim of "the Englishman Tilden" to
have prepared artificial rubber in the eighties. Perkin, of Manchester,
confronted him with his new process for making rubber from potatoes, but
Duisberg countered by proudly displaying two automobile tires made of
synthetic rubber with which he had made a thousand-mile run.
The intense antagonism between the British and German chemists at this
congress was felt by all present, but we did not foresee that in two
years from that date they would be engaged in manufacturing poison gas
to fire at one another. It was, however, realized that more was at stake
than personal reputation and national prestige. Under pressure of the
new demand for automobiles the price of rubber jumped from $1.25 to $3 a
pound in 1910, and millions had been invested in plantations. If
Professor Perkin was right when he told the congress that by his process
rubber could be made for less than 25 cents a pound it meant that these
plantations would go the way of the indigo plantations when the Germans
succeeded in making artificial indigo. If Dr. Duisberg was right when he
told the congress that synthetic rubber would "certainly appear on the
market in a very short time," it meant that Germany in war or peace
would become independent of Brazil in the matter of rubber as she had
become independent of Chile in the matter of nitrates.
As it turned out both scientists were too sanguine. Synthetic rubber has
not proved capable of displacing natural rubber by underbidding it nor
even of replacing natural rubber when this is shut out. When Germany
was blockaded and the success of her armies depended on rubber, price
was no object. Three Danish sailors who were caught by United States
officials trying to smuggle dental rubber into Germany confessed that
they had been selling it there for gas masks at $73 a pound. The German
gas masks in the latter part of the war were made without rubber and
were frail and leaky. They could not have withstood the new gases which
American chemists were preparing on an unprecedented scale. Every scrap
of old rubber in Germany was saved and worked over and over and diluted
with fillers and surrogates to the limit of elasticity. Spring tires
were substituted for pneumatics. So it is evident that the supply of
synthetic rubber could not have been adequate or satisfactory. Neither,
on the other hand, have the British made a success of the Perkin
process, although they spent $200,000 on it in the first two years. But,
of course, there was not the same necessity for it as in the case of
Germany, for England had practically a monopoly of the world's supply of
natural rubber either through owning plantations or controlling
shipping. If rubber could not be manufactured profitably in Germany when
the demand was imperative and price no consideration it can hardly be
expected to compete with the natural under peace conditions.
The problem of synthetic rubber has then been solved scientifically but
not industrially. It can be made but cannot be made to pay. The
difficulty is to find a cheap enough material to start with. We can make
rubber out of potatoes--but potatoes have other uses. It would require
more land and more valuable land to raise the potatoes than to raise the
rubber. We can get isoprene by the distillation of turpentine--but why
not bleed a rubber tree as well as a pine tree? Turpentine is neither
cheap nor abundant enough. Any kind of wood, sawdust for instance, can
be utilized by converting the cellulose over into sugar and fermenting
this to alcohol, but the process is not likely to prove profitable.
Petroleum when cracked up to make gasoline gives isoprene or other
double-bond compounds that go over into some form of rubber.
But the most interesting and most promising of all is the complete
inorganic synthesis that dispenses with the aid of vegetation and starts
with coal and lime. These heated together in the electric furnace form
calcium carbide and this, as every automobilist knows, gives acetylene
by contact with water. From this gas isoprene can be made and the
isoprene converted into rubber by sodium, or acid or alkali or simple
heating. Acetone, which is also made from acetylene, can be converted
directly into rubber by fuming sulfuric acid. This seems to have been
the process chiefly used by the Germans during the war. Several carbide
factories were devoted to it. But the intermediate and by-products of
the process, such as alcohol, acetic acid and acetone, were in as much
demand for war purposes as rubber. The Germans made some rubber from
pitch imported from Sweden. They also found a useful substitute in
aluminum naphthenate made from Baku petroleum, for it is elastic and
plastic and can be vulcanized.
So although rubber can be made in many different ways it is not
profitable to make it in any of them. We have to rely still upon the
natural product, but we can greatly improve upon the way nature produces
it. When the call came for more rubber for the electrical and automobile
industries the first attempt to increase the supply was to put pressure
upon the natives to bring in more of the latex. As a consequence the
trees were bled to death and sometimes also the natives. The Belgian
atrocities in the Congo shocked the civilized world and at Putumayo on
the upper Amazon the same cause produced the same horrible effects. But
no matter what cruelty was practiced the tropical forests could not be
made to yield a sufficient increase, so the cultivation of the rubber
was begun by far-sighted men in Dutch Java, Sumatra and Borneo and in
British Malaya and Ceylon.
Brazil, feeling secure in the possession of a natural monopoly, made no
effort to compete with these parvenus. It cost about as much to gather
rubber from the Amazon forests as it did to raise it on a Malay
plantation, that is, 25 cents a pound. The Brazilian Government clapped
on another 25 cents export duty and spent the money lavishly. In 1911
the treasury of Para took in $2,000,000 from the rubber tax and a good
share of the money was spent on a magnificent new theater at Manaos--not
on setting out rubber trees. The result of this rivalry between the
collector and the cultivator is shown by the fact that in the decade
1907-1917 the world's output of plantation rubber increased from 1000 to
204,000 tons, while the output of wild rubber decreased from 68,000 to
53,000. Besides this the plantation rubber is a cleaner and more even
product, carefully coagulated by acetic acid instead of being smoked
over a forest fire. It comes in pale yellow sheets instead of big black
balls loaded with the dirt or sticks and stones that the honest Indian
sometimes adds to make a bigger lump. What's better, the man who milks
the rubber trees on a plantation may live at home where he can be
decently looked after. The agriculturist and the chemist may do what the
philanthropist and statesman could not accomplish: put an end to the
cruelties involved in the international struggle for "black gold."
The United States uses three-fourths of the world's rubber output and
grows none of it. What is the use of tropical possessions if we do not
make use of them? The Philippines could grow all our rubber and keep a
$300,000,000 business under our flag. Santo Domingo, where rubber was
first discovered, is now under our supervision and could be enriched by
the industry. The Guianas, where the rubber tree was first studied,
might be purchased. It is chiefly for lack of a definite colonial policy
that our rubber industry, by far the largest in the world, has to be
dependent upon foreign sources for all its raw materials. Because the
Philippines are likely to be cast off at any moment, American
manufacturers are placing their plantations in the Dutch or British
possessions. The Goodyear Company has secured a concession of 20,000
acres near Medan in Dutch Sumatra.
While the United States is planning to relinquish its Pacific
possessions the British have more than doubled their holdings in New
Guinea by the acquisition of Kaiser Wilhelm's Land, good rubber
country. The British Malay States in 1917 exported over $118,000,000
worth of plantation-grown rubber and could have sold more if shipping
had not been short and production restricted. Fully 90 per cent. of the
cultivated rubber is now grown in British colonies or on British
plantations in the Dutch East Indies. To protect this monopoly an act
has been passed preventing foreigners from buying more land in the Malay
Peninsula. The Japanese have acquired there 50,000 acres, on which they
are growing more than a million dollars' worth of rubber a year. The
British _Tropical Life_ says of the American invasion: "As America is so
extremely wealthy Uncle Sam can well afford to continue to buy our
rubber as he has been doing instead of coming in to produce rubber to
reduce his competition as a buyer in the world's market." The Malaya
estates calculate to pay a dividend of 20 per cent. on the investment
with rubber selling at 30 cents a pound and every two cents additional
on the price brings a further 3-1/2 per cent. dividend. The output is
restricted by the Rubber Growers' Association so as to keep the price up
to 50-70 cents. When the plantations first came into bearing in 1910
rubber was bringing nearly $3 a pound, and since it can be produced at
less than 30 cents a pound we can imagine the profits of the early
birds.
The fact that the world's rubber trade was in the control of Great
Britain caused America great anxiety and financial loss in the early
part of the war when the British Government, suspecting--not without
reason--that some American rubber goods were getting into Germany
through neutral nations, suddenly shut off our supply. This threatened
to kill the fourth largest of our industries and it was only by the
submission of American rubber dealers to the closest supervision and
restriction by the British authorities that they were allowed to
continue their business. Sir Francis Hopwood, in laying down these
regulations, gave emphatic warning "that in case any manufacturer,
importer or dealer came under suspicion his permits should be
immediately revoked. Reinstatement will be slow and difficult. The
British Government will cancel first and investigate afterward." Of
course the British had a right to say under what conditions they should
sell their rubber and we cannot blame them for taking such precautions
to prevent its getting to their enemies, but it placed the United States
in a humiliating position and if we had not been in sympathy with their
side it would have aroused more resentment than it did. But it made
evident the desirability of having at least part of our supply under our
own control and, if possible, within our own country. Rubber is not rare
in nature, for it is contained in almost every milky juice. Every
country boy knows that he can get a self-feeding mucilage brush by
cutting off a milkweed stalk. The only native source so far utilized is
the guayule, which grows wild on the deserts of the Mexican and the
American border. The plant was discovered in 1852 by Dr. J.M. Bigelow
near Escondido Creek, Texas. Professor Asa Gray described it and named
it Parthenium argentatum, or the silver Pallas. When chopped up and
macerated guayule gives a satisfactory quality of caoutchouc in
profitable amounts. In 1911 seven thousand tons of guayule were
imported from Mexico; in 1917 only seventeen hundred tons. Why this
falling off? Because the eager exploiters had killed the goose that laid
the golden egg, or in plain language, pulled up the plant by the roots.
Now guayule is being cultivated and is reaped instead of being uprooted.
Experiments at the Tucson laboratory have recently removed the
difficulty of getting the seed to germinate under cultivation. This
seems the most promising of the home-grown plants and, until artificial
rubber can be made profitable, gives us the only chance of being in part
independent of oversea supply.
There are various other gums found in nature that can for some purposes
be substituted for caoutchouc. Gutta percha, for instance, is pliable
and tough though not very elastic. It becomes plastic by heat so it can
be molded, but unlike rubber it cannot be hardened by heating with
sulfur. A lump of gutta percha was brought from Java in 1766 and placed
in a British museum, where it lay for nearly a hundred years before it
occurred to anybody to do anything with it except to look at it. But a
German electrician, Siemens, discovered in 1847 that gutta percha was
valuable for insulating telegraph lines and it found extensive
employment in submarine cables as well as for golf balls, and the like.
Balata, which is found in the forests of the Guianas, is between gutta
percha and rubber, not so good for insulation but useful for shoe soles
and machine belts. The bark of the tree is so thick that the latex does
not run off like caoutchouc when the bark is cut. So the bark has to be
cut off and squeezed in hand presses. Formerly this meant cutting down
the tree, but now alternate strips of the bark are cut off and squeezed
so the tree continues to live.
When Columbus discovered Santo Domingo he found the natives playing with
balls made from the gum of the caoutchouc tree. The soldiers of Pizarro,
when they conquered Inca-Land, adopted the Peruvian custom of smearing
caoutchouc over their coats to keep out the rain. A French scientist, M.
de la Condamine, who went to South America to measure the earth, came
back in 1745 with some specimens of caoutchouc from Para as well as
quinine from Peru. The vessel on which he returned, the brig _Minerva_,
had a narrow escape from capture by an English cruiser, for Great
Britain was jealous of any trespassing on her American sphere of
influence. The Old World need not have waited for the discovery of the
New, for the rubber tree grows wild in Annam as well as Brazil, but none
of the Asiatics seems to have discovered any of the many uses of the
juice that exudes from breaks in the bark.
The first practical use that was made of it gave it the name that has
stuck to it in English ever since. Magellan announced in 1772 that it
was good to remove pencil marks. A lump of it was sent over from France
to Priestley, the clergyman chemist who discovered oxygen and was mobbed
out of Manchester for being a republican and took refuge in
Pennsylvania. He cut the lump into little cubes and gave them to his
friends to eradicate their mistakes in writing or figuring. Then they
asked him what the queer things were and he said that they were "India
rubbers."
[Illustration: FOREST RUBBER
Compare this tropical tangle and gnarled trunk with the straight tree
and cleared ground of the plantation. At the foot of the trunk are cups
collecting rubber juice.]
[Illustration: PLANTATION RUBBER
This spiral cut draws off the milk as completely and quickly as possible
without harming the tree. The man is pulling off a strip of coagulated
rubber that clogs it.]
[Illustration: IN MAKING GARDEN HOSE THE RUBBER IS FORMED INTO A TUBE
BY THE MACHINE ON THE RIGHT AND COILED ON THE TABLE TO THE LEFT]
The Peruvian natives had used caoutchouc for water-proof clothing,
shoes, bottles and syringes, but Europe was slow to take it up, for the
stuff was too sticky and smelled too bad in hot weather to become
fashionable in fastidious circles. In 1825 Mackintosh made his name
immortal by putting a layer of rubber between two cloths.
A German chemist, Ludersdorf, discovered in 1832 that the gum could be
hardened by treating it with sulfur dissolved in turpentine. But it was
left to a Yankee inventor, Charles Goodyear, of Connecticut, to work out
a practical solution of the problem. A friend of his, Hayward, told him
that it had been revealed to him in a dream that sulfur would harden
rubber, but unfortunately the angel or defunct chemist who inspired the
vision failed to reveal the details of the process. So Hayward sold out
his dream to Goodyear, who spent all his own money and all he could
borrow from his friends trying to convert it into a reality. He worked
for ten years on the problem before the "lucky accident" came to him.
One day in 1839 he happened to drop on the hot stove of the kitchen that
he used as a laboratory a mixture of caoutchouc and sulfur. To his
surprise he saw the two substances fuse together into something new.
Instead of the soft, tacky gum and the yellow, brittle brimstone he had
the tough, stable, elastic solid that has done so much since to make our
footing and wheeling safe, swift and noiseless. The gumshoes or galoshes
that he was then enabled to make still go by the name of "rubbers" in
this country, although we do not use them for pencil erasers.
Goodyear found that he could vary this "vulcanized rubber" at will. By
adding a little more sulfur he got a hard substance which, however,
could be softened by heat so as to be molded into any form wanted. Out
of this "hard rubber" "vulcanite" or "ebonite" were made combs,
hairpins, penholders and the like, and it has not yet been superseded
for some purposes by any of its recent rivals, the synthetic resins.
The new form of rubber made by the Germans, methyl rubber, is said to be
a superior substitute for the hard variety but not satisfactory for the
soft. The electrical resistance of the synthetic product is 20 per cent,
higher than the natural, so it is excellent for insulation, but it is
inferior in elasticity. In the latter part of the war the methyl rubber
was manufactured at the rate of 165 tons a month.
The first pneumatic tires, known then as "patent aerial wheels," were
invented by Robert William Thomson of London in 1846. On the following
year a carriage equipped with them was seen in the streets of New York
City. But the pneumatic tire did not come into use until after 1888,
when an Irish horse-doctor, John Boyd Dunlop, of Belfast, tied a rubber
tube around the wheels of his little son's velocipede. Within seven
years after that a $25,000,000 corporation was manufacturing Dunlop
tires. Later America took the lead in this business. In 1913 the United
States exported $3,000,000 worth of tires and tubes. In 1917 the
American exports rose to $13,000,000, not counting what went to the
Allies. The number of pneumatic tires sold in 1917 is estimated at
18,000,000, which at an average cost of $25 would amount to
$450,000,000.
No matter how much synthetic rubber may be manufactured or how many
rubber trees are set out there is no danger of glutting the market, for
as the price falls the uses of rubber become more numerous. One can
think of a thousand ways in which rubber could be used if it were only
cheap enough. In the form of pads and springs and tires it would do much
to render traffic noiseless. Even the elevated railroad and the subway
might be opened to conversation, and the city made habitable for mild
voiced and gentle folk. It would make one's step sure, noiseless and
springy, whether it was used individualistically as rubber heels or
collectivistically as carpeting and paving. In roofing and siding and
paint it would make our buildings warmer and more durable. It would
reduce the cost and permit the extension of electrical appliances of
almost all kinds. In short, there is hardly any other material whose
abundance would contribute more to our comfort and convenience. Noise is
an automatic alarm indicating lost motion and wasted energy. Silence is
economy and resiliency is superior to resistance. A gumshoe outlasts a
hobnailed sole and a rubber tube full of air is better than a steel
tire.
IX
THE RIVAL SUGARS
The ancient Greeks, being an inquisitive and acquisitive people, were
fond of collecting tales of strange lands. They did not care much
whether the stories were true or not so long as they were interesting.
Among the marvels that the Greeks heard from the Far East two of the
strangest were that in India there were plants that bore wool without
sheep and reeds that bore honey without bees. These incredible tales
turned out to be true and in the course of time Europe began to get a
little calico from Calicut and a kind of edible gravel that the Arabs
who brought it called "sukkar." But of course only kings and queens
could afford to dress in calico and have sugar prescribed for them when
they were sick.
Fortunately, however, in the course of time the Arabs invaded Spain and
forced upon the unwilling inhabitants of Europe such instrumentalities
of higher civilization as arithmetic and algebra, soap and sugar. Later
the Spaniards by an act of equally unwarranted and beneficent aggression
carried the sugar cane to the Caribbean, where it thrived amazingly. The
West Indies then became a rival of the East Indies as a treasure-house
of tropical wealth and for several centuries the Spanish, Portuguese,
Dutch, English, Danes and French fought like wildcats to gain possession
of this little nest of islands and the routes leading thereunto.
The English finally overcame all these enemies, whether they fought her
singly or combined. Great Britain became mistress of the seas and took
such Caribbean lands as she wanted. But in the end her continental foes
came out ahead, for they rendered her victory valueless. They were
defeated in geography but they won in chemistry. Canning boasted that
"the New World had been called into existence to redress the balance of
the Old." Napoleon might have boasted that he had called in the sugar
beet to balance the sugar cane. France was then, as Germany was a
century later, threatening to dominate the world. England, then as in
the Great War, shut off from the seas the shipping of the aggressive
power. France then, like Germany later, felt most keenly the lack of
tropical products, chief among which, then but not in the recent crisis,
was sugar. The cause of this vital change is that in 1747 Marggraf, a
Berlin chemist, discovered that it was possible to extract sugar from
beets. There was only a little sugar in the beet root then, some six per
cent., and what he got out was dirty and bitter. One of his pupils in
1801 set up a beet sugar factory near Breslau under the patronage of the
King of Prussia, but the industry was not a success until Napoleon took
it up and in 1810 offered a prize of a million francs for a practical
process. How the French did make fun of him for this crazy notion! In a
comic paper of that day you will find a cartoon of Napoleon in the
nursery beside the cradle of his son and heir, the King of Rome--known
to the readers of Rostand as l'Aiglon. The Emperor is squeezing the
juice of a beet into his coffee and the nurse has put a beet into the
mouth of the infant King, saying: "Suck, dear, suck. Your father says
it's sugar."
In like manner did the wits ridicule Franklin for fooling with
electricity, Rumford for trying to improve chimneys, Parmentier for
thinking potatoes were fit to eat, and Jefferson for believing that
something might be made of the country west of the Mississippi. In all
ages ridicule has been the chief weapon of conservatism. If you want to
know what line human progress will take in the future read the funny
papers of today and see what they are fighting. The satire of every
century from Aristophanes to the latest vaudeville has been directed
against those who are trying to make the world wiser or better, against
the teacher and the preacher, the scientist and the reformer.
In spite of the ridicule showered upon it the despised beet year by year
gained in sweetness of heart. The percentage of sugar rose from six to
eighteen and by improved methods of extraction became finally as pure
and palatable as the sugar of the cane. An acre of German beets produces
more sugar than an acre of Louisiana cane. Continental Europe waxed
wealthy while the British West Indies sank into decay. As the beets of
Europe became sweeter the population of the islands became blacker.
Before the war England was paying out $125,000,000 for sugar, and more
than two-thirds of this money was going to Germany and Austria-Hungary.
Fostered by scientific study, protected by tariff duties, and stimulated
by export bounties, the beet sugar industry became one of the financial
forces of the world. The English at home, especially the
marmalade-makers, at first rejoiced at the idea of getting sugar for
less than cost at the expense of her continental rivals. But the
suffering colonies took another view of the situation. In 1888 a
conference of the powers called at London agreed to stop competing by
the pernicious practice of export bounties, but France and the United
States refused to enter, so the agreement fell through. Another
conference ten years later likewise failed, but when the parvenu beet
sugar ventured to invade the historic home of the cane the limit of
toleration had been reached. The Council of India put on countervailing
duties to protect their homegrown cane from the bounty-fed beet. This
forced the calling of a convention at Brussels in 1903 "to equalize the
conditions of competition between beet sugar and cane sugar of the
various countries," at which the powers agreed to a mutual suppression
of bounties. Beet sugar then divided the world's market equally with
cane sugar and the two rivals stayed substantially neck and neck until
the Great War came. This shut out from England the product of Germany,
Austria-Hungary, Belgium, northern France and Russia and took the
farmers from their fields. The battle lines of the Central Powers
enclosed the land which used to grow a third of the world's supply of
sugar. In 1913 the beet and the cane each supplied about nine million
tons of sugar. In 1917 the output of cane sugar was 11,200,000 and of
beet sugar 5,300,000 tons. Consequently the Old World had to draw upon
the New. Cuba, on which the United States used to depend for half its
sugar supply, sent over 700,000 tons of raw sugar to England in 1916.
The United States sent as much more refined sugar. The lack of shipping
interfered with our getting sugar from our tropical dependencies,
Hawaii, Porto Rico and the Philippines. The homegrown beets give us only
a fifth and the cane of Louisiana and Texas only a fifteenth of the
sugar we need. As a result we were obliged to file a claim in advance to
get a pound of sugar from the corner grocery and then we were apt to be
put off with rock candy, muscovado or honey. Lemon drops proved useful
for Russian tea and the "long sweetening" of our forefathers came again
into vogue in the form of various syrups. The United States was
accustomed to consume almost a fifth of all the sugar produced in the
world--and then we could not get it.
[Illustration: MAP SHOWING LOCATION OF EUROPEAN BEET SUGAR
FACTORIES--ALSO BATTLE LINES AT CLOSE OF 1918 ESTIMATED THAT ONE-THIRD
OF WORLDS PRODUCTION BEFORE THE WAR WAS PRODUCED WITHIN BATTLE LINES
Courtesy American Sugar Refining Co.]
The shortage made us realize how dependent we have become upon sugar.
Yet it was, as we have seen, practically unknown to the ancients and
only within the present generation has it become an essential factor in
our diet. As soon as the chemist made it possible to produce sugar at a
reasonable price all nations began to buy it in proportion to their
means. Americans, as the wealthiest people in the world, ate the most,
ninety pounds a year on the average for every man, woman and child. In
other words we ate our weight of sugar every year. The English consumed
nearly as much as the Americans; the French and Germans about half as
much; the Balkan peoples less than ten pounds per annum; and the African
savages none.
[Illustration: How the sugar beet has gained enormously in sugar content
under chemical control]
Pure white sugar is the first and greatest contribution of chemistry to
the world's dietary. It is unique in being a single definite chemical
compound, sucrose, C_{12}H_{22}O_{11}. All natural nutriments are more
or less complex mixtures. Many of them, like wheat or milk or fruit,
contain in various proportions all of the three factors of foods, the
fats, the proteids and the carbohydrates, as well as water and the
minerals and other ingredients necessary to life. But sugar is a simple
substance, like water or salt, and like them is incapable of sustaining
life alone, although unlike them it is nutritious. In fact, except the
fats there is no more nutritious food than sugar, pound for pound, for
it contains no water and no waste. It is therefore the quickest and
usually the cheapest means of supplying bodily energy. But as may be
seen from its formula as given above it contains only three elements,
carbon, hydrogen and oxygen, and omits nitrogen and other elements
necessary to the body. An engine requires not only coal but also
lubricating oil, water and bits of steel and brass to keep it in repair.
But as a source of the energy needed in our strenuous life sugar has no
equal and only one rival, alcohol. Alcohol is the offspring of sugar, a
degenerate descendant that retains but few of the good qualities of its
sire and has acquired some evil traits of its own. Alcohol, like sugar,
may serve to furnish the energy of a steam engine or a human body. Used
as a fuel alcohol has certain advantages, but used as a food it has the
disqualification of deranging the bodily mechanism. Even a little
alcohol will impair the accuracy and speed of thought and action, while
a large quantity, as we all know from observation if not experience,
will produce temporary incapacitation.
When man feeds on sugar he splits it up by the aid of air into water and
carbon dioxide in this fashion:
C_{12}H_{22}O_{11} + 12O_{2} --> 11H_{2}O + 12CO_{2}
cane sugar oxygen water carbon dioxide
When sugar is burned the reaction is just the same.
But when the yeast plant feeds on sugar it carries the process only part
way and instead of water the product is alcohol, a very different thing,
so they say who have tried both as beverages. The yeast or fermentation
reaction is this:
C_{12}H_{22}O_{11} + H_{2}O --> 4C_{2}H_{6}O + 4CO_{2}
cane sugar water alcohol carbon dioxide
Alcohol then is the first product of the decomposition of sugar, a
dangerous half-way house. The twin product, carbon dioxide or carbonic
acid, is a gas of slightly sour taste which gives an attractive tang and
effervescence to the beer, wine, cider or champagne. That is to say, one
of these twins is a pestilential fellow and the other is decidedly
agreeable. Yet for several thousand years mankind took to the first and
let the second for the most part escape into the air. But when the
chemist appeared on the scene he discovered a way of separating the two
and bottling the harmless one for those who prefer it. An increasing
number of people were found to prefer it, so the American soda-water
fountain is gradually driving Demon Rum out of the civilized world. The
brewer nowadays caters to two classes of customers. He bottles up the
beer with the alcohol and a little carbonic acid in it for the saloon
and he catches the rest of the carbonic acid that he used to waste and
sells it to the drug stores for soda-water or uses it to charge some
non-alcoholic beer of his own.
This catering to rival trades is not an uncommon thing with the chemist.
As we have seen, the synthetic perfumes are used to improve the natural
perfumes. Cottonseed is separated into oil and meal; the oil going to
make margarin and the meal going to feed the cows that produce butter.
Some people have been drinking coffee, although they do not like the
taste of it, because they want the stimulating effect of its alkaloid,
caffein. Other people liked the warmth and flavor of coffee but find
that caffein does not agree with them. Formerly one had to take the
coffee whole or let it alone. Now one can have his choice, for the
caffein is extracted for use in certain popular cold drinks and the rest
of the bean sold as caffein-free coffee.
Most of the "soft drinks" that are now gradually displacing the hard
ones consist of sugar, water and carbonic acid, with various flavors,
chiefly the esters of the fatty and aromatic acids, such as I described
in a previous chapter. These are still usually made from fruits and
spices and in some cases the law or public opinion requires this, but
eventually, I presume, the synthetic flavors will displace the natural
and then we shall get rid of such extraneous and indigestible matter as
seeds, skins and bark. Suppose the world had always been used to
synthetic and hence seedless figs, strawberries and blackberries.
Suppose then some manufacturer of fig paste or strawberry jam should put
in ten per cent. of little round hard wooden nodules, just the sort to
get stuck between the teeth or caught in the vermiform appendix. How
long would it be before he was sent to jail for adulterating food? But
neither jail nor boycott has any reformatory effect on Nature.
Nature is quite human in that respect. But you can reform Nature as you
can human beings by looking out for heredity and culture. In this way
Mother Nature has been quite cured of her bad habit of putting seeds in
bananas and oranges. Figs she still persists in adulterating with
particles of cellulose as nutritious as sawdust. But we can circumvent
the old lady at this. I got on Christmas a package of figs from
California without a seed in them. Somebody had taken out all the
seeds--it must have been a big job--and then put the figs together again
as natural looking as life and very much better tasting.
Sugar and alcohol are both found in Nature; sugar in the ripe fruit,
alcohol when it begins to decay. But it was the chemist who discovered
how to extract them. He first worked with alcohol and unfortunately
succeeded.
Previous to the invention of the still by the Arabian chemists man could
not get drunk as quickly as he wanted to because his liquors were
limited to what the yeast plant could stand without intoxication. When
the alcoholic content of wine or beer rose to seventeen per cent. at the
most the process of fermentation stopped because the yeast plants got
drunk and quit "working." That meant that a man confined to ordinary
wine or beer had to drink ten or twenty quarts of water to get one
quart of the stuff he was after, and he had no liking for water.
So the chemist helped him out of this difficulty and got him into worse
trouble by distilling the wine. The more volatile part that came over
first contained the flavor and most of the alcohol. In this way he could
get liquors like brandy and whisky, rum and gin, containing from thirty
to eighty per cent. of alcohol. This was the origin of the modern liquor
problem. The wine of the ancients was strong enough to knock out Noah
and put the companions of Socrates under the table, but it was not until
distilled liquors came in that alcoholism became chronic, epidemic and
ruinous to whole populations.
But the chemist later tried to undo the ruin he had quite inadvertently
wrought by introducing alcohol into the world. One of his most
successful measures was the production of cheap and pure sugar which, as
we have seen, has become a large factor in the dietary of civilized
countries. As a country sobers up it takes to sugar as a "self-starter"
to provide the energy needed for the strenuous life. A five o'clock
candy is a better restorative than a five o'clock highball or even a
five o'clock tea, for it is a true nutrient instead of a mere stimulant.
It is a matter of common observation that those who like sweets usually
do not like alcohol. Women, for instance, are apt to eat candy but do
not commonly take to alcoholic beverages. Look around you at a banquet
table and you will generally find that those who turn down their wine
glasses generally take two lumps in their demi-tasses. We often hear it
said that whenever a candy store opens up a saloon in the same block
closes up. Our grandmothers used to warn their daughters: "Don't marry a
man who does not want sugar in his tea. He is likely to take to drink."
So, young man, when next you give a box of candy to your best girl and
she offers you some, don't decline it. Eat it and pretend to like it, at
least, for it is quite possible that she looked into a physiology and is
trying you out. You never can tell what girls are up to.
In the army and navy ration the same change has taken place as in the
popular dietary. The ration of rum has been mostly replaced by an
equivalent amount of candy or marmalade. Instead of the tippling trooper
of former days we have "the chocolate soldier." No previous war in
history has been fought so largely on sugar and so little on alcohol as
the last one. When the war reduced the supply and increased the demand
we all felt the sugar famine and it became a mark of patriotism to
refuse candy and to drink coffee unsweetened. This, however, is not, as
some think, the mere curtailment of a superfluous or harmful luxury, the
sacrifice of a pleasant sensation. It is a real deprivation and a
serious loss to national nutrition. For there is no reason to think the
constantly rising curve of sugar consumption has yet reached its maximum
or optimum. Individuals overeat, but not the population as a whole.
According to experiments of the Department of Agriculture men doing
heavy labor may add three-quarters of a pound of sugar to their daily
diet without any deleterious effects. This is at the rate of 275 pounds
a year, which is three times the average consumption of England and
America. But the Department does not state how much a girl doing
nothing ought to eat between meals.
Of the 2500 to 3500 calories of energy required to keep a man going for
a day the best source of supply is the carbohydrates, that is, the
sugars and starches. The fats are more concentrated but are more
expensive and less easily assimilable. The proteins are also more
expensive and their decomposition products are more apt to clog up the
system. Common sugar is almost an ideal food. Cheap, clean, white,
portable, imperishable, unadulterated, pleasant-tasting, germ-free,
highly nutritious, completely soluble, altogether digestible, easily
assimilable, requires no cooking and leaves no residue. Its only fault
is its perfection. It is so pure that a man cannot live on it. Four
square lumps give one hundred calories of energy. But twenty-five or
thirty-five times that amount would not constitute a day's ration, in
fact one would ultimately starve on such fare. It would be like
supplying an army with an abundance of powder but neglecting to provide
any bullets, clothing or food. To make sugar the sole food is
impossible. To make it the main food is unwise. It is quite proper for
man to separate out the distinct ingredients of natural products--to
extract the butter from the milk, the casein from the cheese, the sugar
from the cane--but he must not forget to combine them again at each meal
with the other essential foodstuffs in their proper proportion.
[Illustration: THE RIVAL SUGARS The sugar beet of the north has become
a close rival of the sugar cane of the south]
[Illustration: INTERIOR OF A SUGAR MILL SHOWING THE MACHINERY FOR
CRUSHING CANE TO EXTRACT THE JUICE]
[Illustration: Courtesy of American Sugar Refinery Co.
VACUUM PANS OF THE AMERICAN SUGAR REFINERY COMPANY
In these air-tight vats the water is boiled off from the cane juice
under diminished atmospheric pressure until the sugar crystallizes out]
Sugar is not a synthetic product and the business of the chemist has
been merely to extract and purify it. But this is not so simple as it
seems and every sugar factory has had to have its chemist. He has
analyzed every mother beet for a hundred years. He has watched every
step of the process from the cane to the crystal lest the sucrose should
invert to the less sweet and non-crystallizable glucose. He has tested
with polarized light every shipment of sugar that has passed through the
custom house, much to the mystification of congressmen who have often
wondered at the money and argumentation expended in a tariff discussion
over the question of the precise angle of rotation of the plane of
vibration of infinitesimal waves in a hypothetical ether.
The reason for this painstaking is that there are dozens of different
sugars, so much alike that they are difficult to separate. They are all
composed of the same three elements, C, H and O, and often in the same
proportion. Sometimes two sugars differ only in that one has a
right-handed and the other a left-handed twist to its molecule. They
bear the same resemblance to one another as the two gloves of a pair.
Cane sugar and beet sugar are when completely purified the same
substance, that is, sucrose, C_{12}H_{22}O_{11}. The brown and
straw-colored sugars, which our forefathers used and which we took to
using during the war, are essentially the same but have not been so
completely freed from moisture and the coloring and flavoring matter of
the cane juice. Maple sugar is mostly sucrose. So partly is honey.
Candies are made chiefly of sucrose with the addition of glucose, gums
or starch, to give them the necessary consistency and of such colors and
flavors, natural or synthetic, as may be desired. Practically all candy,
even the cheapest, is nowadays free from deleterious ingredients in the
manufacture, though it is liable to become contaminated in the handling.
In fact sugar is about the only food that is never adulterated. It would
be hard to find anything cheaper to add to it that would not be easily
detected. "Sanding the sugar," the crime of which grocers are generally
accused, is the one they are least likely to be guilty of.
Besides the big family of sugars which are all more or less sweet,
similar in structure and about equally nutritious, there are, very
curiously, other chemical compounds of altogether different composition
which taste like sugar but are not nutritious at all. One of these is
a coal-tar derivative, discovered accidentally by an American student
of chemistry, Ira Remsen, afterward president of Johns Hopkins
University, and named by him "saccharin." This has the composition
C_{6}H_{4}COSO_{2}NH, and as you may observe from the symbol it contains
sulfur (S) and nitrogen (N) and the benzene ring (C_{6}H_{4}) that are
not found in any of the sugars. It is several hundred times sweeter than
sugar, though it has also a slightly bitter aftertaste. A minute
quantity of it can therefore take the place of a large amount of sugar
in syrups, candies and preserves, so because it lends itself readily to
deception its use in food has been prohibited in the United States and
other countries. But during the war, on account of the shortage of
sugar, it came again into use. The European governments encouraged what
they formerly tried to prevent, and it became customary in Germany or
Italy to carry about a package of saccharin tablets in the pocket and
drop one or two into the tea or coffee. Such reversals of administrative
attitude are not uncommon. When the use of hops in beer was new it was
prohibited by British law. But hops became customary nevertheless and
now the law requires hops to be used in beer. When workingmen first
wanted to form unions, laws were passed to prevent them. But now, in
Australia for instance, the laws require workingmen to form unions.
Governments naturally tend to a conservative reaction against anything
new.
It is amusing to turn back to the pure food agitation of ten years ago
and read the sensational articles in the newspapers about the poisonous
nature of this dangerous drug, saccharin, in view of the fact that it is
being used by millions of people in Europe in amounts greater than once
seemed to upset the tender stomachs of the Washington "poison squads."
But saccharin does not appear to be responsible for any fatalities yet,
though people are said to be heartily sick of it. And well they may be,
for it is not a substitute for sugar except to the sense of taste.
Glucose may correctly be called a substitute for sucrose as margarin for
butter, since they not only taste much the same but have about the same
food value. But to serve saccharin in the place of sugar is like giving
a rubber bone to a dog. It is reported from Europe that the constant use
of saccharin gives one eventually a distaste for all sweets. This is
quite likely, although it means the reversal within a few years of
prehistoric food habits. Mankind has always associated sweetness with
food value, for there are few sweet things found in nature except the
sugars. We think we eat sugar because it is sweet. But we do not. We eat
it because it is good for us. The reason it tastes sweet to us is
because it is good for us. So man makes a virtue out of necessity, a
pleasure out of duty, which is the essence of ethics.
In the ancient days of Ind the great Raja Trishanku possessed an earthly
paradise that had been constructed for his delectation by a magician.
Therein grew all manner of beautiful flowers, savory herbs and delicious
fruits such as had never been known before outside heaven. Of them all
the Raja and his harems liked none better than the reed from which they
could suck honey. But Indra, being a jealous god, was wroth when he
looked down and beheld mere mortals enjoying such delights. So he willed
the destruction of the enchanted garden. With drought and tempest it was
devastated, with fire and hail, until not a leaf was left of its
luxuriant vegetation and the ground was bare as a threshing floor. But
the roots of the sugar cane are not destroyed though the stalk be cut
down; so when men ventured to enter the desert where once had been this
garden of Eden, they found the cane had grown up again and they carried
away cuttings of it and cultivated it in their gardens. Thus it happened
that the nectar of the gods descended first to monarchs and their
favorites, then was spread among the people and carried abroad to other
lands until now any child with a penny in his hand may buy of the best
of it. So it has been with many things. So may it be with all things.
X
WHAT COMES FROM CORN
The discovery of America dowered mankind with a world of new flora. The
early explorers in their haste to gather up gold paid little attention
to the more valuable products of field and forest, but in the course of
centuries their usefulness has become universally recognized. The potato
and tomato, which Europe at first considered as unfit for food or even
as poisonous, have now become indispensable among all classes. New World
drugs like quinine and cocaine have been adopted into every
pharmacopeia. Cocoa is proving a rival of tea and coffee, and even the
banana has made its appearance in European markets. Tobacco and chicle
occupy the nostrils and jaws of a large part of the human race. Maize
and rubber are become the common property of mankind, but still may be
called American. The United States alone raises four-fifths of the corn
and uses three-fourths of the caoutchouc of the world.
All flesh is grass. This may be taken in a dietary as well as a
metaphorical sense. The graminaceae provide the greater part of the
sustenance of man and beast; hay and cereals, wheat, oats, rye, barley,
rice, sugar cane, sorghum and corn. From an American viewpoint the
greatest of these, physically and financially, is corn. The corn crop of
the United States for 1917, amounting to 3,159,000,000 bushels, brought
in more money than the wheat, cotton, potato and rye crops all
together.
When Columbus reached the West Indies he found the savages playing with
rubber balls, smoking incense sticks of tobacco and eating cakes made of
a new grain that they called _mahiz_. When Pizarro invaded Peru he found
this same cereal used by the natives not only for food but also for
making alcoholic liquor, in spite of the efforts of the Incas to enforce
prohibition. When the Pilgrim Fathers penetrated into the woods back of
Plymouth Harbor they discovered a cache of Indian corn. So throughout
the three Americas, from Canada to Peru, corn was king and it has proved
worthy to rank with the rival cereals of other continents, the wheat of
Europe and the rice of Asia. But food habits are hard to change and for
the most part the people of the Old World are still ignorant of the
delights of hasty pudding and Indian pudding, of hoe-cake and hominy, of
sweet corn and popcorn. I remember thirty years ago seeing on a London
stand a heap of dejected popcorn balls labeled "Novel American
Confection. Please Try One." But nobody complied with this pitiful
appeal but me and I was sorry that I did. Americans used to respond with
a shipload of corn whenever an appeal came from famine sufferers in
Armenia, Russia, Ireland, India or Austria, but their generosity was
chilled when they found that their gift was resented as an insult or as
an attempt to poison the impoverished population, who declared that they
would rather die than eat it--and some of them did. Our Department of
Agriculture sent maize missionaries to Europe with farmers and millers
as educators and expert cooks to serve free flapjacks and pones, but the
propaganda made little impression and today Americans are urged to eat
more of their own corn because the famished families of the war-stricken
region will not touch it. Just so the beggars of Munich revolted at
potato soup when the pioneer of American food chemists, Bumford,
attempted to introduce this transatlantic dish.
But here we are not so much concerned with corn foods as we are with its
manufactured products. If you split a kernel in two you will find that
it consists of three parts: a hard and horny hull on the outside, a
small oily and nitrogenous germ at the point, and a white body
consisting mostly of starch. Each of these is worked up into various
products, as may be seen from the accompanying table. The hull forms
bran and may be mixed with the gluten as a cattle food. The corn steeped
for several days with sulfurous acid is disintegrated and on being
ground the germs are floated off, the gluten or nitrogenous portion
washed out, the starch grains settled down and the residue pressed
together as oil cake fodder. The refined oil from the germ is marketed
as a table or cooking oil under the name of "Mazola" and comes into
competition with olive, peanut and cottonseed oil in the making of
vegetable substitutes for lard and butter. Inferior grades may be used
for soaps or for glycerin and perhaps nitroglycerin. A bushel of corn
yields a pound or more of oil. From the corn germ also is extracted a
gum called "paragol" that forms an acceptable substitute for rubber in
certain uses. The "red rubber" sponges and the eraser tips to pencils
may be made of it and it can contribute some twenty per cent. to the
synthetic soles of shoes.
[Illustration: CORN PRODUCTS]
Starch, which constitutes fifty-five per cent. of the corn kernel, can
be converted into a variety of products for dietary and industrial uses.
As found in corn, potatoes or any other vegetables starch consists of
small, round, white, hard grains, tasteless, and insoluble in cold
water. But hot water converts it into a soluble, sticky form which may
serve for starching clothes or making cornstarch pudding. Carrying the
process further with the aid of a little acid or other catalyst it takes
up water and goes over into a sugar, dextrose, commonly called
"glucose." Expressed in chemical shorthand this reaction is
C_{6}H_{10}O_{5} + H_{2}O --> C_{6}H_{12}O_{6}
starch water dextrose
This reaction is carried out on forty million bushels of corn a year in
the United States. The "starch milk," that is, the starch grains washed
out from the disintegrated corn kernel by water, is digested in large
pressure tanks under fifty pounds of steam with a few tenths of one per
cent. of hydrochloric acid until the required degree of conversion is
reached. Then the remaining acid is neutralized by caustic soda, and
thereby converted into common salt, which in this small amount does not
interfere but rather enhances the taste. The product is the commercial
glucose or corn syrup, which may if desired be evaporated to a white
powder. It is a mixture of three derivatives of starch in about this
proportion:
Maltose 45 per cent.
Dextrose 20 per cent.
Dextrin 35 per cent.
There are also present three- or four-tenths of one per cent. salt and
as much of the corn protein and a variable amount of water. It will be
noticed that the glucose (dextrose), which gives name to the whole, is
the least of the three ingredients.
Maltose, or malt sugar, has the same composition as cane sugar
(C_{12}H_{22}O_{11}), but is not nearly so sweet. Dextrin, or starch
paste, is not sweet at all. Dextrose or glucose is otherwise known; as
grape sugar, for it is commonly found in grapes and other ripe fruits.
It forms half of honey and it is one of the two products into which
cane sugar splits up when we take it into the mouth. It is not so sweet
as cane sugar and cannot be so readily crystallized, which, however, is
not altogether a disadvantage.
The process of changing starch into dextrose that takes place in the
great steam kettles of the glucose factory is essentially the same as
that which takes place in the ripening of fruit and in the digestion of
starch. A large part of our nutriment, therefore, consists of glucose
either eaten as such in ripe fruits or produced in the mouth or stomach
by the decomposition of the starch of unripe fruit, vegetables and
cereals. Glucose may be regarded as a predigested food. In spite of this
well-known fact we still sometimes read "poor food" articles in which
glucose is denounced as a dangerous adulterant and even classed as a
poison.
The other ingredients of commercial glucose, the maltose and dextrin,
have of course the same food value as the dextrose, since they are made
over into dextrose in the process of digestion. Whether the glucose
syrup is fit to eat depends, like anything else, on how it is made. If,
as was formerly sometimes the case, sulfuric acid was used to effect the
conversion of the starch or sulfurous acid to bleach the glucose and
these acids were not altogether eliminated, the product might be
unwholesome or worse. Some years ago in England there was a mysterious
epidemic of arsenical poisoning among beer drinkers. On tracing it back
it was found that the beer had been made from glucose which had been
made from sulfuric acid which had been made from sulfur which had been
made from a batch of iron pyrites which contained a little arsenic. The
replacement of sulfuric acid by hydrochloric has done away with that
danger and the glucose now produced is pure.
The old recipe for home-made candy called for the addition of a little
vinegar to the sugar syrup to prevent "graining." The purpose of the
acid was of course to invert part of the cane sugar to glucose so as to
keep it from crystallizing out again. The professional candy-maker now
uses the corn glucose for that purpose, so if we accuse him of
"adulteration" on that ground we must levy the same accusation against
our grandmothers. The introduction of glucose into candy manufacture has
not injured but greatly increased the sale of sugar for the same
purpose. This is not an uncommon effect of scientific progress, for as
we have observed, the introduction of synthetic perfumes has stimulated
the production of odoriferous flowers and the price of butter has gone
up with the introduction of margarin. So, too, there are more weavers
employed and they get higher wages than in the days when they smashed up
the first weaving machines, and the same is true of printers and
typesetting machines. The popular animosity displayed toward any new
achievement of applied science is never justified, for it benefits not
only the world as a whole but usually even those interests with which it
seems at first to conflict.
The chemist is an economizer. It is his special business to hunt up
waste products and make them useful. He was, for instance, worried over
the waste of the cores and skins and scraps that were being thrown away
when apples were put up. Apple pulp contains pectin, which is what makes
jelly jell, and berries and fruits that are short of it will refuse to
"jell." But using these for their flavor he adds apple pulp for pectin
and glucose for smoothness and sugar for sweetness and, if necessary,
synthetic dyes for color, he is able to put on the market a variety of
jellies, jams and marmalades at very low price. The same principle
applies here as in the case of all compounded food products. If they are
made in cleanly fashion, contain no harmful ingredients and are
truthfully labeled there is no reason for objecting to them. But if the
manufacturer goes so far as to put strawberry seeds--or hayseed--into
his artificial "strawberry jam" I think that might properly be called
adulteration, for it is imitating the imperfections of nature, and man
ought to be too proud to do that.
The old-fashioned open kettle molasses consisted mostly of glucose and
other invert sugars together with such cane sugar as could not be
crystallized out. But when the vacuum pan was introduced the molasses
was impoverished of its sweetness and beet sugar does not yield any
molasses. So we now have in its place the corn syrups consisting of
about 85 per cent. of glucose and 15 per cent. of sugar flavored with
maple or vanillin or whatever we like. It is encouraging to see the bill
boards proclaiming the virtues of "Karo" syrup and "Mazola" oil when
only a few years ago the products of our national cereal were without
honor in their own country.
Many other products besides foods are made from corn starch. Dextrin
serves in place of the old "gum arabic" for the mucilage of our
envelopes and stamps. Another form of dextrin sold as "Kordex" is used
to hold together the sand of the cores of castings. After the casting
has been made the scorched core can be shaken out. Glucose is used in
place of sugar as a filler for cheap soaps and for leather.
Altogether more than a hundred different commercial products are now
made from corn, not counting cob pipes. Every year the factories of the
United States work up over 50,000,000 bushels of corn into 800,000,000
pounds of corn syrup, 600,000,000 pounds of starch, 230,000,000 pounds
of corn sugar, 625,000,000 pounds of gluten feed, 90,000,000 pounds of
oil and 90,000,000 pounds of oil cake.
Two million bushels of cobs are wasted every year in the United States.
Can't something be made out of them? This is the question that is
agitating the chemists of the Carbohydrate Laboratory of the Department
of Agriculture at Washington. They have found it possible to work up the
corn cobs into glucose and xylose by heating with acid. But glucose can
be more cheaply obtained from other starchy or woody materials and they
cannot find a market for the xylose. This is a sort of a sugar but only
about half as sweet as that from cane. Who can invent a use for it! More
promising is the discovery by this laboratory that by digesting the cobs
with hot water there can be extracted about 30 per cent. of a gum
suitable for bill posting and labeling.
Since the starches and sugars belong to the same class of compounds as
the celluloses they also can be acted upon by nitric acid with the
production of explosives like guncotton. Nitro-sugar has not come into
common use, but nitro-starch is found to be one of safest of the high
explosives. On account of the danger of decomposition and spontaneous
explosion from the presence of foreign substances the materials in
explosives must be of the purest possible. It was formerly thought that
tapioca must be imported from Java for making nitro-starch. But during
the war when shipping was short, the War Department found that it could
be made better and cheaper from our home-grown corn starch. When the war
closed the United States was making 1,720,000 pounds of nitro-starch a
month for loading hand grenades. So, too, the Post Office Department
discovered that it could use mucilage made of corn dextrin as well as
that which used to be made from tapioca. This is progress in the right
direction. It would be well to divert some of the energetic efforts now
devoted to the increase of commerce to the discovery of ways of reducing
the need for commerce by the development of home products. There is no
merit in simply hauling things around the world.
In the last chapter we saw how dextrose or glucose could be converted by
fermentation into alcohol. Since corn starch, as we have seen, can be
converted into dextrose, it can serve as a source of alcohol. This was,
in fact, one of the earliest misuses to which corn was put, and before
the war put a stop to it 34,000,000 bushels went into the making of
whiskey in the United States every year, not counting the moonshiners'
output. But even though we left off drinking whiskey the distillers
could still thrive. Mars is more thirsty than Bacchus. The output of
whiskey, denatured for industrial purposes, is more than three times
what is was before the war, and the price has risen from 30 cents a
gallon to 67 cents. This may make it profitable to utilize sugars,
starches and cellulose that formerly were out of the question. According
to the calculations of the Forest Products Laboratory of Madison it
costs from 37 to 44 cents a gallon to make alcohol from corn, but it may
be made from sawdust at a cost of from 14 to 20 cents. This is not "wood
alcohol" (that is, methyl alcohol, CH_{4}O) such as is made by the
destructive distillation of wood, but genuine "grain alcohol" (ethyl
alcohol, C_{2}H_{6}O), such as is made by the fermentation of glucose or
other sugar. The first step in the process is to digest the sawdust or
chips with dilute sulfuric acid under heat and pressure. This converts
the cellulose (wood fiber) in large part into glucose ("corn sugar")
which may be extracted by hot water in a diffusion battery as in
extracting the sugar from beet chips. This glucose solution may then be
fermented by yeast and the resulting alcohol distilled off. The process
is perfectly practicable but has yet to be proved profitable. But the
sulfite liquors of the paper mills are being worked up successfully into
industrial alcohol.
The rapidly approaching exhaustion of our oil fields which the war has
accelerated leads us to look around to see what we can get to take the
place of gasoline. One of the most promising of the suggested
substitutes is alcohol. The United States is exceptionally rich in
mineral oil, but some countries, for instance England, Germany, France
and Australia, have little or none. The Australian Advisory Council of
Science, called to consider the problem, recommends alcohol for
stationary engines and motor cars. Alcohol has the disadvantage of
being less volatile than gasoline so it is hard to start up the engine
from the cold. But the lower volatility and ignition point of alcohol
are an advantage in that it can be put under a pressure of 150 pounds to
the square inch. A pound of gasoline contains fifty per cent. more
potential energy than a pound of alcohol, but since the alcohol vapor
can be put under twice the compression of the gasoline and requires only
one-third the amount of air, the thermal efficiency of an alcohol engine
may be fifty per cent. higher than that of a gasoline engine. Alcohol
also has several other conveniences that can count in its favor. In the
case of incomplete combustion the cylinders are less likely to be
clogged with carbon and the escaping gases do not have the offensive
odor of the gasoline smoke. Alcohol does not ignite so easily as
gasoline and the fire is more readily put out, for water thrown upon
blazing alcohol dilutes it and puts out the flame while gasoline floats
on water and the fire is spread by it. It is possible to increase the
inflammability of alcohol by mixing with it some hydrocarbon such as
gasoline, benzene or acetylene. In the Taylor-White process the vapor
from low-grade alcohol containing 17 per cent. water is passed over
calcium carbide. This takes out the water and adds acetylene gas, making
a suitable mixture for an internal combustion engine.
Alcohol can be made from anything of a starchy, sugary or woody nature,
that is, from the main substance of all vegetation. If we start with
wood (cellulose) we convert it first into sugar (glucose) and, of
course, we could stop here and use it for food instead of carrying it
on into alcohol. This provides one factor of our food, the carbohydrate,
but by growing the yeast plants on glucose and feeding them with
nitrates made from the air we can get the protein and fat. So it is
quite possible to live on sawdust, although it would be too expensive a
diet for anybody but a millionaire, and he would not enjoy it. Glucose
has been made from formaldehyde and this in turn made from carbon,
hydrogen and oxygen, so the synthetic production of food from the
elements is not such an absurdity as it was thought when Berthelot
suggested it half a century ago.
The first step in the making of alcohol is to change the starch over
into sugar. This transformation is effected in the natural course of
sprouting by which the insoluble starch stored up in the seed is
converted into the soluble glucose for the sap of the growing plant.
This malting process is that mainly made use of in the production of
alcohol from grain. But there are other ways of effecting the change. It
may be done by heating with acid as we have seen, or according to a
method now being developed the final conversion may be accomplished by
mold instead of malt. In applying this method, known as the amylo
process, to corn, the meal is mixed with twice its weight of water,
acidified with hydrochloric acid and steamed. The mash is then cooled
down somewhat, diluted with sterilized water and innoculated with the
mucor filaments. As the mash molds the starch is gradually changed over
to glucose and if this is the product desired the process may be stopped
at this point. But if alcohol is wanted yeast is added to ferment the
sugar. By keeping it alkaline and treating with the proper bacteria a
high yield of glycerin can be obtained.
In the fermentation process for making alcoholic liquors a little
glycerin is produced as a by-product. Glycerin, otherwise called
glycerol, is intermediate between sugar and alcohol. Its molecule
contains three carbon atoms, while glucose has six and alcohol two. It
is possible to increase the yield of glycerin if desired by varying the
form of fermentation. This was desired most earnestly in Germany during
the war, for the British blockade shut off the importation of the fats
and oils from which the Germans extracted the glycerin for their
nitroglycerin. Under pressure of this necessity they worked out a
process of getting glycerin in quantity from sugar and, news of this
being brought to this country by Dr. Alonzo Taylor, the United States
Treasury Department set up a special laboratory to work out this
problem. John R. Eoff and other chemists working in this laboratory
succeeded in getting a yield of twenty per cent. of glycerin by
fermenting black strap molasses or other syrup with California wine
yeast. During the fermentation it is necessary to neutralize the acetic
acid formed with sodium or calcium carbonate. It was estimated that
glycerin could be made from waste sugars at about a quarter of its
war-time cost, but it is doubtful whether the process would be
profitable at normal prices.
We can, if we like, dispense with either yeast or bacteria in the
production of glycerin. Glucose syrup suspended in oil under steam
pressure with finely divided nickel as a catalyst and treated with
nascent hydrogen will take up the hydrogen and be converted into
glycerin. But the yield is poor and the process expensive.
Food serves substantially the same purpose in the body as fuel in the
engine. It provides the energy for work. The carbohydrates, that is the
sugars, starches and celluloses, can all be used as fuels and can
all--even, as we have seen, the cellulose--be used as foods. The final
products, water and carbon dioxide, are in both cases the same and
necessarily therefore the amount of energy produced is the same in the
body as in the engine. Corn is a good example of the equivalence of the
two sources of energy. There are few better foods and no better fuels. I
can remember the good old days in Kansas when we had corn to burn. It
was both an economy and a luxury, for--at ten cents a bushel--it was
cheaper than coal or wood and preferable to either at any price. The
long yellow ears, each wrapped in its own kindling, could be handled
without crocking the fingers. Each kernel as it crackled sent out a
blazing jet of oil and the cobs left a fine bed of coals for the corn
popper to be shaken over. Driftwood and the pyrotechnic fuel they make
now by soaking sticks in strontium and copper salts cannot compare with
the old-fashioned corn-fed fire in beauty and the power of evoking
visions. Doubtless such luxury would be condemned as wicked nowadays,
but those who have known the calorific value of corn would find it hard
to abandon it altogether, and I fancy that the Western farmer's wife,
when she has an extra batch of baking to do, will still steal a few ears
from the crib.
XI
SOLIDIFIED SUNSHINE
All life and all that life accomplishes depend upon the supply of solar
energy stored in the form of food. The chief sources of this vital
energy are the fats and the sugars. The former contain two and a quarter
times the potential energy of the latter. Both, when completely
purified, consist of nothing but carbon, hydrogen and oxygen; elements
that are to be found freely everywhere in air and water. So when the
sunny southland exports fats and oils, starches and sugar, it is then
sending away nothing material but what comes back to it in the next
wind. What it is sending to the regions of more slanting sunshine is
merely some of the surplus of the radiant energy it has received so
abundantly, compacted for convenience into a portable and edible form.
In previous chapters I have dealt with some of the uses of cotton, its
employment for cloth, for paper, for artificial fibers, for explosives,
and for plastics. But I have ignored the thing that cotton is attached
to and for which, in the economy of nature, the fibers are formed; that
is, the seed. It is as though I had described the aeroplane and ignored
the aviator whom it was designed to carry. But in this neglect I am but
following the example of the human race, which for three thousand years
used the fiber but made no use of the seed except to plant the next
crop.
Just as mankind is now divided into the two great classes, the
wheat-eaters and the rice-eaters, so the ancient world was divided into
the wool-wearers and the cotton-wearers. The people of India wore
cotton; the Europeans wore wool. When the Greeks under Alexander fought
their way to the Far East they were surprised to find wool growing on
trees. Later travelers returning from Cathay told of the same marvel and
travelers who stayed at home and wrote about what they had not seen,
like Sir John Maundeville, misunderstood these reports and elaborated a
legend of a tree that bore live lambs as fruit. Here, for instance, is
how a French poetical botanist, Delacroix, described it in 1791, as
translated from his Latin verse:
Upon a stalk is fixed a living brute,
A rooted plant bears quadruped for fruit;
It has a fleece, nor does it want for eyes,
And from its brows two wooly horns arise.
The rude and simple country people say
It is an animal that sleeps by day
And wakes at night, though rooted to the ground,
To feed on grass within its reach around.
But modern commerce broke down the barrier between East and West. A new
cotton country, the best in the world, was discovered in America. Cotton
invaded England and after a hard fight, with fists as well as finance,
wool was beaten in its chief stronghold. Cotton became King and the
wool-sack in the House of Lords lost its symbolic significance.
Still two-thirds of the cotton crop, the seed, was wasted and it is only
within the last fifty years that methods of using it have been
developed to any extent.
The cotton crop of the United States for 1917 amounted to about
11,000,000 bales of 500 pounds each. When the Great War broke out and no
cotton could be exported to Germany and little to England the South was
in despair, for cotton went down to five or six cents a pound. The
national Government, regardless of states' rights, was called upon for
aid and everybody was besought to "buy a bale." Those who responded to
this patriotic appeal were well rewarded, for cotton rose as the war
went on and sold at twenty-nine cents a pound.
[ILLUSTRATION: PRODUCTS AND USES OF COTTONSEED]
But the chemist has added some $150,000,000 a year to the value of the
crop by discovering ways of utilizing the cottonseed that used to be
thrown away or burned as fuel. The genealogical table of the progeny of
the cottonseed herewith printed will give some idea of their variety. If
you will examine a cottonseed you will see first that there is a fine
fuzz of cotton fiber sticking to it. These linters can be removed by
machinery and used for any purpose where length of fiber is not
essential. For instance, they may be nitrated as described in previous
articles and used for making smokeless powder or celluloid.
On cutting open the seed you will observe that it consists of an oily,
mealy kernel encased in a thin brown hull. The hulls, amounting to 700
or 900 pounds in a ton of seed, were formerly burned. Now, however, they
bring from $4 to $10 a ton because they can be ground up into
cattle-feed or paper stock or used as fertilizer.
The kernel of the cottonseed on being pressed yields a yellow oil and
leaves a mealy cake. This last, mixed with the hulls, makes a good
fodder for fattening cattle. Also, adding twenty-five per cent. of the
refined cottonseed meal to our war bread made it more nutritious and no
less palatable. Cottonseed meal contains about forty per cent. of
protein and is therefore a highly concentrated and very valuable feeding
stuff. Before the war we were exporting nearly half a million tons of
cottonseed meal to Europe, chiefly to Germany and Denmark, where it is
used for dairy cows. The British yeoman, his country's pride, has not
yet been won over to the use of any such newfangled fodder and
consequently the British manufacturer could not compete with his
continental rivals in the seed-crushing business, for he could not
dispose of his meal-cake by-product as did they.
[Illustration: Photo by Press Illustrating Service
Cottonseed Oil As It Is Squeezed From The Seed By The Presses]
[Illustration: Photo by Press Illustrating Service
Cottonseed Oil As It Comes From The Compressors Flowing Out Of The
Faucets
When cold it is firm and white like lard]
Let us now turn to the most valuable of the cottonseed products, the
oil. The seed contains about twenty per cent. of oil, most of which can
be squeezed out of the hot seeds by hydraulic pressure. It comes out as
a red liquid of a disagreeable odor. This is decolorized, deodorized and
otherwise purified in various ways: by treatment with alkalies or acids,
by blowing air and steam through it, by shaking up with fuller's earth,
by settling and filtering. The refined product is a yellow oil, suitable
for table use. Formerly, on account of the popular prejudice against any
novel food products, it used to masquerade as olive oil. Now, however,
it boldly competes with its ancient rival in the lands of the olive tree
and America ships some 700,000 barrels of cottonseed oil a year to the
Mediterranean. The Turkish Government tried to check the spread of
cottonseed oil by calling it an adulterant and prohibiting its mixture
with olive oil. The result was that the sale of Turkish olive oil fell
off because people found its flavor too strong when undiluted. Italy
imports cottonseed oil and exports her olive oil. Denmark imports
cottonseed meal and margarine and exports her butter.
Northern nations are accustomed to hard fats and do not take to oils for
cooking or table use as do the southerners. Butter and lard are
preferred to olive oil and ghee. But this does not rule out cottonseed.
It can be combined with the hard fats of animal or vegetable origin in
margarine or it may itself be hardened by hydrogen.
To understand this interesting reaction which is profoundly affecting
international relations it will be necessary to dip into the chemistry
of the subject. Here are the symbols of the chief ingredients of the
fats and oils. Please look at them.
Linoleic acid C_{18}H_{32}O_{2}
Oleic acid C_{18}H_{34}O_{2}
Stearic acid C_{18}H_{36}O_{2}
Don't skip these because you have not studied chemistry. That's why I am
giving them to you. If you had studied chemistry you would know them
without my telling. Just examine them and you will discover the secret.
You will see that all three are composed of the same elements, carbon,
hydrogen, and oxygen. Notice next the number of atoms in each element as
indicated by the little low figures on the right of each letter. You
observe that all three contain the same number of atoms of carbon and
oxygen but differ in the amount of hydrogen. This trifling difference in
composition makes a great difference in behavior. The less the hydrogen
the lower the melting point. Or to say the same thing in other words,
fatty substances low in hydrogen are apt to be liquids and those with a
full complement of hydrogen atoms are apt to be solids at the ordinary
temperature of the air. It is common to call the former "oils" and the
latter "fats," but that implies too great a dissimilarity, for the
distinction depends on whether we are living in the tropics or the
arctic. It is better, therefore, to lump them all together and call
them "soft fats" and "hard fats," respectively.
Fats of the third order, the stearic group, are called "saturated"
because they have taken up all the hydrogen they can hold. Fats of the
other two groups are called "unsaturated." The first, which have the
least hydrogen, are the most eager for more. If hydrogen is not handy
they will take up other things, for instance oxygen. Linseed oil, which
consists largely, as the name implies, of linoleic acid, will absorb
oxygen on exposure to the air and become hard. That is why it is used in
painting. Such oils are called "drying" oils, although the hardening
process is not really drying, since they contain no water, but is
oxidation. The "semi-drying oils," those that will harden somewhat on
exposure to the air, include the oils of cottonseed, corn, sesame, soy
bean and castor bean. Olive oil and peanut oil are "non-drying" and
contain oleic compounds (olein). The hard fats, such as stearin,
palmitin and margarin, are mostly of animal origin, tallow and lard,
though coconut and palm oil contain a large proportion of such saturated
compounds.
Though the chemist talks of the fatty "acids," nobody else would call
them so because they are not sour. But they do behave like the acids in
forming salts with bases. The alkali salts of the fatty acids are known
to us as soaps. In the natural fats they exist not as free acids but as
salts of an organic base, glycerin, as I explained in a previous
chapter. The natural fats and oils consist of complex mixtures of the
glycerin compounds of these acids (known as olein, stearin, etc.), as
well as various others of a similar sort. If you will set a bottle of
salad oil in the ice-box you will see it separate into two parts. The
white, crystalline solid that separates out is largely stearin. The part
that remains liquid is largely olein. You might separate them by
filtering it cold and if then you tried to sell the two products you
would find that the hard fat would bring a higher price than the oil,
either for food or soap. If you tried to keep them you would find that
the hard fat kept neutral and "sweet" longer than the other. You may
remember that the perfumes (as well as their odorous opposites) were
mostly unsaturated compounds. So we find that it is the free and
unsaturated fatty acids that cause butter and oil to become rank and
rancid.
Obviously, then, we could make money if we could turn soft, unsaturated
fats like olein into hard, saturated fats like stearin. Referring to the
symbols we see that all that is needed to effect the change is to get
the former to unite with hydrogen. This requires a little coaxing. The
coaxer is called a catalyst. A catalyst, as I have previously explained,
is a substance that by its mere presence causes the union of two other
substances that might otherwise remain separate. For that reason the
catalyst is referred to as "a chemical parson." Finely divided metals
have a strong catalytic action. Platinum sponge is excellent but too
expensive. So in this case nickel is used. A nickel salt mixed with
charcoal or pumice is reduced to the metallic state by heating in a
current of hydrogen. Then it is dropped into the tank of oil and
hydrogen gas is blown through. The hydrogen may be obtained by splitting
water into its two components, hydrogen and oxygen, by means of the
electrical current, or by passing steam over spongy iron which takes out
the oxygen. The stream of hydrogen blown through the hot oil converts
the linoleic acid to oleic and then the oleic into stearic. If you
figured up the weights from the symbols given above you would find that
it takes about one pound of hydrogen to convert a hundred pounds of
olein to stearin and the cost is only about one cent a pound. The nickel
is unchanged and is easily separated. A trace of nickel may remain in
the product, but as it is very much less than the amount dissolved when
food is cooked in nickel-plated vessels it cannot be regarded as
harmful.
Even more unsaturated fats may be hydrogenated. Fish oil has hitherto
been almost unusable because of its powerful and persistent odor. This
is chiefly due to a fatty acid which properly bears the uneuphonious
name of clupanodonic acid and has the composition of C_{18}H_{28}O_{2}.
By comparing this with the symbol of the odorless stearic acid,
C_{18}H_{36}O_{2}, you will see that all the rank fish oil lacks to make
it respectable is eight hydrogen atoms. A Japanese chemist, Tsujimoto,
has discovered how to add them and now the reformed fish oil under the
names of "talgol" and "candelite" serves for lubricant and even enters
higher circles as a soap or food.
This process of hardening fats by hydrogenation resulted from the
experiments of a French chemist, Professor Sabatier of Toulouse, in the
last years of the last century, but, as in many other cases, the Germans
were the first to take it up and profit by it. Before the war the copra
or coconut oil from the British Asiatic colonies of India, Ceylon and
Malaya went to Germany at the rate of $15,000,000 a year. The palm
kernels grown in British West Africa were shipped, not to Liverpool, but
to Hamburg, $19,000,000 worth annually. Here the oil was pressed out and
used for margarin and the residual cake used for feeding cows produced
butter or for feeding hogs produced lard. Half of the copra raised in
the British possessions was sent to Germany and half of the oil from it
was resold to the British margarin candle and soap makers at a handsome
profit. The British chemists were not blind to this, but they could do
nothing, first because the English politician was wedded to free trade,
second, because the English farmer would not use oil cake for his stock.
France was in a similar situation. Marseilles produced 15,500,000
gallons of oil from peanuts grown largely in the French African
colonies--but shipped the oil-cake on to Hamburg. Meanwhile the Germans,
in pursuit of their policy of attaining economic independence, were
striving to develop their own tropical territory. The subjects of King
George who because they had the misfortune to live in India were
excluded from the British South African dominions or mistreated when
they did come, were invited to come to German East Africa and set to
raising peanuts in rivalry to French Senegal and British Coromandel.
Before the war Germany got half of the Egyptian cottonseed and half of
the Philippine copra. That is one of the reasons why German warships
tried to check Dewey at Manila in 1898 and German troops tried to
conquer Egypt in 1915.
But the tide of war set the other way and the German plantations of
palmnuts and peanuts in Africa have come into British possession and
now the British Government is starting an educational campaign to teach
their farmers to feed oil cake like the Germans and their people to eat
peanuts like the Americans.
The Germans shut off from the tropical fats supply were hard up for food
and for soap, for lubricants and for munitions. Every person was given a
fat card that reduced his weekly allowance to the minimum. Millers were
required to remove the germs from their cereals and deliver them to the
war department. Children were set to gathering horse-chestnuts,
elderberries, linden-balls, grape seeds, cherry stones and sunflower
heads, for these contain from six to twenty per cent. of oil. Even the
blue-bottle fly--hitherto an idle creature for whom Beelzebub found
mischief--was conscripted into the national service and set to laying
eggs by the billion on fish refuse. Within a few days there is a crop of
larvae which, to quote the "Chemische Zentralblatt," yields forty-five
grams per kilogram of a yellow oil. This product, we should hope, is
used for axle-grease and nitroglycerin, although properly purified it
would be as nutritious as any other--to one who has no imagination.
Driven to such straits Germany would have given a good deal for one of
those tropical islands that we are so careless about.
It might have been supposed that since the United States possessed the
best land in the world for the production of cottonseed, coconuts,
peanuts, and corn that it would have led all other countries in the
utilization of vegetable oils for food. That this country has not so
used its advantage is due to the fact that the new products have not
merely had to overcome popular conservatism, ignorance and
prejudice--hard things to fight in any case--but have been deliberately
checked and hampered by the state and national governments in defense of
vested interests. The farmer vote is a power that no politician likes to
defy and the dairy business in every state was thoroughly organized. In
New York the oleomargarin industry that in 1879 was turning out products
valued at more than $5,000,000 a year was completely crushed out by
state legislation.[2] The output of the United States, which in 1902 had
risen to 126,000,000 pounds, was cut down to 43,000,000 pounds in 1909
by federal legislation. According to the disingenuous custom of American
lawmakers the Act of 1902 was passed through Congress as a "revenue
measure," although it meant a loss to the Government of more than three
million dollars a year over what might be produced by a straight two
cents a pound tax. A wholesale dealer in oleomargarin was made to pay a
higher license than a wholesale liquor dealer. The federal law put a tax
of ten cents a pound on yellow oleomargarin and a quarter of a cent a
pound on the uncolored. But people--doubtless from pure
prejudice--prefer a yellow spread for their bread, so the economical
housewife has to work over her oleomargarin with the annatto which is
given to her when she buys a package or, if the law prohibits this,
which she is permitted to steal from an open box on the grocer's
counter. A plausible pretext for such legislation is afforded by the
fact that the butter substitutes are so much like butter that they
cannot be easily distinguished from it unless the use of annatto is
permitted to butter and prohibited to its competitors. Fradulent sales
of substitutes of any kind ought to be prevented, but the recent pure
food legislation in America has shown that it is possible to secure
truthful labeling without resorting to such drastic measures. In Europe
the laws against substitution were very strict, but not devised to
restrict the industry. Consequently the margarin output of Germany
doubled in the five years preceding the war and the output of England
tripled. In Denmark the consumption of margarin rose from 8.8 pounds per
capita in 1890 to 32.6 pounds in 1912. Yet the butter business,
Denmark's pride, was not injured, and Germany and England imported more
butter than ever before. Now that the price of butter in America has
gone over the seventy-five cent mark Congress may conclude that it no
longer needs to be protected against competition.
The "compound lards" or "lard compounds," consisting usually of
cottonseed oil and oleo-stearin, although the latter may now be replaced
by hardened oil, met with the same popular prejudice and attempted
legislative interference, but succeeded more easily in coming into
common use under such names as "Cottosuet," "Kream Krisp," "Kuxit,"
"Korno," "Cottolene" and "Crisco."
Oleomargarin, now generally abbreviated to margarin, originated, like
many other inventions, in military necessity. The French Government in
1869 offered a prize for a butter substitute for the army that should be
cheaper and better than butter in that it did not spoil so easily. The
prize was won by a French chemist, Mége-Mouries, who found that by
chilling beef fat the solid stearin could be separated from an oil
(oleo) which was the substantially same as that in milk and hence in
butter. Neutral lard acts the same.
This discovery of how to separate the hard and soft fats was followed by
improved methods for purifying them and later by the process for
converting the soft into the hard fats by hydrogenation. The net result
was to put into the hands of the chemist the ability to draw his
materials at will from any land and from the vegetable and animal
kingdoms and to combine them as he will to make new fat foods for every
use; hard for summer, soft for winter; solid for the northerners and
liquid for the southerners; white, yellow or any other color, and
flavored to suit the taste. The Hindu can eat no fat from the sacred
cow; the Mohammedan and the Jew can eat no fat from the abhorred pig;
the vegetarian will touch neither; other people will take both. No
matter, all can be accommodated.
All the fats and oils, though they consist of scores of different
compounds, have practically the same food value when freed from the
extraneous matter that gives them their characteristic flavors. They are
all practically tasteless and colorless. The various vegetable and
animal oils and fats have about the same digestibility, 98 per cent.,[3]
and are all ordinarily completely utilized in the body, supplying it
with two and a quarter times as much energy as any other food.
It does not follow, however, that there is no difference in the
products. The margarin men accuse butter of harboring tuberculosis germs
from which their product, because it has been heated or is made from
vegetable fats, is free. The butter men retort that margarin is lacking
in vitamines, those mysterious substances which in minute amounts are
necessary for life and especially for growth. Both the claim and the
objection lose a large part of their force where the margarin, as is
customarily the case, is mixed with butter or churned up with milk to
give it the familiar flavor. But the difficulty can be easily overcome.
The milk used for either butter or margarin should be free or freed from
disease germs. If margarin is altogether substituted for butter, the
necessary vitamines may be sufficiently provided by milk, eggs and
greens.
Owing to these new processes all the fatty substances of all lands have
been brought into competition with each other. In such a contest the
vegetable is likely to beat the animal and the southern to win over the
northern zones. In Europe before the war the proportion of the various
ingredients used to make butter substitutes was as follows:
AVERAGE COMPOSITION OF EUROPEAN MARGARIN
Per Cent.
Animal hard fats 25
Vegetable hard fats 35
Copra 29
Palm-kernel 6
Vegetable soft fats 26
Cottonseed 13
Peanut 6
Sesame 6
Soya-bean 1
Water, milk, salt 14
___
100
This is not the composition of any particular brand but the average of
them all. The use of a certain amount of the oil of the sesame seed is
required by the laws of Germany and Denmark because it can be easily
detected by a chemical color test and so serves to prevent the margarin
containing it from being sold as butter. "Open sesame!" is the password
to these markets. Remembering that margarin originally was made up
entirely of animal fats, soft and hard, we can see from the above
figures how rapidly they are being displaced by the vegetable fats. The
cottonseed and peanut oils have replaced the original oleo oil and the
tropical oils from the coconut (copra) and African palm are crowding out
the animal hard fats. Since now we can harden at will any of the
vegetable oils it is possible to get along altogether without animal
fats. Such vegetable margarins were originally prepared for sale in
India, but proved unexpectedly popular in Europe, and are now being
introduced into America. They are sold under various trade names
suggesting their origin, such as "palmira," "palmona," "milkonut,"
"cocose," "coconut oleomargarin" and "nucoa nut margarin." The last
named is stated to be made of coconut oil (for the hard fat) and peanut
oil (for the soft fat), churned up with a culture of pasteurized milk
(to impart the butter flavor). The law requires such a product to be
branded "oleomargarine" although it is not. Such cases of compulsory
mislabeling are not rare. You remember the "Pigs is Pigs" story.
Peanut butter has won its way into the American menu without any
camouflage whatever, and as a salad oil it is almost equally frank about
its lowly origin. This nut, which grows on a vine instead of a tree,
and is dug from the ground like potatoes instead of being picked with a
pole, goes by various names according to locality, peanuts, ground-nuts,
monkey-nuts, arachides and goobers. As it takes the place of cotton oil
in some of its products so it takes its place in the fields and oilmills
of Texas left vacant by the bollweevil. The once despised peanut added
some $56,000,000 to the wealth of the South in 1916. The peanut is rich
in the richest of foods, some 50 per cent. of oil and 30 per cent. of
protein. The latter can be worked up into meat substitutes that will
make the vegetarian cease to envy his omnivorous neighbor. Thanks
largely to the chemist who has opened these new fields of usefulness,
the peanut-raiser got $1.25 a bushel in 1917 instead of the 30 cents
that he got four years before.
It would be impossible to enumerate all the available sources of
vegetable oils, for all seeds and nuts contain more or less fatty matter
and as we become more economical we shall utilize of what we now throw
away. The germ of the corn kernel, once discarded in the manufacture of
starch, now yields a popular table oil. From tomato seeds, one of the
waste products of the canning factory, can be extracted 22 per cent. of
an edible oil. Oats contain 7 per cent. of oil. From rape seed the
Japanese get 20,000 tons of oil a year. To the sources previously
mentioned may be added pumpkin seeds, poppy seeds, raspberry seeds,
tobacco seeds, cockleburs, hazelnuts, walnuts, beechnuts and acorns.
The oil-bearing seeds of the tropics are innumerable and will become
increasingly essential to the inhabitants of northern lands. It was the
realization of this that brought on the struggle of the great powers
for the possession of tropical territory which, for years before, they
did not think worth while raising a flag over. No country in the future
can consider itself safe unless it has secure access to such sources. We
had a sharp lesson in this during the war. Palm oil, it seems, is
necessary for the manufacture of tinplate, an industry that was built up
in the United States by the McKinley tariff. The British possessions in
West Africa were the chief source of palm oil and the Germans had the
handling of it. During the war the British Government assumed control of
the palm oil products of the British and German colonies and prohibited
their export to other countries than England. Americans protested and
beseeched, but in vain. The British held, quite correctly, that they
needed all the oil they could get for food and lubrication and
nitroglycerin. But the British also needed canned meat from America for
their soldiers and when it was at length brought to their attention that
the packers could not ship meat unless they had cans and that cans could
not be made without tin and that tin could not be made without palm oil
the British Government consented to let us buy a little of their palm
oil. The lesson is that of Voltaire's story, "Candide," "Let us
cultivate our own garden"--and plant a few palm trees in it--also rubber
trees, but that is another story.
The international struggle for oil led to the partition of the Pacific
as the struggle for rubber led to the partition of Africa. Theodor
Weber, as Stevenson says, "harried the Samoans" to get copra much as
King Leopold of Belgium harried the Congoese to get caoutchouc. It was
Weber who first fully realized that the South Sea islands, formerly
given over to cannibals, pirates and missionaries, might be made
immensely valuable through the cultivation of the coconut palms. When
the ripe coconut is split open and exposed to the sun the meat dries up
and shrivels and in this form, called "copra," it can be cut out and
shipped to the factory where the oil is extracted and refined. Weber
while German Consul in Samoa was also manager of what was locally known
as "the long-handled concern" (_Deutsche Handels und Plantagen
Gesellschaft der Südsee Inseln zu Hamburg_), a pioneer commercial and
semi-official corporation that played a part in the Pacific somewhat
like the British Hudson Bay Company in Canada or East India Company in
Hindustan. Through the agency of this corporation on the start Germany
acquired a virtual monopoly of the transportation and refining of
coconut oil and would have become the dominant power in the Pacific if
she had not been checked by force of arms. In Apia Bay in 1889 and again
in Manila Bay in 1898 an American fleet faced a German fleet ready for
action while a British warship lay between. So we rescued the
Philippines and Samoa from German rule and in 1914 German power was
eliminated from the Pacific. During the ten years before the war, the
production of copra in the German islands more than doubled and this was
only the beginning of the business. Now these islands have been divided
up among Australia, New Zealand and Japan, and these countries are
planning to take care of the copra.
But although we get no extension of territory from the war we still
have the Philippines and some of the Samoan Islands, and these are
capable of great development. From her share of the Samoan Islands
Germany got a million dollars' worth of copra and we might get more from
ours. The Philippines now lead the world in the production of copra, but
Java is a close second and Ceylon not far behind. If we do not look out
we will be beaten both by the Dutch and the British, for they are
undertaking the cultivation of the coconut on a larger scale and in a
more systematic way. According to an official bulletin of the Philippine
Government a coconut plantation should bring in "dividends ranging from
10 to 75 per cent. from the tenth to the hundredth year." And this being
printed in 1913 figured the price of copra at 3-1/2 cents, whereas it
brought 4-1/2 cents in 1918, so the prospect is still more encouraging.
The copra is half fat and can be cheaply shipped to America, where it
can be crushed in the southern oilmills when they are not busy on
cottonseed or peanuts. But even this cost of transportation can be
reduced by extracting the oil in the islands and shipping it in bulk
like petroleum in tank steamers.
In the year ending June, 1918, the United States imported from the
Philippines 155,000,000 pounds of coconut oil worth $18,000,000 and
220,000,000 pounds of copra worth $10,000,000. But this was about half
our total importations; the rest of it we had to get from foreign
countries. Panama palms may give us a little relief from this dependence
on foreign sources. In 1917 we imported 19,000,000 whole coconuts from
Panama valued at $700,000.
[Illustration: SPLITTING COCONUTS ON THE ISLAND OF TAHITI
After drying in the sun the meat is picked and the oil extracted for
making coconut butter]
[Illustration: From "America's Munitions"
THE ELECTRIC CURRENT PASSING THROUGH SALT WATER IN THESE CELLS
DECOMPOSES THE SALT INTO CAUSTIC SODA AND CHLORINE GAS
There were eight rooms like this in the Edgewood plant, capable of
producing 200,000 pounds of chlorine a day]
A new form of fat that has rapidly come into our market is the oil of
the soya or soy bean. In 1918 we imported over 300,000,000 pounds of
soy-bean oil, mostly from Manchuria. The oil is used in manufacture of
substitutes for butter, lard, cheese, milk and cream, as well as for
soap and paint. The soy-bean can be raised in the United States wherever
corn can be grown and provides provender for man and beast. The soy meal
left after the extraction of the oil makes a good cattle food and the
fermented juice affords the shoya sauce made familiar to us through the
popularity of the chop-suey restaurants.
As meat and dairy products become scarcer and dearer we shall become
increasingly dependent upon the vegetable fats. We should therefore
devise means of saving what we now throw away, raise as much as we can
under our own flag, keep open avenues for our foreign supply and
encourage our cooks to make use of the new products invented by our
chemists.
CHAPTER XII
FIGHTING WITH FUMES
The Germans opened the war using projectiles seventeen inches in
diameter. They closed it using projectiles one one-hundred millionth of
an inch in diameter. And the latter were more effective than the former.
As the dimensions were reduced from molar to molecular the battle became
more intense. For when the Big Bertha had shot its bolt, that was the
end of it. Whomever it hit was hurt, but after that the steel fragments
of the shell lay on the ground harmless and inert. The men in the
dugouts could hear the shells whistle overhead without alarm. But the
poison gas could penetrate where the rifle ball could not. The malignant
molecules seemed to search out their victims. They crept through the
crevices of the subterranean shelters. They hunted for the pinholes in
the face masks. They lay in wait for days in the trenches for the
soldiers' return as a cat watches at the hole of a mouse. The cannon
ball could be seen and heard. The poison gas was invisible and
inaudible, and sometimes even the chemical sense which nature has given
man for his protection, the sense of smell, failed to give warning of
the approach of the foe.
The smaller the matter that man can deal with the more he can get out of
it. So long as man was dependent for power upon wind and water his
working capacity was very limited. But as soon as he passed over the
border line from physics into chemistry and learned how to use the
molecule, his efficiency in work and warfare was multiplied manifold.
The molecular bombardment of the piston by steam or the gases of
combustion runs his engines and propels his cars. The first man who
wanted to kill another from a safe distance threw the stone by his arm's
strength. David added to his arm the centrifugal force of a sling when
he slew Goliath. The Romans improved on this by concentrating in a
catapult the strength of a score of slaves and casting stone cannon
balls to the top of the city wall. But finally man got closer to
nature's secret and discovered that by loosing a swarm of gaseous
molecules he could throw his projectile seventy-five miles and then by
the same force burst it into flying fragments. There is no smaller
projectile than the atom unless our belligerent chemists can find a way
of using the electron stream of the cathode ray. But this so far has
figured only in the pages of our scientific romancers and has not yet
appeared on the battlefield. If, however, man could tap the reservoir of
sub-atomic energy he need do no more work and would make no more war,
for unlimited powers of construction and destruction would be at his
command. The forces of the infinitesimal are infinite.
The reason why a gas is so active is because it is so egoistic.
Psychologically interpreted, a gas consists of particles having the
utmost aversion to one another. Each tries to get as far away from every
other as it can. There is no cohesive force; no attractive impulse;
nothing to draw them together except the all too feeble power of
gravitation. The hotter they get the more they try to disperse and so
the gas expands. The gas represents the extreme of individualism as
steel represents the extreme of collectivism. The combination of the two
works wonders. A hot gas in a steel cylinder is the most powerful agency
known to man, and by means of it he accomplishes his greatest
achievements in peace or war time.
The projectile is thrown from the gun by the expansive force of the
gases released from the powder and when it reaches its destination it is
blown to pieces by the same force. This is the end of it if it is a
shell of the old-fashioned sort, for the gases of combustion mingle
harmlessly with the air of which they are normal constituents. But if it
is a poison gas shell each molecule as it is released goes off straight
into the air with a speed twice that of the cannon ball and carries
death with it. A man may be hit by a heavy piece of lead or iron and
still survive, but an unweighable amount of lethal gas may be fatal to
him.
Most of the novelties of the war were merely extensions of what was
already known. To increase the caliber of a cannon from 38 to 42
centimeters or its range from 30 to 75 miles does indeed make necessary
a decided change in tactics, but it is not comparable to the revolution
effected by the introduction of new weapons of unprecedented power such
as airplanes, submarines, tanks, high explosives or poison gas. If any
army had been as well equipped with these in the beginning as all armies
were at the end it might easily have won the war. That is to say, if the
general staff of any of the powers had had the foresight and confidence
to develop and practise these modes of warfare on a large scale in
advance it would have been irresistible against an enemy unprepared to
meet them. But no military genius appeared on either side with
sufficient courage and imagination to work out such schemes in secret
before trying them out on a small scale in the open. Consequently the
enemy had fair warning and ample time to learn how to meet them and
methods of defense developed concurrently with methods of attack. For
instance, consider the motor fortresses to which Ludendorff ascribes his
defeat. The British first sent out a few clumsy tanks against the German
lines. Then they set about making a lot of stronger and livelier ones,
but by the time these were ready the Germans had field guns to smash
them and chain fences with concrete posts to stop them. On the other
hand, if the Germans had followed up their advantage when they first set
the cloud of chlorine floating over the battlefield of Ypres they might
have won the war in the spring of 1915 instead of losing it in the fall
of 1918. For the British were unprepared and unprotected against the
silent death that swept down upon them on the 22nd of April, 1915. What
happened then is best told by Sir Arthur Conan Doyle in his "History of
the Great War."
From the base of the German trenches over a considerable length
there appeared jets of whitish vapor, which gathered and
swirled until they settled into a definite low cloud-bank,
greenish-brown below and yellow above, where it reflected the
rays of the sinking sun. This ominous bank of vapor, impelled
by a northern breeze, drifted swiftly across the space which
separated the two lines. The French troops, staring over the
top of their parapet at this curious screen which ensured them
a temporary relief from fire, were observed suddenly to throw
up their hands, to clutch at their throats, and to fall to the
ground in the agonies of asphyxiation. Many lay where they had
fallen, while their comrades, absolutely helpless against this
diabolical agency, rushed madly out of the mephitic mist and
made for the rear, over-running the lines of trenches behind
them. Many of them never halted until they had reached Ypres,
while others rushed westwards and put the canal between
themselves and the enemy. The Germans, meanwhile, advanced, and
took possession of the successive lines of trenches, tenanted
only by the dead garrisons, whose blackened faces, contorted
figures, and lips fringed with the blood and foam from their
bursting lungs, showed the agonies in which they had died. Some
thousands of stupefied prisoners, eight batteries of French
field-guns, and four British 4.7's, which had been placed in a
wood behind the French position, were the trophies won by this
disgraceful victory.
Under the shattering blow which they had received, a blow
particularly demoralizing to African troops, with their fears
of magic and the unknown, it was impossible to rally them
effectually until the next day. It is to be remembered in
explanation of this disorganization that it was the first
experience of these poison tactics, and that the troops engaged
received the gas in a very much more severe form than our own
men on the right of Langemarck. For a time there was a gap five
miles broad in the front of the position of the Allies, and
there were many hours during which there was no substantial
force between the Germans and Ypres. They wasted their time,
however, in consolidating their ground, and the chance of a
great coup passed forever. They had sold their souls as
soldiers, but the Devil's price was a poor one. Had they had a
corps of cavalry ready, and pushed them through the gap, it
would have been the most dangerous moment of the war.
A deserter had come over from the German side a week before and told
them that cylinders of poison gas had been laid in the front trenches,
but no one believed him or paid any attention to his tale. War was then,
in the Englishman's opinion, a gentleman's game, the royal sport, and
poison was prohibited by the Hague rules. But the Germans were not
playing the game according to the rules, so the British soldiers were
strangled in their own trenches and fell easy victims to the advancing
foe. Within half an hour after the gas was turned on 80 per cent. of the
opposing troops were knocked out. The Canadians, with wet handkerchiefs
over their faces, closed in to stop the gap, but if the Germans had been
prepared for such success they could have cleared the way to the coast.
But after such trials the Germans stopped the use of free chlorine and
began the preparation of more poisonous gases. In some way that may not
be revealed till the secret history of the war is published, the British
Intelligence Department obtained a copy of the lecture notes of the
instructions to the German staff giving details of the new system of gas
warfare to be started in December. Among the compounds named was
phosgene, a gas so lethal that one part in ten thousand of air may be
fatal. The antidote for it is hexamethylene tetramine. This is not
something the soldier--or anybody else--is accustomed to carry around
with him, but the British having had a chance to cram up in advance on
the stolen lecture notes were ready with gas helmets soaked in the
reagent with the long name.
The Germans rejoiced when gas bombs took the place of bayonets because
this was a field in which intelligence counted for more than brute
force and in which therefore they expected to be supreme. As usual they
were right in their major premise but wrong in their conclusion, owing
to the egoism of their implicit minor premise. It does indeed give the
advantage to skill and science, but the Germans were beaten at their own
game, for by the end of the war the United States was able to turn out
toxic gases at a rate of 200 tons a day, while the output of Germany or
England was only about 30 tons. A gas plant was started at Edgewood,
Maryland, in November, 1917. By March it was filling shell and before
the war put a stop to its activities in the fall it was producing
1,300,000 pounds of chlorine, 1,000,000 pounds of chlorpicrin, 1,300,000
pounds of phosgene and 700,000 pounds of mustard gas a month.
Chlorine, the first gas used, is unpleasantly familiar to every one who
has entered a chemical laboratory or who has smelled the breath of
bleaching powder. It is a greenish-yellow gas made from common salt. The
Germans employed it at Ypres by laying cylinders of the liquefied gas in
the trenches, about a yard apart, and running a lead discharge pipe over
the parapet. When the stop cocks are turned the gas streams out and
since it is two and a half times as heavy as air it rolls over the
ground like a noisome mist. It works best when the ground slopes gently
down toward the enemy and when the wind blows in that direction at a
rate between four and twelve miles an hour. But the wind, being strictly
neutral, may change its direction without warning and then the gases
turn back in their flight and attack their own side, something that
rifle bullets have never been known to do.
[Illustration: © International Film Service
GERMANS STARTING A GAS ATTACK ON THE RUSSIAN LINES
Behind the cylinders from which the gas streams are seen three lines of
German troops waiting to attack. The photograph was taken from above by
a Russian airman]
[Illustration: © Press Illustrating Service
FILLING THE CANNISTERS OF GAS MASKS WITH CHARCOAL MADE FROM FRUIT PITS
IN LONG ISLAND CITY]
Because free chlorine would not stay put and was dependent on the favor
of the wind for its effect, it was later employed, not as an elemental
gas, but in some volatile liquid that could be fired in a shell and so
released at any particular point far back of the front trenches.
The most commonly used of these compounds was phosgene, which, as the
reader can see by inspection of its formula, COCl_{2}, consists of
chlorine (Cl) combined with carbon monoxide (CO), the cause of deaths
from illuminating gas. These two poisonous gases, chlorine and carbon
monoxide, when mixed together, will not readily unite, but if a ray of
sunlight falls upon the mixture they combine at once. For this reason
John Davy, who discovered the compound over a hundred years ago, named
it phosgene, that is, "produced by light." The same roots recur in
hydrogen, so named because it is "produced from water," and phosphorus,
because it is a "light-bearer."
In its modern manufacture the catalyzer or instigator of the combination
is not sunlight but porous carbon. This is packed in iron boxes eight
feet long, through which the mixture of the two gases was forced. Carbon
monoxide may be made by burning coke with a supply of air insufficient
for complete combustion, but in order to get the pure gas necessary for
the phosgene common air was not used, but instead pure oxygen extracted
from it by a liquid air plant.
Phosgene is a gas that may be condensed easily to a liquid by cooling it
down to 46 degrees Fahrenheit. A mixture of three-quarters chlorine with
one-quarter phosgene has been found most effective. By itself phosgene
has an inoffensive odor somewhat like green corn and so may fail to
arouse apprehension until a toxic concentration is reached. But even
small doses have such an effect upon the heart action for days afterward
that a slight exertion may prove fatal.
The compound manufactured in largest amount in America was chlorpicrin.
This, like the others, is not so unfamiliar as it seems. As may be seen
from its formula, CCl_{3}NO_{2}, it is formed by joining the nitric acid
radical (NO_{2}), found in all explosives, with the main part of
chloroform (HCCl_{3}). This is not quite so poisonous as phosgene, but
it has the advantage that it causes nausea and vomiting. The soldier so
affected is forced to take off his gas mask and then may fall victim to
more toxic gases sent over simultaneously.
Chlorpicrin is a liquid and is commonly loaded in a shell or bomb with
20 per cent. of tin chloride, which produces dense white fumes that go
through gas masks. It is made from picric acid (trinitrophenol), one of
the best known of the high explosives, by treatment with chlorine. The
chlorine is obtained, as it is in the household, from common bleaching
powder, or "chloride of lime." This is mixed with water to form a cream
in a steel still 18 feet high and 8 feet in diameter. A solution of
calcium picrate, that is, the lime salt of picric acid, is pumped in and
as the reaction begins the mixture heats up and the chlorpicrin distils
over with the steam. When the distillate is condensed the chlorpicrin,
being the heavier liquid, settles out under the layer of water and may
be drawn off to fill the shell.
Much of what a student learns in the chemical laboratory he is apt to
forget in later life if he does not follow it up. But there are two
gases that he always remembers, chlorine and hydrogen sulfide. He is
lucky if he has escaped being choked by the former or sickened by the
latter. He can imagine what the effect would be if two offensive fumes
could be combined without losing their offensive features. Now a
combination something like this is the so-called mustard gas, which is
not a gas and is not made from mustard. But it is easily gasified, and
oil of mustard is about as near as Nature dare come to making such
sinful stuff. It was first made by Guthrie, an Englishman, in 1860, and
rediscovered by a German chemist, Victor Meyer, in 1886, but he found it
so dangerous to work with that he abandoned the investigation. Nobody
else cared to take it up, for nobody could see any use for it. So it
remained in innocuous desuetude, a mere name in "Beilstein's
Dictionary," together with the thousands of other organic compounds that
have been invented and never utilized. But on July 12, 1917, the British
holding the line at Ypres were besprinkled with this villainous
substance. Its success was so great that the Germans henceforth made it
their main reliance and soon the Allies followed suit. In one offensive
of ten days the Germans are said to have used a million shells
containing 2500 tons of mustard gas.
The making of so dangerous a compound on a large scale was one of the
most difficult tasks set before the chemists of this and other
countries, yet it was successfully solved. The raw materials are
chlorine, alcohol and sulfur. The alcohol is passed with steam through
a vertical iron tube filled with kaolin and heated. This converts the
alcohol into a gas known as ethylene (C_{2}H_{4}). Passing a stream of
chlorine gas into a tank of melted sulfur produces sulfur monochloride
and this treated with the ethylene makes the "mustard." The final
reaction was carried on at the Edgewood Arsenal in seven airtight tanks
or "reactors," each having a capacity of 30,000 pounds. The ethylene gas
being led into the tank and distributed through the liquid sulfur
chloride by porous blocks or fine nozzles, the two chemicals combined to
form what is officially named "di-chlor-di-ethyl-sulfide"
(ClC_{2}H_{4}SC_{2}H_{4}Cl). This, however, is too big a mouthful, so
even the chemists were glad to fall in with the commonalty and call it
"mustard gas."
The effectiveness of "mustard" depends upon its persistence. It is a
stable liquid, evaporating slowly and not easily decomposed. It lingers
about trenches and dugouts and impregnates soil and cloth for days. Gas
masks do not afford complete protection, for even if they are
impenetrable they must be taken off some time and the gas lies in wait
for that time. In some cases the masks were worn continuously for twelve
hours after the attack, but when they were removed the soldiers were
overpowered by the poison. A place may seem to be free from it but when
the sun heats up the ground the liquid volatilizes and the vapor soaks
through the clothing. As the men become warmed up by work their skin is
blistered, especially under the armpits. The mustard acts like steam,
producing burns that range from a mere reddening to serious
ulcerations, always painful and incapacitating, but if treated promptly
in the hospital rarely causing death or permanent scars. The gas attacks
the eyes, throat, nose and lungs and may lead to bronchitis or
pneumonia. It was found necessary at the front to put all the clothing
of the soldiers into the sterilizing ovens every night to remove all
traces of mustard. General Johnson and his staff in the 77th Division
were poisoned in their dugouts because they tried to alleviate the
discomfort of their camp cots by bedding taken from a neighboring
village that had been shelled the day before.
Of the 925 cases requiring medical attention at the Edgewood Arsenal 674
were due to mustard. During the month of August 3-1/2 per cent. of the
mustard plant force were sent to the hospital each day on the average.
But the record of the Edgewood Arsenal is a striking demonstration of
what can be done in the prevention of industrial accidents by the
exercise of scientific prudence. In spite of the fact that from three to
eleven thousand men were employed at the plant for the year 1918 and
turned out some twenty thousand tons of the most poisonous gases known
to man, there were only three fatalities and not a single case of
blindness.
Besides the four toxic gases previously described, chlorine, phosgene,
chlorpicrin and mustard, various other compounds have been and many
others might be made. A list of those employed in the present war
enumerates thirty, among them compounds of bromine, arsenic and cyanogen
that may prove more formidable than any so far used. American chemists
kept very mum during the war but occasionally one could not refrain
from saying: "If the Kaiser knew what I know he would surrender
unconditionally by telegraph." No doubt the science of chemical warfare
is in its infancy and every foresighted power has concealed weapons of
its own in reserve. One deadly compound, whose identity has not yet been
disclosed, is known as "Lewisite," from Professor Lewis of Northwestern,
who was manufacturing it at the rate of ten tons a day in the "Mouse
Trap" stockade near Cleveland.
Throughout the history of warfare the art of defense has kept pace with
the art of offense and the courage of man has never failed, no matter to
what new danger he was exposed. As each new gas employed by the enemy
was detected it became the business of our chemists to discover some
method of absorbing or neutralizing it. Porous charcoal, best made from
such dense wood as coconut shells, was packed in the respirator box
together with layers of such chemicals as will catch the gases to be
expected. Charcoal absorbs large quantities of any gas. Soda lime and
potassium permanganate and nickel salts were among the neutralizers
used.
The mask is fitted tightly about the face or over the head with rubber.
The nostrils are kept closed with a clip so breathing must be done
through the mouth and no air can be inhaled except that passing through
the absorbent cylinder. Men within five miles of the front were required
to wear the masks slung on their chests so they could be put on within
six seconds. A well-made mask with a fresh box afforded almost complete
immunity for a time and the soldiers learned within a few days to
handle their masks adroitly. So the problem of defense against this new
offensive was solved satisfactorily, while no such adequate protection
against the older weapons of bayonet and shrapnel has yet been devised.
Then the problem of the offense was to catch the opponent with his
mask off or to make him take it off. Here the lachrymators and
the sternutators, the tear gases and the sneeze gases, came into
play. Phenylcarbylamine chloride would make the bravest soldier
weep on the battlefield with the abandonment of a Greek hero.
Di-phenyl-chloro-arsine would set him sneezing. The Germans alternated
these with diabolical ingenuity so as to catch us unawares. Some shells
gave off voluminous smoke or a vile stench without doing much harm, but
by the time our men got used to these and grew careless about their
masks a few shells of some extremely poisonous gas were mixed with them.
The ideal gas for belligerent purposes would be odorless, colorless and
invisible, toxic even when diluted by a million parts of air, not set on
fire or exploded by the detonator of the shell, not decomposed by water,
not readily absorbed, stable enough to stand storage for six months and
capable of being manufactured by the thousands of tons. No one gas will
serve all aims. For instance, phosgene being very volatile and quickly
dissipated is thrown into trenches that are soon to be taken while
mustard gas being very tenacious could not be employed in such a case
for the trenches could not be occupied if they were captured.
The extensive use of poison gas in warfare by all the belligerents is a
vindication of the American protest at the Hague Conference against its
prohibition. At the First Conference of 1899 Captain Mahan argued very
sensibly that gas shells were no worse than other projectiles and might
indeed prove more merciful and that it was illogical to prohibit a
weapon merely because of its novelty. The British delegates voted with
the Americans in opposition to the clause "the contracting parties agree
to abstain from the use of projectiles the sole object of which is the
diffusion of asphyxiating or deleterious gases." But both Great Britain
and Germany later agreed to the provision. The use of poison gas by
Germany without warning was therefore an act of treachery and a
violation of her pledge, but the United States has consistently refused
to bind herself to any such restriction. The facts reported by General
Amos A. Fries, in command of the overseas branch of the American
Chemical Warfare Service, give ample support to the American contention
at The Hague:
Out of 1000 gas casualties there are from 30 to 40 fatalities,
while out of 1000 high explosive casualties the number of
fatalities run from 200 to 250. While exact figures are as yet
not available concerning the men permanently crippled or
blinded by high explosives one has only to witness the
debarkation of a shipload of troops to be convinced that the
number is very large. On the other hand there is, so far as
known at present, not a single case of permanent disability or
blindness among our troops due to gas and this in face of the
fact that the Germans used relatively large quantities of this
material.
In the light of these facts the prejudice against the use of
gas must gradually give way; for the statement made to the
effect that its use is contrary to the principles of humanity
will apply with far greater force to the use of high
explosives. As a matter of fact, for certain purposes toxic gas
is an ideal agent. For example, it is difficult to imagine any
agent more effective or more humane that may be used to render
an opposing battery ineffective or to protect retreating
troops.
Captain Mahan's argument at The Hague against the proposed prohibition
of poison gas is so cogent and well expressed that it has been quoted in
treatises on international law ever since. These reasons were, briefly:
1. That no shell emitting such gases is as yet in practical use
or has undergone adequate experiment; consequently, a vote
taken now would be taken in ignorance of the facts as to
whether the results would be of a decisive character or whether
injury in excess of that necessary to attain the end of
warfare--the immediate disabling of the enemy--would be
inflicted.
2. That the reproach of cruelty and perfidy, addressed against
these supposed shells, was equally uttered formerly against
firearms and torpedoes, both of which are now employed without
scruple. Until we know the effects of such asphyxiating shells,
there was no saying whether they would be more or less merciful
than missiles now permitted. That it was illogical, and not
demonstrably humane, to be tender about asphyxiating men with
gas, when all are prepared to admit that it was allowable to
blow the bottom out of an ironclad at midnight, throwing four
or five hundred into the sea, to be choked by water, with
scarcely the remotest chance of escape.
As Captain Mahan says, the same objection has been raised at the
introduction of each new weapon of war, even though it proved to be no
more cruel than the old. The modern rifle ball, swift and small and
sterilized by heat, does not make so bad a wound as the ancient sword
and spear, but we all remember how gunpowder was regarded by the dandies
of Hotspur's time:
And it was great pity, so it was,
This villainous saltpeter should be digg'd
Out of the bowels of the harmless earth
Which many a good tall fellow had destroy'd
So cowardly; and but for these vile guns
He would himself have been a soldier.
The real reason for the instinctive aversion manifested against any new
arm or mode of attack is that it reveals to us the intrinsic horror of
war. We naturally revolt against premeditated homicide, but we have
become so accustomed to the sword and latterly to the rifle that they do
not shock us as they ought when we think of what they are made for. The
Constitution of the United States prohibits the infliction of "cruel and
unusual punishments." The two adjectives were apparently used almost
synonymously, as though any "unusual" punishment were necessarily
"cruel," and so indeed it strikes us. But our ingenious lawyers were
able to persuade the courts that electrocution, though unknown to the
Fathers and undeniably "unusual," was not unconstitutional. Dumdum
bullets are rightfully ruled out because they inflict frightful and
often incurable wounds, and the aim of humane warfare is to disable the
enemy, not permanently to injure him.
[Illustration: From "America's Munitions" THE CHLORPICRIN PLANT AT THE
EDGEWOOD ARSENAL
From these stills, filled with a mixture of bleaching powder, lime, and
picric acid, the poisonous gas, chlorpicrin, distills off. This plant
produced 31 tons in one day]
[Illustration: Courtesy of the Metal and Thermit Corporation, N.Y.
REPAIRING THE BROKEN STERN POST OF THE U.S.S. NORTHERN PACIFIC, THE
BIGGEST MARINE WELD IN THE WORLD
On the right the fractured stern post is shown. On the left it is being
mended by means of thermit. Two crucibles each containing 700 pounds of
the thermit mixture are seen on the sides of the vessel. From the bottom
of these the melted steel flowed down to fill the fracture]
In spite of the opposition of the American and British delegates the
First Hague Conference adopted the clause, "The contracting powers agree
to abstain from the use of projectiles the [sole] object of which is the
diffusion of asphyxiating or deleterious gases." The word "sole"
(_unique_) which appears in the original French text of The Hague
convention is left out of the official English translation. This is a
strange omission considering that the French and British defended their
use of explosives which diffuse asphyxiating and deleterious gases on
the ground that this was not the "sole" purpose of the bombs but merely
an accidental effect of the nitric powder used.
The Hague Congress of 1907 placed in its rules for war: "It is expressly
forbidden to employ poisons or poisonous weapons." But such attempts to
rule out new and more effective means of warfare are likely to prove
futile in any serious conflict and the restriction gives the advantage
to the most unscrupulous side. We Americans, if ever we give our assent
to such an agreement, would of course keep it, but our enemy--whoever he
may be in the future--will be, as he always has been, utterly without
principle and will not hesitate to employ any weapon against us.
Besides, as the Germans held, chemical warfare favors the army that is
most intelligent, resourceful and disciplined and the nation that stands
highest in science and industry. This advantage, let us hope, will be on
our side.
CHAPTER XIII
PRODUCTS OF THE ELECTRIC FURNACE
The control of man over the materials of nature has been vastly enhanced
by the recent extension of the range of temperature at his command. When
Fahrenheit stuck the bulb of his thermometer into a mixture of snow and
salt he thought he had reached the nadir of temperature, so he scratched
a mark on the tube where the mercury stood and called it zero. But we
know that absolute zero, the total absence of heat, is 459 of
Fahrenheit's degrees lower than his zero point. The modern scientist can
get close to that lowest limit by making use of the cooling by the
expansion principle. He first liquefies air under pressure and then
releasing the pressure allows it to boil off. A tube of hydrogen
immersed in the liquid air as it evaporates is cooled down until it can
be liquefied. Then the boiling hydrogen is used to liquefy helium, and
as this boils off it lowers the temperature to within three or four
degrees of absolute zero.
The early metallurgist had no hotter a fire than he could make by
blowing charcoal with a bellows. This was barely enough for the smelting
of iron. But by the bringing of two carbon rods together, as in the
electric arc light, we can get enough heat to volatilize the carbon at
the tips, and this means over 7000 degrees Fahrenheit. By putting a
pressure of twenty atmospheres onto the arc light we can raise it to
perhaps 14,000 degrees, which is 3000 degrees hotter than the sun. This
gives the modern man a working range of about 14,500 degrees, so it is
no wonder that he can perform miracles.
When a builder wants to make an old house over into a new one he takes
it apart brick by brick and stone by stone, then he puts them together
in such new fashion as he likes. The electric furnace enables the
chemist to take his materials apart in the same way. As the temperature
rises the chemical and physical forces that hold a body together
gradually weaken. First the solid loosens up and becomes a liquid, then
this breaks bonds and becomes a gas. Compounds break up into their
elements. The elemental molecules break up into their component atoms
and finally these begin to throw off corpuscles of negative electricity
eighteen hundred times smaller than the smallest atom. These electrons
appear to be the building stones of the universe. No indication of any
smaller units has been discovered, although we need not assume that in
the electron science has delivered, what has been called, its
"ultim-atom." The Greeks called the elemental particles of matter
"atoms" because they esteemed them "indivisible," but now in the light
of the X-ray we can witness the disintegration of the atom into
electrons. All the chemical and physical properties of matter, except
perhaps weight, seem to depend upon the number and movement of the
negative and positive electrons and by their rearrangement one element
may be transformed into another.
So the electric furnace, where the highest attainable temperature is
combined with the divisive and directive force of the current, is a
magical machine for accomplishment of the metamorphoses desired by the
creative chemist. A hundred years ago Davy, by dipping the poles of his
battery into melted soda lye, saw forming on one of them a shining
globule like quicksilver. It was the metal sodium, never before seen by
man. Nowadays this process of electrolysis (electric loosening) is
carried out daily by the ton at Niagara.
The reverse process, electro-synthesis (electric combining), is equally
simple and even more important. By passing a strong electric current
through a mixture of lime and coke the metal calcium disengages itself
from the oxygen of the lime and attaches itself to the carbon. Or, to
put it briefly,
CaO + 3C --> CaC_{2} + CO
lime coke calcium carbon
carbide monoxide
This reaction is of peculiar importance because it bridges the gulf
between the organic and inorganic worlds. It was formerly supposed that
the substances found in plants and animals, mostly complex compounds of
carbon, hydrogen and oxygen, could only be produced by "vital forces."
If this were true it meant that chemistry was limited to the mineral
kingdom and to the extraction of such carbon compounds as happened to
exist ready formed in the vegetable and animal kingdoms. But fortunately
this barrier to human achievement proved purely illusory. The organic
field, once man had broken into it, proved easier to work in than the
inorganic.
But it must be confessed that man is dreadfully clumsy about it yet. He
takes a thousand horsepower engine and an electric furnace at several
thousand degrees to get carbon into combination with hydrogen while the
little green leaf in the sunshine does it quietly without getting hot
about it. Evidently man is working as wastefully as when he used a
thousand slaves to drag a stone to the pyramid or burned down a house to
roast a pig. Not until his laboratory is as cool and calm and
comfortable as the forest and the field can the chemist call himself
completely successful.
But in spite of his clumsiness the chemist is actually making things
that he wants and cannot get elsewhere. The calcium carbide that he
manufactures from inorganic material serves as the raw material for
producing all sorts of organic compounds. The electric furnace was first
employed on a large scale by the Cowles Electric Smelting and Aluminum
Company at Cleveland in 1885. On the dump were found certain lumps of
porous gray stone which, dropped into water, gave off a gas that
exploded at touch of a match with a splendid bang and flare. This gas
was acetylene, and we can represent the reaction thus:
CaC_{2} + 2 H_{2}O --> C_{2}H_{2} + CaO_{2}H_{2}
calcium carbide _added_ to water _
gives_ acetylene _and_ slaked lime
We are all familiar with this reaction now, for it is acetylene that
gives the dazzling light of the automobiles and of the automatic signal
buoys of the seacoast. When burned with pure oxygen instead of air it
gives the hottest of chemical flames, hotter even than the oxy-hydrogen
blowpipe. For although a given weight of hydrogen will give off more
heat when it burns than carbon will, yet acetylene will give off more
heat than either of its elements or both of them when they are separate.
This is because acetylene has stored up heat in its formation instead of
giving it off as in most reactions, or to put it in chemical language,
acetylene is an endothermic compound. It has required energy to bring
the H and the C together, therefore it does not require energy to
separate them, but, on the contrary, energy is released when they are
separated. That is to say, acetylene is explosive not only when mixed
with air as coal gas is but by itself. Under a suitable impulse
acetylene will break up into its original carbon and hydrogen with great
violence. It explodes with twice as much force without air as ordinary
coal gas with air. It forms an explosive compound with copper, so it has
to be kept out of contact with brass tubes and stopcocks. But compressed
in steel cylinders and dissolved in acetone, it is safe and commonly
used for welding and melting. It is a marvelous though not an unusual
sight on city streets to see a man with blue glasses on cutting down
through a steel rail with an oxy-acetylene blowpipe as easily as a
carpenter saws off a board. With such a flame he can carve out a pattern
in a steel plate in a way that reminds me of the days when I used to
make brackets with a scroll saw out of cigar boxes. The torch will
travel through a steel plate an inch or two thick at a rate of six to
ten inches a minute.
[Illustration: Courtesy of the Carborundum Company, Niagara Falls
MAKING ALOXITE IN THE ELECTRIC FURNACES BY FUSING COKE AND BAUXITE
In the background are the circular furnaces. In the foreground are the
fused masses of the product]
[Illustration: Courtesy of the Carborundum Co., Niagara Falls
A BLOCK OF CARBORUNDUM CRYSTALS]
[Illustration: Courtesy of the Carborundum Co., Niagara Falls
MAKING CARBORUNDUM IN THE ELECTRIC FURNACE
At the end may be seen the attachments for the wires carrying the
electric current and on the side the flames from the burning carbon.]
The temperatures attainable with various fuels in the compound blowpipe
are said to be:
Acetylene with oxygen 7878° F.
Hydrogen with oxygen 6785° F.
Coal gas with oxygen 6575° F.
Gasoline with oxygen 5788° F.
If we compare the formula of acetylene, C_{2}H_{2} with that of
ethylene, C_{2}H_{4}, or with ethane, C_{2}H_{6}, we see that acetylene
could take on two or four more atoms. It is evidently what the chemists
call an "unsaturated" compound, one that has not reached its limit of
hydrogenation. It is therefore a very active and energetic compound,
ready to pick up on the slightest instigation hydrogen or oxygen or
chlorine or any other elements that happen to be handy. This is why it
is so useful as a starting point for synthetic chemistry.
To build up from this simple substance, acetylene, the higher compounds
of carbon and oxygen it is necessary to call in the aid of that
mysterious agency, the catalyst. Acetylene is not always acted upon by
water, as we know, for we see it bubbling up through the water when
prepared from the carbide. But if to the water be added a little acid
and a mercury salt, the acetylene gas will unite with the water forming
a new compound, acetaldehyde. We can show the change most simply in this
fashion:
C_{2}H_{2} + H_{2}O --> C_{2}H_{4}O
acetylene _added to_ water _forms_ acetaldehyde
Acetaldehyde is not of much importance in itself, but is useful as a
transition. If its vapor mixed with hydrogen is passed over finely
divided nickel, serving as a catalyst, the two unite and we have
alcohol, according to this reaction:
C_{2}H_{4}O + H_{2} --> C_{2}H_{6}O
acetaldehyde _added to_ hydrogen _forms_ alcohol
Alcohol we are all familiar with--some of us too familiar, but the
prohibition laws will correct that. The point to be noted is that the
alcohol we have made from such unpromising materials as limestone and
coal is exactly the same alcohol as is obtained by the fermentation of
fruits and grains by the yeast plant as in wine and beer. It is not a
substitute or imitation. It is not the wood spirits (methyl alcohol,
CH_{4}O), produced by the destructive distillation of wood, equally
serviceable as a solvent or fuel, but undrinkable and poisonous.
Now, as we all know, cider and wine when exposed to the air gradually
turn into vinegar, that is, by the growth of bacteria the alcohol is
oxidized to acetic acid. We can, if we like, dispense with the bacteria
and speed up the process by employing a catalyst. Acetaldehyde, which is
halfway between alcohol and acid, may also be easily oxidized to acetic
acid. The relationship is readily seen by this:
C{2}H_{6}O --> CC_{2}H_{4}O --> C_{2}H_{4}O_{3}
alcohol acetaldehyde acetic acid
Acetic acid, familiar to us in a diluted and flavored form as vinegar,
is when concentrated of great value in industry, especially as a
solvent. I have already referred to its use in combination with
cellulose as a "dope" for varnishing airplane canvas or making
non-inflammable film for motion pictures. Its combination with lime,
calcium acetate, when heated gives acetone, which, as may be seen from
its formula (C_{3}H_{6}O) is closely related to the other compounds we
have been considering, but it is neither an alcohol nor an acid. It is
extensively employed as a solvent.
Acetone is not only useful for dissolving solids but it will under
pressure dissolve many times its volume of gaseous acetylene. This is a
convenient way of transporting and handling acetylene for lighting or
welding.
If instead of simply mixing the acetone and acetylene in a solution we
combine them chemically we can get isoprene, which is the mother
substance of ordinary India rubber. From acetone also is made the "war
rubber" of the Germans (methyl rubber), which I have mentioned in a
previous chapter. The Germans had been getting about half their supply
of acetone from American acetate of lime and this was of course shut
off. That which was produced in Germany by the distillation of beech
wood was not even enough for the high explosives needed at the front. So
the Germans resorted to rotting potatoes--or rather let us say, since it
sounds better--to the cultivation of _Bacillus macerans_. This
particular bacillus converts the starch of the potato into two-thirds
alcohol and one-third acetone. But soon potatoes got too scarce to be
used up in this fashion, so the Germans turned to calcium carbide as a
source of acetone and before the war ended they had a factory capable of
manufacturing 2000 tons of methyl rubber a year. This shows the
advantage of having several strings to a bow.
The reason why acetylene is such an active and acquisitive thing the
chemist explains, or rather expresses, by picturing its structure in
this shape:
H-C[triple bond]C-H
Now the carbon atoms are holding each other's hands because they have
nothing else to do. There are no other elements around to hitch on to.
But the two carbons of acetylene readily loosen up and keeping the
connection between them by a single bond reach out in this fashion with
their two disengaged arms and grab whatever alien atoms happen to be in
the vicinity:
| |
H-C-C-H
| |
Carbon atoms belong to the quadrumani like the monkeys, so they are
peculiarly fitted to forming chains and rings. This accounts for the
variety and complexity of the carbon compounds.
So when acetylene gas mixed with other gases is passed over a catalyst,
such as a heated mass of iron ore or clay (hydrates or silicates of iron
or aluminum), it forms all sorts of curious combinations. In the
presence of steam we may get such simple compounds as acetic acid,
acetone and the like. But when three acetylene molecules join to form a
ring of six carbon atoms we get compounds of the benzene series such as
were described in the chapter on the coal-tar colors. If ammonia is
mixed with acetylene we may get rings with the nitrogen atom in place of
one of the carbons, like the pyridins and quinolins, pungent bases such
as are found in opium and tobacco. Or if hydrogen sulfide is mixed with
the acetylene we may get thiophenes, which have sulfur in the ring. So,
starting with the simple combination of two atoms of carbon with two of
hydrogen, we can get directly by this single process some of the most
complicated compounds of the organic world, as well as many others not
found in nature.
In the development of the electric furnace America played a pioneer
part. Provost Smith of the University of Pennsylvania, who is the best
authority on the history of chemistry in America, claims for Robert
Hare, a Philadelphia chemist born in 1781, the honor of constructing the
first electrical furnace. With this crude apparatus and with no greater
electromotive force than could be attained from a voltaic pile, he
converted charcoal into graphite, volatilized phosphorus from its
compounds, isolated metallic calcium and synthesized calcium carbide. It
is to Hare also that we owe the invention in 1801 of the oxy-hydrogen
blowpipe, which nowadays is used with acetylene as well as hydrogen.
With this instrument he was able to fuse strontia and volatilize
platinum.
But the electrical furnace could not be used on a commercial scale until
the dynamo replaced the battery as a source of electricity. The
industrial development of the electrical furnace centered about the
search for a cheap method of preparing aluminum. This is the metallic
base of clay and therefore is common enough. But clay, as we know from
its use in making porcelain, is very infusible and difficult to
decompose. Sixty years ago aluminum was priced at $140 a pound, but one
would have had difficulty in buying such a large quantity as a pound at
any price. At international expositions a small bar of it might be seen
in a case labeled "silver from clay." Mechanics were anxious to get the
new metal, for it was light and untarnishable, but the metallurgists
could not furnish it to them at a low enough price. In order to extract
it from clay a more active metal, sodium, was essential. But sodium also
was rare and expensive. In those days a professor of chemistry used to
keep a little stick of it in a bottle under kerosene and once a year he
whittled off a piece the size of a pea and threw it into water to show
the class how it sizzled and gave off hydrogen. The way to get cheaper
aluminum was, it seemed, to get cheaper sodium and Hamilton Young
Castner set himself at this problem. He was a Brooklyn boy, a student of
Chandler's at Columbia. You can see the bronze tablet in his honor at
the entrance of Havemeyer Hall. In 1886 he produced metallic sodium by
mixing caustic soda with iron and charcoal in an iron pot and heating in
a gas furnace. Before this experiment sodium sold at $2 a pound; after
it sodium sold at twenty cents a pound.
But although Castner had succeeded in his experiment he was defeated in
his object. For while he was perfecting the sodium process for making
aluminum the electrolytic process for getting aluminum directly was
discovered in Oberlin. So the $250,000 plant of the "Aluminium Company
Ltd." that Castner had got erected at Birmingham, England, did not make
aluminum at all, but produced sodium for other purposes instead. Castner
then turned his attention to the electrolytic method of producing sodium
by the use of the power of Niagara Falls, electric power. Here in 1894
he succeeded in separating common salt into its component elements,
chlorine and sodium, by passing the electric current through brine and
collecting the sodium in the mercury floor of the cell. The sodium by
the action of water goes into caustic soda. Nowadays sodium and chlorine
and their components are made in enormous quantities by the
decomposition of salt. The United States Government in 1918 procured
nearly 4,000,000 pounds of chlorine for gas warfare.
The discovery of the electrical process of making aluminum that
displaced the sodium method was due to Charles M. Hall. He was the son
of a Congregational minister and as a boy took a fancy to chemistry
through happening upon an old text-book of that science in his father's
library. He never knew who the author was, for the cover and title page
had been torn off. The obstacle in the way of the electrolytic
production of aluminum was, as I have said, because its compounds were
so hard to melt that the current could not pass through. In 1886, when
Hall was twenty-two, he solved the problem in the laboratory of Oberlin
College with no other apparatus than a small crucible, a gasoline burner
to heat it with and a galvanic battery to supply the electricity. He
found that a Greenland mineral, known as cryolite (a double fluoride of
sodium and aluminum), was readily fused and would dissolve alumina
(aluminum oxide). When an electric current was passed through the melted
mass the metal aluminum would collect at one of the poles.
In working out the process and defending his claims Hall used up all his
own money, his brother's and his uncle's, but he won out in the end and
Judge Taft held that his patent had priority over the French claim of
Hérault. On his death, a few years ago, Hall left his large fortune to
his Alma Mater, Oberlin.
Two other young men from Ohio, Alfred and Eugene Cowles, with whom Hall
was for a time associated, wore the first to develop the wide
possibilities of the electric furnace on a commercial scale. In 1885
they started the Cowles Electric Smelting and Aluminum Company at
Lockport, New York, using Niagara power. The various aluminum bronzes
made by absorbing the electrolyzed aluminum in copper attracted
immediate attention by their beauty and usefulness in electrical work
and later the company turned out other products besides aluminum, such
as calcium carbide, phosphorus, and carborundum. They got carborundum as
early as 1885 but miscalled it "crystallized silicon," so its
introduction was left to E.A. Acheson, who was a graduate of Edison's
laboratory. In 1891 he packed clay and charcoal into an iron bowl,
connected it to a dynamo and stuck into the mixture an electric light
carbon connected to the other pole of the dynamo. When he pulled out the
rod he found its end encrusted with glittering crystals of an unknown
substance. They were blue and black and iridescent, exceedingly hard and
very beautiful. He sold them at first by the carat at a rate that would
amount to $560 a pound. They were as well worth buying as diamond dust,
but those who purchased them must have regretted it, for much finer
crystals were soon on sale at ten cents a pound. The mysterious
substance turned out to be a compound of carbon and silicon, the
simplest possible compound, one atom of each, CSi. Acheson set up a
factory at Niagara, where he made it in ten-ton batches. The furnace
consisted simply of a brick box fifteen feet long and seven feet wide
and deep, with big carbon electrodes at the ends. Between them was
packed a mixture of coke to supply the carbon, sand to supply the
silicon, sawdust to make the mass porous and salt to make it fusible.
[Illustration: The first American electric furnace, constructed by
Robert Hare of Philadelphia. From "Chemistry in America," by Edgar Fahs
Smith]
The substance thus produced at Niagara Falls is known as "carborundum"
south of the American-Canadian boundary and as "crystolon" north of this
line, as "carbolon" by another firm, and as "silicon carbide" by
chemists the world over. Since it is next to the diamond in hardness it
takes off metal faster than emery (aluminum oxide), using less power and
wasting less heat in futile fireworks. It is used for grindstones of
all sizes, including those the dentist uses on your teeth. It has
revolutionized shop-practice, for articles can be ground into shape
better and quicker than they can be cut. What is more, the artificial
abrasives do not injure the lungs of the operatives like sandstone. The
output of artificial abrasives in the United States and Canada for 1917
was:
Tons Value
Silicon carbide 8,323 $1,074,152
Aluminum oxide 48,463 6,969,387
A new use for carborundum was found during the war when Uncle Sam
assumed the rôle of Jove as "cloud-compeller." Acting on carborundum
with chlorine--also, you remember, a product of electrical
dissolution--the chlorine displaces the carbon, forming silicon
tetra-chloride (SiCl_{4}), a colorless liquid resembling chloroform.
When this comes in contact with moist air it gives off thick, white
fumes, for water decomposes it, giving a white powder (silicon
hydroxide) and hydrochloric acid. If ammonia is present the acid will
unite with it, giving further white fumes of the salt, ammonium
chloride. So a mixture of two parts of silicon chloride with one part of
dry ammonia was used in the war to produce smoke-screens for the
concealment of the movements of troops, batteries and vessels or put in
shells so the outlook could see where they burst and so get the range.
Titanium tetra-chloride, a similar substance, proved 50 per cent. better
than silicon, but phosphorus--which also we get from the electric
furnace--was the most effective mistifier of all.
Before the introduction of the artificial abrasives fine grinding was
mostly done by emery, which is an impure form of aluminum oxide found in
nature. A purer form is made from the mineral bauxite by driving off its
combined water. Bauxite is the ore from which is made the pure aluminum
oxide used in the electric furnace for the production of metallic
aluminum. Formerly we imported a large part of our bauxite from France,
but when the war shut off this source we developed our domestic fields
in Arkansas, Alabama and Georgia, and these are now producing half a
million tons a year. Bauxite simply fused in the electric furnace makes
a better abrasive than the natural emery or corundum, and it is sold for
this purpose under the name of "aloxite," "alundum," "exolon," "lionite"
or "coralox." When the fused bauxite is worked up with a bonding
material into crucibles or muffles and baked in a kiln it forms the
alundum refractory ware. Since alundum is porous and not attacked by
acids it is used for filtering hot and corrosive liquids that would eat
up filter-paper. Carborundum or crystolon is also made up into
refractory ware for high temperature work. When the fused mass of the
carborundum furnace is broken up there is found surrounding the
carborundum core a similar substance though not quite so hard and
infusible, known as "carborundum sand" or "siloxicon." This is mixed
with fireclay and used for furnace linings.
Many new forms of refractories have come into use to meet the demands of
the new high temperature work. The essentials are that it should not
melt or crumble at high heat and should not expand and contract greatly
under changes of temperature (low coefficient of thermal expansion).
Whether it is desirable that it should heat through readily or slowly
(coefficient of thermal conductivity) depends on whether it is wanted as
a crucible or as a furnace lining. Lime (calcium oxide) fuses only at
the highest heat of the electric furnace, but it breaks down into dust.
Magnesia (magnesium oxide) is better and is most extensively employed.
For every ton of steel produced five pounds of magnesite is needed.
Formerly we imported 90 per cent. of our supply from Austria, but now we
get it from California and Washington. In 1913 the American production
of magnesite was only 9600 tons. In 1918 it was 225,000. Zirconia
(zirconium oxide) is still more refractory and in spite of its greater
cost zirkite is coming into use as a lining for electric furnaces.
Silicon is next to oxygen the commonest element in the world. It forms a
quarter of the earth's crust, yet it is unfamiliar to most of us. That
is because it is always found combined with oxygen in the form of silica
as quartz crystal or sand. This used to be considered too refractory to
be blown but is found to be easily manipulable at the high temperatures
now at the command of the glass-blower. So the chemist rejoices in
flasks that he can heat red hot in the Bunsen burner and then plunge
into ice water without breaking, and the cook can bake and serve in a
dish of "pyrex," which is 80 per cent. silica.
At the beginning of the twentieth century minute specimens of silicon
were sold as laboratory curiosities at the price of $100 an ounce. Two
years later it was turned out by the barrelful at Niagara as an
accidental by-product and could not find a market at ten cents a pound.
Silicon from the electric furnace appears in the form of hard,
glittering metallic crystals.
An alloy of iron and silicon, ferro-silicon, made by heating a mixture
of iron ore, sand and coke in the electrical furnace, is used as a
deoxidizing agent in the manufacture of steel.
Since silicon has been robbed with difficulty of its oxygen it takes it
on again with great avidity. This has been made use of in the making of
hydrogen. A mixture of silicon (or of the ferro-silicon alloy containing
90 per cent. of silicon) with soda and slaked lime is inert, compact and
can be transported to any point where hydrogen is needed, say at a
battle front. Then the "hydrogenite," as the mixture is named, is
ignited by a hot iron ball and goes off like thermit with the production
of great heat and the evolution of a vast volume of hydrogen gas. Or the
ferro-silicon may be simply burned in an atmosphere of steam in a closed
tank after ignition with a pinch of gunpowder. The iron and the silicon
revert to their oxides while the hydrogen of the water is set free. The
French "silikol" method consists in treating silicon with a 40 per cent.
solution of soda.
Another source of hydrogen originating with the electric furnace is
"hydrolith," which consists of calcium hydride. Metallic calcium is
prepared from lime in the electric furnace. Then pieces of the calcium
are spread out in an oven heated by electricity and a current of dry
hydrogen passed through. The gas is absorbed by the metal, forming the
hydride (CaH_{2}). This is packed up in cans and when hydrogen is
desired it is simply dropped into water, when it gives off the gas just
as calcium carbide gives off acetylene.
This last reaction was also used in Germany for filling Zeppelins. For
calcium carbide is convenient and portable and acetylene, when it is
once started, as by an electric shock, decomposes spontaneously by its
own internal heat into hydrogen and carbon. The latter is left as a
fine, pure lampblack, suitable for printer's ink.
Napoleon, who was always on the lookout for new inventions that could be
utilized for military purposes, seized immediately upon the balloon as
an observation station. Within a few years after the first ascent had
been made in Paris Napoleon took balloons and apparatus for generating
hydrogen with him on his "archeological expedition" to Egypt in which he
hoped to conquer Asia. But the British fleet in the Mediterranean put a
stop to this experiment by intercepting the ship, and military aviation
waited until the Great War for its full development. This caused a
sudden demand for immense quantities of hydrogen and all manner of means
was taken to get it. Water is easily decomposed into hydrogen and oxygen
by passing an electric current through it. In various electrolytical
processes hydrogen has been a wasted by-product since the balloon demand
was slight and it was more bother than it was worth to collect and
purify the hydrogen. Another way of getting hydrogen in quantity is by
passing steam over red-hot coke. This produces the blue water-gas, which
contains about 50 per cent. hydrogen, 40 per cent. carbon monoxide and
the rest nitrogen and carbon dioxide. The last is removed by running the
mixed gases through lime. Then the nitrogen and carbon monoxide are
frozen out in an air-liquefying apparatus and the hydrogen escapes to
the storage tank. The liquefied carbon monoxide, allowed to regain its
gaseous form, is used in an internal combustion engine to run the plant.
There are then many ways of producing hydrogen, but it is so light and
bulky that it is difficult to get it where it is wanted. The American
Government in the war made use of steel cylinders each holding 161 cubic
feet of the gas under a pressure of 2000 pounds per square inch. Even
the hydrogen used by the troops in France was shipped from America in
this form. For field use the ferro-silicon and soda process was adopted.
A portable generator of this type was capable of producing 10,000 cubic
feet of the gas per hour.
The discovery by a Kansas chemist of natural sources of helium may make
it possible to free ballooning of its great danger, for helium is
non-inflammable and almost as light as hydrogen.
Other uses of hydrogen besides ballooning have already been referred to
in other chapters. It is combined with nitrogen to form synthetic
ammonia. It is combined with oxygen in the oxy-hydrogen blowpipe to
produce heat. It is combined with vegetable and animal oils to convert
them into solid fats. There is also the possibility of using it as a
fuel in the internal combustion engine in place of gasoline, but for
this purpose we must find some way of getting hydrogen portable or
producible in a compact form.
Aluminum, like silicon, sodium and calcium, has been rescued by violence
from its attachment to oxygen and like these metals it reverts with
readiness to its former affinity. Dr. Goldschmidt made use of this
reaction in his thermit process. Powdered aluminum is mixed with iron
oxide (rust). If the mixture is heated at any point a furious struggle
takes place throughout the whole mass between the iron and the aluminum
as to which metal shall get the oxygen, and the aluminum always comes
out ahead. The temperature runs up to some 6000 degrees Fahrenheit
within thirty seconds and the freed iron, completely liquefied, runs
down into the bottom of the crucible, where it may be drawn off by
opening a trap door. The newly formed aluminum oxide (alumina) floats as
slag on top. The applications of the thermit process are innumerable.
If, for instance, it is desired to mend a broken rail or crank shaft
without moving it from its place, the two ends are brought together or
fixed at the proper distance apart. A crucible filled with the thermit
mixture is set up above the joint and the thermit ignited with a priming
of aluminum and barium peroxide to start it off. The barium peroxide
having a superabundance of oxygen gives it up readily and the aluminum
thus encouraged attacks the iron oxide and robs it of its oxygen. As
soon as the iron is melted it is run off through the bottom of the
crucible and fills the space between the rail ends, being kept from
spreading by a mold of refractory material such as magnesite. The two
ends of the rail are therefore joined by a section of the same size,
shape, substance and strength as themselves. The same process can be
used for mending a fracture or supplying a missing fragment of a steel
casting of any size, such as a ship's propeller or a cogwheel.
[Illustration: TYPES OF GAS MASK USED BY AMERICA, THE ALLIES, AND
GERMANY DURING THE WAR
In the top row are the American masks, chronologically, from left to
right: U.S. Navy mask (obsolete), U.S. Navy mask (final type), U.S. Army
box respirator (used throughout the war), U.S.R.F.K. respirator,
U.S.A.T. respirator (an all-rubber mask), U.S.K.T. respirator (a sewed
fabric mask), and U.S. "Model 1919," ready for production when the
armistice was signed. In the middle row, left to right, are: British
veil (the original emergency mask used in April, 1915), British P.H.
helmet (the next emergency mask), British box respirator (standard
British army type), French M2 mask (original type), French Tissot
artillery mask, and French A.R.S. mask (latest type). In the front row:
the latest German mask, the Russian mask, Italian mask, British motor
corps mask, U.S. rear area emergency respirator, and U.S. Connell mask]
[Illustration: PUMPING MELTED WHITE PHOSPHORUS INTO HAND GRENADES
FILLED WITH WATER--EDGEWOOD ARSENAL]
[Illustration: FILLING SHELL WITH "MUSTARD GAS"
Empty shells are being placed on small trucks to be run into the filling
chamber. The large truck in the foreground contains loaded shell]
For smaller work thermit has two rivals, the oxy-acetylene torch and
electric welding. The former has been described and the latter is rather
out of the range of this volume, although I may mention that in the
latter part of 1918 there was launched from a British shipyard the first
rivotless steel vessel. In this the steel plates forming the shell,
bulkheads and floors are welded instead of being fastened together by
rivets. There are three methods of doing this depending upon the
thickness of the plates and the sort of strain they are subject to. The
plates may be overlapped and tacked together at intervals by pressing
the two electrodes on opposite sides of the same point until the spot is
sufficiently heated to fuse together the plates here. Or roller
electrodes may be drawn slowly along the line of the desired weld,
fusing the plates together continuously as they go. Or, thirdly, the
plates may be butt-welded by being pushed together edge to edge without
overlapping and the electric current being passed from one plate to the
other heats up the joint where the conductivity is interrupted.
It will be observed that the thermit process is essentially like the
ordinary blast furnace process of smelting iron and other metals except
that aluminum is used instead of carbon to take the oxygen away from the
metal in the ore. This has an advantage in case carbon-free metals are
desired and the process is used for producing manganese, tungsten,
titanium, molybdenum, vanadium and their allows with iron and copper.
During the war thermit found a new and terrible employment, as it was
used by the airmen for setting buildings on fire and exploding
ammunition dumps. The German incendiary bombs consisted of a perforated
steel nose-piece, a tail to keep it falling straight and a cylindrical
body which contained a tube of thermit packed around with mineral wax
containing potassium perchlorate. The fuse was ignited as the missile
was released and the thermit, as it heated up, melted the wax and
allowed it to flow out together with the liquid iron through the holes
in the nose-piece. The American incendiary bombs were of a still more
malignant type. They weighed about forty pounds apiece and were charged
with oil emulsion, thermit and metallic sodium. Sodium decomposes water
so that if any attempt were made to put out with a hose a fire started
by one of these bombs the stream of water would be instantaneously
changed into a jet of blazing hydrogen.
Besides its use in combining and separating different elements the
electric furnace is able to change a single element into its various
forms. Carbon, for instance, is found in three very distinct forms: in
hard, transparent and colorless crystals as the diamond, in black,
opaque, metallic scales as graphite, and in shapeless masses and powder
as charcoal, coke, lampblack, and the like. In the intense heat of the
electric arc these forms are convertible one into the other according to
the conditions. Since the third form is the cheapest the object is to
change it into one of the other two. Graphite, plumbago or "blacklead,"
as it is still sometimes called, is not found in many places and more
rarely found pure. The supply was not equal to the demand until Acheson
worked out the process of making it by packing powdered anthracite
between the electrodes of his furnace. In this way graphite can be
cheaply produced in any desired quantity and quality.
Since graphite is infusible and incombustible except at exceedingly high
temperatures, it is extensively used for crucibles and electrodes. These
electrodes are made in all sizes for the various forms of electric lamps
and furnaces from rods one-sixteenth of an inch in diameter to bars a
foot thick and six feet long. It is graphite mixed with fine clay to
give it the desired degree of hardness that forms the filling of our
"lead" pencils. Finely ground and flocculent graphite treated with
tannin may be held in suspension in liquids and even pass through
filter-paper. The mixture with water is sold under the name of
"aquadag," with oil as "oildag" and with grease as "gredag," for
lubrication. The smooth, slippery scales of graphite in suspension slide
over each other easily and keep the bearings from rubbing against each
other.
The other and more difficult metamorphosis of carbon, the transformation
of charcoal into diamond, was successfully accomplished by Moissan in
1894. Henri Moissan was a toxicologist, that is to say, a Professor of
Poisoning, in the Paris School of Pharmacy, who took to experimenting
with the electric furnace in his leisure hours and did more to
demonstrate its possibilities than any other man. With it he isolated
fluorine, most active of the elements, and he prepared for the first
time in their purity many of the rare metals that have since found
industrial employment. He also made the carbides of the various metals,
including the now common calcium carbide. Among the problems that he
undertook and solved was the manufacture of artificial diamonds. He
first made pure charcoal by burning sugar. This was packed with iron in
the hollow of a block of lime into which extended from opposite sides
the carbon rods connected to the dynamo. When the iron had melted and
dissolved all the carbon it could, Moissan dumped it into water or
better into melted lead or into a hole in a copper block, for this
cooled it most rapidly. After a crust was formed it was left to solidify
slowly. The sudden cooling of the iron on the outside subjected the
carbon, which was held in solution, to intense pressure and when the bit
of iron was dissolved in acid some of the carbon was found to be
crystallized as diamond, although most of it was graphite. To be sure,
the diamonds were hardly big enough to be seen with the naked eye, but
since Moissan's aim was to make diamonds, not big diamonds, he ceased
his efforts at this point.
To produce large diamonds the carbon would have to be liquefied in
considerable quantity and kept in that state while it slowly
crystallized. But that could only be accomplished at a temperature and
pressure and duration unattainable as yet. Under ordinary atmospheric
pressure carbon passes over from the solid to the gaseous phase without
passing through the liquid, just as snow on a cold, clear day will
evaporate without melting.
Probably some one in the future will take up the problem where Moissan
dropped it and find out how to make diamonds of any size. But it is not
a question that greatly interests either the scientist or the
industrialist because there is not much to be learned from it and not
much to be made out of it. If the inventor of a process for making
cheap diamonds could keep his electric furnace secretly in his cellar
and market his diamonds cautiously he might get rich out of it, but he
would not dare to turn out very large stones or too many of them, for if
a suspicion got around that he was making them the price would fall to
almost nothing even if he did sell another one. For the high price of
the diamond is purely fictitious. It is in the first place kept up by
limiting the output of the natural stone by the combination of dealers
and, further, the diamond is valued not for its usefulness or beauty but
by its real or supposed rarity. Chesterton says: "All is gold that
glitters, for the glitter is the gold." This is not so true of gold, for
if gold were as cheap as nickel it would be very valuable, since we
should gold-plate our machinery, our ships, our bridges and our roofs.
But if diamonds were cheap they would be good for nothing except
grindstones and drills. An imitation diamond made of heavy glass (paste)
cannot be distinguished from the genuine gem except by an expert. It
sparkles about as brilliantly, for its refractive index is nearly as
high. The reason why it is not priced so highly is because the natural
stone has presumably been obtained through the toil and sweat of
hundreds of negroes searching in the blue ground of the Transvaal for
many months. It is valued exclusively by its cost. To wear a diamond
necklace is the same as hanging a certified check for $100,000 by a
string around the neck.
Real values are enhanced by reduction in the cost of the price of
production. Fictitious values are destroyed by it. Aluminum at
twenty-five cents a pound is immensely more valuable to the world than
when it is a curiosity in the chemist's cabinet and priced at $160 a
pound.
So the scope of the electric furnace reaches from the costly but
comparatively valueless diamond to the cheap but indispensable steel. As
F.J. Tone says, if the automobile manufacturers were deprived of Niagara
products, the abrasives, aluminum, acetylene for welding and high-speed
tool steel, a factory now turning out five hundred cars a day would be
reduced to one hundred. I have here been chiefly concerned with
electricity as effecting chemical changes in combining or separating
elements, but I must not omit to mention its rapidly extending use as a
source of heat, as in the production and casting of steel. In 1908 there
were only fifty-five tons of steel produced by the electric furnace in
the United States, but by 1918 this had risen to 511,364 tons. And
besides ordinary steel the electric furnace has given us alloys of iron
with the once "rare metals" that have created a new science of
metallurgy.
CHAPTER XIV
METALS, OLD AND NEW
The primitive metallurgist could only make use of such metals as he
found free in nature, that is, such as had not been attacked and
corroded by the ubiquitous oxygen. These were primarily gold or copper,
though possibly some original genius may have happened upon a bit of
meteoric iron and pounded it out into a sword. But when man found that
the red ocher he had hitherto used only as a cosmetic could be made to
yield iron by melting it with charcoal he opened a new era in
civilization, though doubtless the ocher artists of that day denounced
him as a utilitarian and deplored the decadence of the times.
Iron is one of the most timid of metals. It has a great disinclination
to be alone. It is also one of the most altruistic of the elements. It
likes almost every other element better than itself. It has an especial
affection for oxygen, and, since this is in both air and water, and
these are everywhere, iron is not long without a mate. The result of
this union goes by various names in the mineralogical and chemical
worlds, but in common language, which is quite good enough for our
purpose, it is called iron rust.
[Illustration: By courtesy _Mineral Foote-Notes_.
From Agricola's "De Re Metallica 1550." Primitive furnace for smelting
iron ore.]
Not many of us have ever seen iron, the pure metal, soft, ductile and
white like silver. As soon as it is exposed to the air it veils itself
with a thin film of rust and becomes black and then red. For that reason
there is practically no iron in the world except what man has made. It
is rarer than gold, than diamonds; we find in the earth no nuggets or
crystals of it the size of the fist as we find of these. But
occasionally there fall down upon us out of the clear sky great chunks
of it weighing tons. These meteorites are the mavericks of the universe.
We do not know where they come from or what sun or planet they belonged
to. They are our only visitors from space, and if all the other spheres
are like these fragments we know we are alone in the universe. For they
contain rustless iron, and where iron does not rust man cannot live, nor
can any other animal or any plant.
Iron rusts for the same reason that a stone rolls down hill, because it
gets rid of its energy that way. All things in the universe are
constantly trying to get rid of energy except man, who is always trying
to get more of it. Or, on second thought, we see that man is the
greatest spendthrift of all, for he wants to expend so much more energy
than he has that he borrows from the winds, the streams and the coal in
the rocks. He robs minerals and plants of the energy which they have
stored up to spend for their own purposes, just as he robs the bee of
its honey and the silk worm of its cocoon.
Man's chief business is in reversing the processes of nature. That is
the way he gets his living. And one of his greatest triumphs was when he
discovered how to undo iron rust and get the metal out of it. In the
four thousand years since he first did this he has accomplished more
than in the millions of years before. Without knowing the value of iron
rust man could attain only to the culture of the Aztecs and Incas, the
ancient Egyptians and Assyrians.
The prosperity of modern states is dependent on the amount of iron rust
which they possess and utilize. England, United States, Germany, all
nations are competing to see which can dig the most iron rust out of the
ground and make out of it railroads, bridges, buildings, machinery,
battleships and such other tools and toys and then let them relapse into
rust again. Civilization can be measured by the amount of iron rusted
per capita, or better, by the amount rescued from rust.
But we are devoting so much space to the consideration of the material
aspects of iron that we are like to neglect its esthetic and ethical
uses. The beauty of nature is very largely dependent upon the fact that
iron rust and, in fact, all the common compounds of iron are colored.
Few elements can assume so many tints. Look at the paint pot cañons of
the Yellowstone. Cheap glass bottles turn out brown, green, blue, yellow
or black, according to the amount and kind of iron they contain. We
build a house of cream-colored brick, varied with speckled brick and
adorned with terra cotta ornaments of red, yellow and green, all due to
iron. Iron rusts, therefore it must be painted; but what is there better
to paint it with than iron rust itself? It is cheap and durable, for it
cannot rust any more than a dead man can die. And what is also of
importance, it is a good, strong, clean looking, endurable color.
Whenever we take a trip on the railroad and see the miles of cars, the
acres of roofing and wall, the towns full of brick buildings, we rejoice
that iron rust is red, not white or some leas satisfying color.
We do not know why it is so. Zinc and aluminum are metals very much like
iron in chemical properties, but all their salts are colorless. Why is
it that the most useful of the metals forms the most beautiful
compounds? Some say, Providence; some say, chance; some say nothing. But
if it had not been so we would have lost most of the beauty of rocks and
trees and human beings. For the leaves and the flowers would all be
white, and all the men and women would look like walking corpses.
Without color in the flower what would the bees and painters do? If all
the grass and trees were white, it would be like winter all the year
round. If we had white blood in our veins like some of the insects it
would be hard lines for our poets. And what would become of our morality
if we could not blush?
"As for me, I thrill to see
The bloom a velvet cheek discloses!
Made of dust! I well believe it,
So are lilies, so are roses."
An etiolated earth would be hardly worth living in.
The chlorophyll of the leaves and the hemoglobin of the blood are
similar in constitution. Chlorophyll contains magnesium in place of iron
but iron is necessary to its formation. We all know how pale a plant
gets if its soil is short of iron. It is the iron in the leaves that
enables the plants to store up the energy of the sunshine for their own
use and ours. It is the iron in our blood that enables us to get the
iron out of iron rust and make it into machines to supplement our feeble
hands. Iron is for us internally the carrier of energy, just as in the
form of a trolley wire or of a third rail it conveys power to the
electric car. Withdraw the iron from the blood as indicated by the
pallor of the cheeks, and we become weak, faint and finally die. If the
amount of iron in the blood gets too small the disease germs that are
always attacking us are no longer destroyed, but multiply without check
and conquer us. When the iron ceases to work efficiently we are killed
by the poison we ourselves generate.
Counting the number of iron-bearing corpuscles in the blood is now a
common method of determining disease. It might also be useful in moral
diagnosis. A microscopical and chemical laboratory attached to the
courtroom would give information of more value than some of the evidence
now obtained. For the anemic and the florid vices need very different
treatment. An excess or a deficiency of iron in the body is liable to
result in criminality. A chemical system of morals might be developed on
this basis. Among the ferruginous sins would be placed murder, violence
and licentiousness. Among the non-ferruginous, cowardice, sloth and
lying. The former would be mostly sins of commission, the latter, sins
of omission. The virtues could, of course, be similarly classified; the
ferruginous virtues would include courage, self-reliance and
hopefulness; the non-ferruginous, peaceableness, meekness and chastity.
According to this ethical criterion the moral man would be defined as
one whose conduct is better than we should expect from the per cent. of
iron in his blood.
The reason why iron is able to serve this unique purpose of conveying
life-giving air to all parts of the body is because it rusts so readily.
Oxidation and de-oxidation proceed so quietly that the tenderest cells
are fed without injury. The blood changes from red to blue and _vice
versa_ with greater ease and rapidity than in the corresponding
alternations of social status in a democracy. It is because iron is so
rustable that it is so useful. The factories with big scrap-heaps of
rusting machinery are making the most money. The pyramids are the most
enduring structures raised by the hand of man, but they have not
sheltered so many people in their forty centuries as our skyscrapers
that are already rusting.
We have to carry on this eternal conflict against rust because oxygen is
the most ubiquitous of the elements and iron can only escape its ardent
embraces by hiding away in the center of the earth. The united elements,
known to the chemist as iron oxide and to the outside world as rust, are
among the commonest of compounds and their colors, yellow and red like
the Spanish flag, are displayed on every mountainside. From the time of
Tubal Cain man has ceaselessly labored to divorce these elements and,
having once separated them, to keep them apart so that the iron may be
retained in his service. But here, as usual, man is fighting against
nature and his gains, as always, are only temporary. Sooner or later his
vigilance is circumvented and the metal that he has extricated by the
fiery furnace returns to its natural affinity. The flint arrowheads, the
bronze spearpoints, the gold ornaments, the wooden idols of prehistoric
man are still to be seen in our museums, but his earliest steel swords
have long since crumbled into dust.
Every year the blast furnaces of the world release 72,000,000 tons of
iron from its oxides and every year a large part, said to be a quarter
of that amount, reverts to its primeval forms. If so, then man after
five thousand years of metallurgical industry has barely got three years
ahead of nature, and should he cease his efforts for a generation there
would be little left to show that man had ever learned to extract iron
from its ores. The old question, "What becomes of all the pins?" may be
as well asked of rails, pipes and threshing machines. The end of all
iron is the same. However many may be its metamorphoses while in the
service of man it relapses at last into its original state of oxidation.
To save a pound of iron from corrosion is then as much a benefit to the
world as to produce another pound from the ore. In fact it is of much
greater benefit, for it takes four pounds of coal to produce one pound
of steel, so whenever a piece of iron is allowed to oxidize it means
that four times as much coal must be oxidized in order to replace it.
And the beds of coal will be exhausted before the beds of iron ore.
If we are ever to get ahead, if we are to gain any respite from this
enormous waste of labor and natural resources, we must find ways of
preventing the iron which we have obtained and fashioned into useful
tools from being lost through oxidation. Now there is only one way of
keeping iron and oxygen from uniting and that is to keep them apart. A
very thin dividing wall will serve for the purpose, for instance, a film
of oil. But ordinary oil will rub off, so it is better to cover the
surface with an oil-like linseed which oxidizes to a hard elastic and
adhesive coating. If with linseed oil we mix iron oxide or some other
pigment we have a paint that will protect iron perfectly so long as it
is unbroken. But let the paint wear off or crack so that air can get at
the iron, then rust will form and spread underneath the paint on all
sides. The same is true of the porcelain-like enamel with which our
kitchen iron ware is nowadays coated. So long as the enamel holds it is
all right but once it is broken through at any point it begins to scale
off and gets into our food.
Obviously it would be better for some purposes if we could coat our
iron with another and less easily oxidized metal than with such
dissimilar substances as paint or porcelain. Now the nearest relative to
iron is nickel, and a layer of this of any desired thickness may be
easily deposited by electricity upon any surface however irregular.
Nickel takes a bright polish and keeps it well, so nickel plating has
become the favorite method of protection for small objects where the
expense is not prohibitive. Copper plating is used for fine wires. A
sheet of iron dipped in melted tin comes out coated with a thin adhesive
layer of the latter metal. Such tinned plate commonly known as "tin" has
become the favorite material for pans and cans. But if the tin is
scratched the iron beneath rusts more rapidly than if the tin were not
there, for an electrolytic action is set up and the iron, being the
negative element of the couple, suffers at the expense of the tin.
With zinc it is quite the opposite. Zinc is negative toward iron, so
when the two are in contact and exposed to the weather the zinc is
oxidized first. A zinc plating affords the protection of a Swiss Guard,
it holds out as long as possible and when broken it perishes to the last
atom before it lets the oxygen get at the iron. The zinc may be applied
in four different ways. (1) It may be deposited by electrolysis as in
nickel plating, but the zinc coating is more apt to be porous. (2) The
sheets or articles may be dipped in a bath of melted zinc. This gives us
the familiar "galvanized iron," the most useful and when well done the
most effective of rust preventives. Besides these older methods of
applying zinc there are now two new ones. (3) One is the Schoop process
by which a wire of zinc or other metal is fed into an oxy-hydrogen air
blast of such heat and power that it is projected as a spray of minute
drops with the speed of bullets and any object subjected to the
bombardment of this metallic mist receives a coating as thick as
desired. The zinc spray is so fine and cool that it may be received on
cloth, lace, or the bare hand. The Schoop metallizing process has
recently been improved by the use of the electric current instead of the
blowpipe for melting the metal. Two zinc wires connected with any
electric system, preferably the direct, are fed into the "pistol." Where
the wires meet an electric arc is set up and the melted zinc is sprayed
out by a jet of compressed air. (4) In the Sherardizing process the
articles are put into a tight drum with zinc dust and heated to 800° F.
The zinc at this temperature attacks the iron and forms a series of
alloys ranging from pure zinc on the top to pure iron at the bottom of
the coating. Even if this cracks in part the iron is more or less
protected from corrosion so long as any zinc remains. Aluminum is used
similarly in the calorizing process for coating iron, copper or brass.
First a surface alloy is formed by heating the metal with aluminum
powder. Then the temperature is raised to a high degree so as to cause
the aluminum on the surface to diffuse into the metal and afterwards it
is again baked in contact with aluminum dust which puts upon it a
protective plating of the pure aluminum which does not oxidize.
[Illustration: PHOTOMICROGRAPHS SHOWING THE STRUCTURE OF STEEL MADE BY
PROFESSOR E.G. MARTIN OF PURDUE UNIVERSITY
1. Cold-worked steel showing ferrite and sorbite (enlarged 500 times)
2. Steel showing pearlite crystals (enlarged 500 times)
3. Structure characteristic of air-cooled steel (enlarged 50 times)
4. The triangular structure characteristic of cast steel showing ferrite
and pearlite (enlarged 50 times)]
[Illustration: Courtesy of E.G. Mahin
THE MICROSCOPIC STRUCTURE OF METALS
1. Malleabilized casting; temper carbon in ferrite (enlarged 50 times)
2. Type metal; lead-antimony alloy in matrix of lead (enlarged 100
times)
3. Gray cast iron; carbon as graphite (enlarged 500 times)
4. Steel composed of cementite (white) and pearlite (black) (enlarged 50
times)]
Another way of protecting iron ware from rusting is to rust it. This is
a sort of prophylactic method like that adopted by modern medicine where
inoculation with a mild culture prevents a serious attack of the
disease. The action of air and water on iron forms a series of compounds
and mixtures of them. Those that contain least oxygen are hard, black
and magnetic like iron itself. Those that have most oxygen are red and
yellow powders. By putting on a tight coating of the black oxide we can
prevent or hinder the oxidation from going on into the pulverulent
stage. This is done in several ways. In the Bower-Barff process the
articles to be treated are put into a closed retort and a current of
superheated steam passed through for twenty minutes followed by a
current of producer gas (carbon monoxide), to reduce any higher oxides
that may have been formed. In the Gesner process a current of gasoline
vapor is used as the reducing agent. The blueing of watch hands, buckles
and the like may be done by dipping them into an oxidizing bath such as
melted saltpeter. But in order to afford complete protection the layer
of black oxide must be thickened by repeating the process which adds to
the time and expense. This causes a slight enlargement and the high
temperature often warps the ware so it is not suitable for nicely
adjusted parts of machinery and of course tools would lose their temper
by the heat.
A new method of rust proofing which is free from these disadvantages is
the phosphate process invented by Thomas Watts Coslett, an English
chemist, in 1907, and developed in America by the Parker Company of
Detroit. This consists simply in dipping the sheet iron or articles into
a tank filled with a dilute solution of iron phosphate heated nearly to
the boiling point by steam pipes. Bubbles of hydrogen stream off rapidly
at first, then slower, and at the end of half an hour or longer the
action ceases, and the process is complete. What has happened is that
the iron has been converted into a basic iron phosphate to a depth
depending upon the density of articles processed. Any one who has
studied elementary qualitative analysis will remember that when he added
ammonia to his "unknown" solution, iron and phosphoric acid, if present,
were precipitated together, or in other words, iron phosphate is
insoluble except in acids. Therefore a superficial film of such
phosphate will protect the iron underneath except from acids. This film
is not a coating added on the outside like paint and enamel or tin and
nickel plate. It is therefore not apt to scale off and it does not
increase the size of the article. No high heat is required as in the
Sherardizing and Bower-Barff processes, so steel tools can be treated
without losing their temper or edge.
The deposit consisting of ferrous and ferric phosphates mixed with black
iron oxide may be varied in composition, texture and color. It is
ordinarily a dull gray and oiling gives a soft mat black more in
accordance with modern taste than the shiny nickel plating that
delighted our fathers. Even the military nowadays show more quiet taste
than formerly and have abandoned their glittering accoutrements.
The phosphate bath is not expensive and can be used continuously for
months by adding more of the concentrated solution to keep up the
strength and removing the sludge that is precipitated. Besides the iron
the solution contains the phosphates of other metals such as calcium or
strontium, manganese, molybdenum, or tungsten, according to the
particular purpose. Since the phosphating solution does not act on
nickel it may be used on articles that have been partly nickel-plated so
there may be produced, for instance, a bright raised design against a
dull black background. Then, too, the surface left by the Parker process
is finely etched so it affords a good attachment for paint or enamel if
further protection is needed. Even if the enamel does crack, the iron
beneath is not so apt to rust and scale off the coating.
These, then, are some of the methods which are now being used to combat
our eternal enemy, the rust that doth corrupt. All of them are useful in
their several ways. No one of them is best for all purposes. The claim
of "rust-proof" is no more to be taken seriously than "fire-proof." We
should rather, if we were finical, have to speak of "rust-resisting"
coatings as we do of "slow-burning" buildings. Nature is insidious and
unceasing in her efforts to bring to ruin the achievements of mankind
and we need all the weapons we can find to frustrate her destructive
determination.
But it is not enough for us to make iron superficially resistant to rust
from the atmosphere. We should like also to make it so that it would
withstand corrosion by acids, then it could be used in place of the
large and expensive platinum or porcelain evaporating pans and similar
utensils employed in chemical works. This requirement also has been met
in the non-corrosive forms of iron, which have come into use within the
last five years. One of these, "tantiron," invented by a British
metallurgist, Robert N. Lennox, in 1912, contains 15 per cent. of
silicon. Similar products are known as "duriron" and "Buflokast" in
America, "metilure" in France, "ileanite" in Italy and "neutraleisen" in
Germany. It is a silvery-white close-grained iron, very hard and rather
brittle, somewhat like cast iron but with silicon as the main additional
ingredient in place of carbon. It is difficult to cut or drill but may
be ground into shape by the new abrasives. It is rustproof and is not
attacked by sulfuric, nitric or acetic acid, hot or cold, diluted or
concentrated. It does not resist so well hydrochloric acid or sulfur
dioxide or alkalies.
The value of iron lies in its versatility. It is a dozen metals in one.
It can be made hard or soft, brittle or malleable, tough or weak,
resistant or flexible, elastic or pliant, magnetic or non-magnetic, more
or less conductive to electricity, by slight changes of composition or
mere differences of treatment. No wonder that the medieval mind ascribed
these mysterious transformations to witchcraft. But the modern
micrometallurgist, by etching the surface of steel and photographing it,
shows it up as composite as a block of granite. He is then able to pick
out its component minerals, ferrite, austenite, martensite, pearlite,
graphite, cementite, and to show how their abundance, shape and
arrangement contribute to the strength or weakness of the specimen. The
last of these constituents, cementite, is a definite chemical compound,
an iron carbide, Fe_{3}C, containing 6.6 per cent. of carbon, so hard as
to scratch glass, very brittle, and imparting these properties to
hardened steel and cast iron.
With this knowledge at his disposal the iron-maker can work with his
eyes open and so regulate his melt as to cause these various
constituents to crystallize out as he wants them to. Besides, he is no
longer confined to the alloys of iron and carbon. He has ransacked the
chemical dictionary to find new elements to add to his alloys, and some
of these rarities have proved to possess great practical value.
Vanadium, for instance, used to be put into a fine print paragraph in
the back of the chemistry book, where the class did not get to it until
the term closed. Yet if it had not been for vanadium steel we should
have no Ford cars. Tungsten, too, was relegated to the rear, and if the
student remembered it at all it was because it bothered him to
understand why its symbol should be W instead of T. But the student of
today studies his lesson in the light of a tungsten wire and relieves
his mind by listening to a phonograph record played with a "tungs-tone"
stylus. When I was assistant in chemistry an "analysis" of steel
consisted merely in the determination of its percentage of carbon, and I
used to take Saturday for it so I could have time enough to complete the
combustion. Now the chemists of a steel works' laboratory may have to
determine also the tungsten, chromium, vanadium, titanium, nickel,
cobalt, phosphorus, molybdenum, manganese, silicon and sulfur, any or
all of them, and be spry about it, because if they do not get the report
out within fifteen minutes while the steel is melting in the electrical
furnace the whole batch of 75 tons may go wrong. I'm glad I quit the
laboratory before they got to speeding up chemists so.
The quality of the steel depends upon the presence and the relative
proportions of these ingredients, and a variation of a tenth of 1 per
cent. in certain of them will make a different metal out of it. For
instance, the steel becomes stronger and tougher as the proportion of
nicked is increased up to about 15 per cent. Raising the percentage to
25 we get an alloy that does not rust or corrode and is non-magnetic,
although both its component metals, iron and nickel, are by themselves
attracted by the magnet. With 36 per cent. nickel and 5 per cent.
manganese we get the alloy known as "invar," because it expands and
contracts very little with changes of temperature. A bar of the best
form of invar will expand less than one-millionth part of its length for
a rise of one degree Centigrade at ordinary atmospheric temperature. For
this reason it is used in watches and measuring instruments. The alloy
of iron with 46 per cent. nickel is called "platinite" because its rate
of expansion and contraction is the same as platinum and glass, and so
it can be used to replace the platinum wire passing through the glass of
an electric light bulb.
A manganese steel of 11 to 14 per cent. is too hard to be machined. It
has to be cast or ground into shape and is used for burglar-proof safes
and armor plate. Chrome steel is also hard and tough and finds use in
files, ball bearings and projectiles. Titanium, which the iron-maker
used to regard as his implacable enemy, has been drafted into service as
a deoxidizer, increasing the strength and elasticity of the steel. It is
reported from France that the addition of three-tenths of 1 per cent. of
zirconium to nickel steel has made it more resistant to the German
perforating bullets than any steel hitherto known. The new "stainless"
cutlery contains 12 to 14 per cent. of chromium.
With the introduction of harder steels came the need of tougher tools to
work them. Now the virtue of a good tool steel is the same as of a good
man. It must be able to get hot without losing its temper. Steel of the
old-fashioned sort, as everybody knows, gets its temper by being heated
to redness and suddenly cooled by quenching or plunging it into water or
oil. But when the point gets heated up again, as it does by friction in
a lathe, it softens and loses its cutting edge. So the necessity of
keeping the tool cool limited the speed of the machine.
But about 1868 a Sheffield metallurgist, Robert F. Mushet, found that a
piece of steel he was working with did not require quenching to harden
it. He had it analyzed to discover the meaning of this peculiarity and
learned that it contained tungsten, a rare metal unrecognized in the
metallurgy of that day. Further investigation showed that steel to which
tungsten and manganese or chromium had been added was tougher and
retained its temper at high temperature better than ordinary carbon
steel. Tools made from it could be worked up to a white heat without
losing their cutting power. The new tools of this type invented by
"Efficiency" Taylor at the Bethlehem Steel Works in the nineties have
revolutionized shop practice the world over. A tool of the old sort
could not cut at a rate faster than thirty feet a minute without
overheating, but the new tungsten tools will plow through steel ten
times as fast and can cut away a ton of the material in an hour. By
means of these high-speed tools the United States was able to turn out
five times the munitions that it could otherwise have done in the same
time. On the other hand, if Germany alone had possessed the secret of
the modern steels no power could have withstood her. A slight
superiority in metallurgy has been the deciding factor in many a battle.
Those of my readers who have had the advantages of Sunday school
training will recall the case described in I Samuel 13:19-22.
By means of these new metals armor plate has been made
invulnerable--except to projectiles pointed with similar material.
Flying has been made possible through engines weighing no more than two
pounds per horse power. The cylinders of combustion engines and the
casing of cannon have been made to withstand the unprecedented pressure
and corrosive action of the fiery gases evolved within. Castings are
made so hard that they cannot be cut--save with tools of the same sort.
In the high-speed tools now used 20 or 30 per cent, of the iron is
displaced by other ingredients; for example, tungsten from 14 to 25 per
cent., chromium from 2 to 7 per cent., vanadium from 1/2 to 1-1/2 per
cent., carbon from 6 to 8 per cent., with perhaps cobalt up to 4 per
cent. Molybdenum or uranium may replace part of the tungsten.
Some of the newer alloys for high-speed tools contain no iron at all.
That which bears the poetic name of star-stone, stellite, is composed of
chromium, cobalt and tungsten in varying proportions. Stellite keeps a
hard cutting edge and gets tougher as it gets hotter. It is very hard
and as good for jewelry as platinum except that it is not so expensive.
Cooperite, its rival, is an alloy of nickel and zirconium, stronger,
lighter and cheaper than stellite.
Before the war nearly half of the world's supply of tungsten ore
(wolframite) came from Burma. But although Burma had belonged to the
British for a hundred years they had not developed its mineral resources
and the tungsten trade was monopolized by the Germans. All the ore was
shipped to Germany and the British Admiralty was content to buy from the
Germans what tungsten was needed for armor plate and heavy guns. When
the war broke out the British had the ore supply, but were unable at
first to work it because they were not familiar with the processes.
Germany, being short of tungsten, had to sneak over a little from
Baltimore in the submarine _Deutschland_. In the United States before
the war tungsten ore was selling at $6.50 a unit, but by the beginning
of 1916 it had jumped to $85 a unit. A unit is 1 per cent. of tungsten
trioxide to the ton, that is, twenty pounds. Boulder County, Colorado,
and San Bernardino, California, then had mining booms, reminding one of
older times. Between May and December, 1918, there was manufactured in
the United States more than 45,500,000 pounds of tungsten steel
containing some 8,000,000 pounds of tungsten.
If tungsten ores were more abundant and the metal more easily
manipulated, it would displace steel for many purposes. It is harder
than steel or even quartz. It never rusts and is insoluble in acids. Its
expansion by heat is one-third that of iron. It is more than twice as
heavy as iron and its melting point is twice as high. Its electrical
resistance is half that of iron and its tensile strength is a third
greater than the strongest steel. It can be worked into wire .0002 of an
inch in diameter, almost too thin to be seen, but as strong as copper
wire ten times the size.
The tungsten wires in the electric lamps are about .03 of an inch in
diameter, and they give three times the light for the same consumption
of electricity as the old carbon filament. The American manufacturers of
the tungsten bulb have very appropriately named their lamp "Mazda" after
the light god of the Zoroastrians. To get the tungsten into wire form
was a problem that long baffled the inventors of the world, for it was
too refractory to be melted in mass and too brittle to be drawn. Dr.
W.D. Coolidge succeeded in accomplishing the feat in 1912 by reducing
the tungstic acid by hydrogen and molding the metallic powder into a bar
by pressure. This is raised to a white heat in the electric furnace,
taken out and rolled down, and the process repeated some fifty times,
until the wire is small enough so it can be drawn at a red heat through
diamond dies of successively smaller apertures.
The German method of making the lamp filaments is to squirt a mixture of
tungsten powder and thorium oxide through a perforated diamond of the
desired diameter. The filament so produced is drawn through a chamber
heated to 2500° C. at a velocity of eight feet an hour, which
crystallizes the tungsten into a continuous thread.
The first metallic filament used in the electric light on a commercial
scale was made of tantalum, the metal of Tantalus. In the period
1905-1911 over 100,000,000 tantalus lamps were sold, but tungsten
displaced them as soon as that metal could be drawn into wire.
A recent rival of tungsten both as a filament for lamps and hardener for
steel is molybdenum. One pound of this metal will impart more resiliency
to steel than three or four pounds of tungsten. The molybdenum steel,
because it does not easily crack, is said to be serviceable for
armor-piercing shells, gun linings, air-plane struts, automobile axles
and propeller shafts. In combination with its rival as a
tungsten-molybdenum alloy it is capable of taking the place of the
intolerably expensive platinum, for it resists corrosion when used for
spark plugs and tooth plugs. European steel men have taken to molybdenum
more than Americans. The salts of this metal can be used in dyeing and
photography.
Calcium, magnesium and aluminum, common enough in their compounds, have
only come into use as metals since the invention of the electric
furnace. Now the photographer uses magnesium powder for his flashlight
when he wants to take a picture of his friends inside the house, and the
aviator uses it when he wants to take a picture of his enemies on the
open field. The flares prepared by our Government for the war consist of
a sheet iron cylinder, four feet long and six inches thick, containing a
stick of magnesium attached to a tightly rolled silk parachute twenty
feet in diameter when expanded. The whole weighed 32 pounds. On being
dropped from the plane by pressing a button, the rush of air set
spinning a pinwheel at the bottom which ignited the magnesium stick and
detonated a charge of black powder sufficient to throw off the case and
release the parachute. The burning flare gave off a light of 320,000
candle power lasting for ten minutes as the parachute slowly descended.
This illuminated the ground on the darkest night sufficiently for the
airman to aim his bombs or to take photographs.
The addition of 5 or 10 per cent. of magnesium to aluminum gives an
alloy (magnalium) that is almost as light as aluminum and almost as
strong as steel. An alloy of 90 per cent. aluminum and 10 per cent.
calcium is lighter and harder than aluminum and more resistant to
corrosion. The latest German airplane, the "Junker," was made entirely
of duralumin. Even the wings were formed of corrugated sheets of this
alloy instead of the usual doped cotton-cloth. Duralumin is composed of
about 85 per cent. of aluminum, 5 per cent. of copper, 5 per cent. of
zinc and 2 per cent. of tin.
When platinum was first discovered it was so cheap that ingots of it
were gilded and sold as gold bricks to unwary purchasers. The Russian
Government used it as we use nickel, for making small coins. But this is
an exception to the rule that the demand creates the supply. Platinum is
really a "rare metal," not merely an unfamiliar one. Nowhere except in
the Urals is it found in quantity, and since it seems indispensable in
chemical and electrical appliances, the price has continually gone up.
Russia collapsed into chaos just when the war work made the heaviest
demand for platinum, so the governments had to put a stop to its use for
jewelry and photography. The "gold brick" scheme would now have to be
reversed, for gold is used as a cheaper metal to "adulterate" platinum.
All the members of the platinum family, formerly ignored, were pressed
into service, palladium, rhodium, osmium, iridium, and these, alloyed
with gold or silver, were employed more or less satisfactorily by the
dentist, chemist and electrician as substitutes for the platinum of
which they had been deprived. One of these alloys, composed of 20 per
cent. palladium and 80 per cent. gold, and bearing the telescoped name
of "palau" (palladium au-rum) makes very acceptable crucibles for the
laboratory and only costs half as much as platinum. "Rhotanium" is a
similar alloy recently introduced. The points of our gold pens are
tipped with an osmium-iridium alloy. It is a pity that this family of
noble metals is so restricted, for they are unsurpassed in tenacity and
incorruptibility. They could be of great service to the world in war and
peace. As the "Bad Child" says in his "Book of Beasts":
I shoot the hippopotamus with bullets made of platinum,
Because if I use leaden ones, his hide is sure to flatten 'em.
Along in the latter half of the last century chemists had begun to
perceive certain regularities and relationships among the various
elements, so they conceived the idea that some sort of a pigeon-hole
scheme might be devised in which the elements could be filed away in the
order of their atomic weights so that one could see just how a certain
element, known or unknown, would behave from merely observing its
position in the series. Mendeléef, a Russian chemist, devised the most
ingenious of such systems called the "periodic law" and gave proof that
there was something in his theory by predicting the properties of three
metallic elements, then unknown but for which his arrangement showed
three empty pigeon-holes. Sixteen years later all three of these
predicted elements had been discovered, one by a Frenchman, one by a
German and one by a Scandinavian, and named from patriotic impulse,
gallium, germanium and scandium. This was a triumph of scientific
prescience as striking as the mathematical proof of the existence of the
planet Neptune by Leverrier before it had been found by the telescope.
But although Mendeléef's law told "the truth," it gradually became
evident that it did not tell "the whole truth and nothing but the
truth," as the lawyers put it. As usually happens in the history of
science the hypothesis was found not to explain things so simply and
completely as was at first assumed. The anomalies in the arrangement did
not disappear on closer study, but stuck out more conspicuously. Though
Mendeléef had pointed out three missing links, he had failed to make
provision for a whole group of elements since discovered, the inert
gases of the helium-argon group. As we now know, the scheme was built
upon the false assumptions that the elements are immutable and that
their atomic weights are invariable.
The elements that the chemists had most difficulty in sorting out and
identifying were the heavy metals found in the "rare earths." There were
about twenty of them so mixed up together and so much alike as to baffle
all ordinary means of separating them. For a hundred years chemists
worked over them and quarreled over them before they discovered that
they had a commercial value. It was a problem as remote from
practicality as any that could be conceived. The man in the street did
not see why chemists should care whether there were two didymiums any
more than why theologians should care whether there were two Isaiahs.
But all of a sudden, in 1885, the chemical puzzle became a business
proposition. The rare earths became household utensils and it made a big
difference with our monthly gas bills whether the ceria and the thoria
in the burner mantles were absolutely pure or contained traces of some
of the other elements that were so difficult to separate.
This sudden change of venue from pure to applied science came about
through a Viennese chemist, Dr. Carl Auer, later and in consequence
known as Baron Auer von Welsbach. He was trying to sort out the rare
earths by means of the spectroscopic method, which consists ordinarily
in dipping a platinum wire into a solution of the unknown substance and
holding it in a colorless gas flame. As it burns off, each element gives
a characteristic color to the flame, which is seen as a series of lines
when looked at through the spectroscope. But the flash of the flame from
the platinum wire was too brief to be studied, so Dr. Auer hit upon the
plan of soaking a thread in the liquid and putting this in the gas jet.
The cotton of course burned off at once, but the earths held together
and when heated gave off a brilliant white light, very much like the
calcium or limelight which is produced by heating a stick of quicklime
in the oxy-hydrogen flame. But these rare earths do not require any such
intense heat as that, for they will glow in an ordinary gas jet.
So the Welsbach mantle burner came into use everywhere and rescued the
coal gas business from the destruction threatened by the electric light.
It was no longer necessary to enrich the gas with oil to make its flame
luminous, for a cheaper fuel gas such as is used for a gas stove will
give, with a mantle, a fine white light of much higher candle power than
the ordinary gas jet. The mantles are knit in narrow cylinders on
machines, cut off at suitable lengths, soaked in a solution of the salts
of the rare earths and dried. Artificial silk (viscose) has been found
better than cotton thread for the mantles, for it is solid, not hollow,
more uniform in quality and continuous instead of being broken up into
one-inch fibers. There is a great deal of difference in the quality of
these mantles, as every one who has used them knows. Some that give a
bright glow at first with the gas-cock only half open will soon break up
or grow dull and require more gas to get any kind of a light out of
them. Others will last long and grow better to the last. Slight
impurities in the earths or the gas will speedily spoil the light. The
best results are obtained from a mixture of 99 parts thoria and 1 part
ceria. It is the ceria that gives the light, yet a little more of it
will lower the luminosity.
The non-chemical reader is apt to be confused by the strange names and
their varied terminations, but he need not be when he learns that the
new metals are given names ending in _-um_, such as sodium, cerium,
thorium, and that their oxides (compounds with oxygen, the earths) are
given the termination _-a_, like soda, ceria, thoria. So when he sees a
name ending in _-um_ let him picture to himself a metal, any metal since
they mostly look alike, lead or silver, for example. And when he comes
across a name ending in _-a_ he may imagine a white powder like lime.
Thorium, for instance, is, as its name implies, a metal named after the
thunder god Thor, to whom we dedicate one day in each week, Thursday.
Cerium gets its name from the Roman goddess of agriculture by way of the
asteroid.
The chief sources of the material for the Welsbach burners is monazite,
a glittering yellow sand composed of phosphate of cerium with some 5 per
cent. of thorium. In 1916 the United States imported 2,500,000 pounds of
monazite from Brazil and India, most of which used to go to Germany. In
1895 we got over a million and a half pounds from the Carolinas, but the
foreign sand is richer and cheaper. The price of the salts of the rare
metals fluctuates wildly. In 1895 thorium nitrate sold at $200 a pound;
in 1913 it fell to $2.60, and in 1916 it rose to $8.
Since the monazite contains more cerium than thorium and the mantles
made from it contain more thorium than cerium, there is a superfluity of
cerium. The manufacturers give away a pound of cerium salts with every
purchase of a hundred pounds of thorium salts. It annoyed Welsbach to
see the cerium residues thrown away and accumulating around his mantle
factory, so he set out to find some use for it. He reduced the mixed
earths to a metallic form and found that it gave off a shower of sparks
when scratched. An alloy of cerium with 30 or 35 per cent. of iron
proved the best and was put on the market in the form of automatic
lighters. A big business was soon built up in Austria on the basis of
this obscure chemical element rescued from the dump-heap. The sale of
the cerite lighters in France threatened to upset the finances of the
republic, which derived large revenue from its monopoly of match-making,
so the French Government imposed a tax upon every man who carried one.
American tourists who bought these lighters in Germany used to be much
annoyed at being held up on the French frontier and compelled to take
out a license. During the war the cerium sparklers were much used in the
trenches for lighting cigarettes, but--as those who have seen "The
Better 'Ole" will know--they sometimes fail to strike fire. Auer-metal
or cerium-iron alloy was used in munitions to ignite hand grenades and
to blazon the flight of trailer shells. There are many other pyrophoric
(light-producing) alloys, including steel, which our ancestors used with
flint before matches and percussion caps were invented.
There are more than fifty metals known and not half of them have come
into common use, so there is still plenty of room for the expansion of
the science of metallurgy. If the reader has not forgotten his
arithmetic of permutations he can calculate how many different alloys
may be formed by varying the combinations and proportions of these
fifty. We have seen how quickly elements formerly known only to
chemists--and to some of them known only by name--have become
indispensable in our daily life. Any one of those still unutilized may
be found to have peculiar properties that fit it for filling a long
unfelt want in modern civilization.
Who, for instance, will find a use for gallium, the metal of France? It
was described in 1869 by Mendeléef in advance of its advent and has been
known in person since 1875, but has not yet been set to work. It is
such a remarkable metal that it must be good for something. If you saw
it in a museum case on a cold day you might take it to be a piece of
aluminum, but if the curator let you hold it in your hand--which he
won't--it would melt and run over the floor like mercury. The melting
point is 87° Fahr. It might be used in thermometers for measuring
temperatures above the boiling point of mercury were it not for the
peculiar fact that gallium wets glass so it sticks to the side of the
tube instead of forming a clear convex curve on top like mercury.
Then there is columbium, the American metal. It is strange that an
element named after Columbia should prove so impractical. Columbium is a
metal closely resembling tantalum and tantalum found a use as electric
light filaments. A columbium lamp should appeal to our patriotism.
The so-called "rare elements" are really abundant enough considering the
earth's crust as a whole, though they are so thinly scattered that they
are usually overlooked and hard to extract. But whenever one of them is
found valuable it is soon found available. A systematic search generally
reveals it somewhere in sufficient quantity to be worked. Who, then,
will be the first to discover a use for indium, germanium, terbium,
thulium, lanthanum, neodymium, scandium, samarium and others as unknown
to us as tungsten was to our fathers?
As evidence of the statement that it does not matter how rare an element
may be it will come into common use if it is found to be commonly
useful, we may refer to radium. A good rich specimen of radium ore,
pitchblende, may contain as much, as one part in 4,000,000. Madame
Curie, the brilliant Polish Parisian, had to work for years before she
could prove to the world that such an element existed and for years
afterwards before she could get the metal out. Yet now we can all afford
a bit of radium to light up our watch dials in the dark. The amount
needed for this is infinitesimal. If it were more it would scorch our
skins, for radium is an element in eruption. The atom throws off
corpuscles at intervals as a Roman candle throws off blazing balls. Some
of these particles, the alpha rays, are atoms of another element,
helium, charged with positive electricity and are ejected with a
velocity of 18,000 miles a second. Some of them, the beta rays, are
negative electrons, only about one seven-thousandth the size of the
others, but are ejected with almost the speed of light, 186,000 miles a
second. If one of the alpha projectiles strikes a slice of zinc sulfide
it makes a splash of light big enough to be seen with a microscope, so
we can now follow the flight of a single atom. The luminous watch dials
consist of a coating of zinc sulfide under continual bombardment by the
radium projectiles. Sir William Crookes invented this radium light
apparatus and called it a "spinthariscope," which is Greek for
"spark-seer."
Evidently if radium is so wasteful of its substance it cannot last
forever nor could it have forever existed. The elements then ate not
necessarily eternal and immutable, as used to be supposed. They have a
natural length of life; they are born and die and propagate, at least
some of them do. Radium, for instance, is the offspring of ionium,
which is the great-great-grandson of uranium, the heaviest of known
elements. Putting this chemical genealogy into biblical language we
might say: Uranium lived 5,000,000,000 years and begot Uranium X1, which
lived 24.6 days and begot Uranium X2, which lived 69 seconds and begot
Uranium 2, which lived 2,000,000 years and begot Ionium, which lived
200,000 years and begot Radium, which lived 1850 years and begot Niton,
which lived 3.85 days and begot Radium A, which lived 3 minutes and
begot Radium B, which lived 26.8 minutes and begot Radium C, which lived
19.5 minutes and begot Radium D, which lived 12 years and begot Radium
E, which lived 5 days and begot Polonium, which lived 136 days and begot
Lead.
The figures I have given are the times when half the parent substance
has gone over into the next generation. It will be seen that the chemist
is even more liberal in his allowance of longevity than was Moses with
the patriarchs. It appears from the above that half of the radium in any
given specimen will be transformed in about 2000 years. Half of what is
left will disappear in the next 2000 years, half of that in the next
2000 and so on. The reader can figure out for himself when it will all
be gone. He will then have the answer to the old Eleatic conundrum of
when Achilles will overtake the tortoise. But we may say that after
100,000 years there would not be left any radium worth mentioning, or in
other words practically all the radium now in existence is younger than
the human race. The lead that is found in uranium and has presumably
descended from uranium, behaves like other lead but is lighter. Its
atomic weight is only 206, while ordinary lead weighs 207. It appears
then that the same chemical element may have different atomic weights
according to its ancestry, while on the other hand different chemical
elements may have the same atomic weight. This would have seemed
shocking heresy to the chemists of the last century, who prided
themselves on the immutability of the elements and did not take into
consideration their past life or heredity. The study of these
radioactive elements has led to a new atomic theory. I suppose most of
us in our youth used to imagine the atom as a little round hard ball,
but now it is conceived as a sort of solar system with an
electropositive nucleus acting as the sun and negative electrons
revolving around it like the planets. The number of free positive
electrons in the nucleus varies from one in hydrogen to 92 in uranium.
This leaves room for 92 possible elements and of these all but six are
more or less certainly known and definitely placed in the scheme. The
atom of uranium, weighing 238 times the atom of hydrogen, is the
heaviest known and therefore the ultimate limit of the elements, though
it is possible that elements may be found beyond it just as the planet
Neptune was discovered outside the orbit of Uranus. Considering the
position of uranium and its numerous progeny as mentioned above, it is
quite appropriate that this element should bear the name of the father
of all the gods.
In these radioactive elements we have come upon sources of energy such
as was never dreamed of in our philosophy. The most striking peculiarity
of radium is that it is always a little warmer than its surroundings, no
matter how warm these may be. Slowly, spontaneously and continuously,
it decomposes and we know no way of hastening or of checking it. Whether
it is cooled in liquefied air or heated to its melting point the change
goes on just the same. An ounce of radium salt will give out enough heat
in one hour to melt an ounce of ice and in the next hour will raise this
water to the boiling point, and so on again and again without cessation
for years, a fire without fuel, a realization of the philosopher's lamp
that the alchemists sought in vain. The total energy so emitted is
millions of times greater than that produced by any chemical combination
such as the union of oxygen and hydrogen to form water. From the heavy
white salt there is continually rising a faint fire-mist like the
will-o'-the-wisp over a swamp. This gas is known as the emanation or
niton, "the shining one." A pound of niton would give off energy at the
rate of 23,000 horsepower; fine stuff to run a steamer, one would think,
but we must remember that it does not last. By the sixth day the power
would have fallen off by half. Besides, no one would dare to serve as
engineer, for the radiation will rot away the flesh of a living man who
comes near it, causing gnawing ulcers or curing them. It will not only
break down the complex and delicate molecules of organic matter but will
attack the atom itself, changing, it is believed, one element into
another, again the fulfilment of a dream of the alchemists. And its
rays, unseen and unfelt by us, are yet strong enough to penetrate an
armorplate and photograph what is behind it.
But radium is not the most mysterious of the elements but the least so.
It is giving out the secret that the other elements have kept. It
suggests to us that all the other elements in proportion to their weight
have concealed within them similar stores of energy. Astronomers have
long dazzled our imaginations by calculating the horsepower of the
world, making us feel cheap in talking about our steam engines and
dynamos when a minutest fraction of the waste dynamic energy of the
solar system would make us all as rich as millionaires. But the heavenly
bodies are too big for us to utilize in this practical fashion.
And now the chemists have become as exasperating as the astronomers, for
they give us a glimpse of incalculable wealth in the meanest substance.
For wealth is measured by the available energy of the world, and if a
few ounces of anything would drive an engine or manufacture nitrogenous
fertilizer from the air all our troubles would be over. Kipling in his
sketch, "With the Night Mail," and Wells in his novel, "The World Set
Free," stretched their imaginations in trying to tell us what it would
mean to have command of this power, but they are a little hazy in their
descriptions of the machinery by which it is utilized. The atom is as
much beyond our reach as the moon. We cannot rob its vault of the
treasure.
READING REFERENCES
The foregoing pages will not have achieved their aim unless their
readers have become sufficiently interested in the developments of
industrial chemistry to desire to pursue the subject further in some of
its branches. Assuming such interest has been aroused, I am giving below
a few references to books and articles which may serve to set the reader
upon the right track for additional information. To follow the rapid
progress of applied science it is necessary to read continuously such
periodicals as the _Journal of Industrial and Engineering Chemistry_
(New York), _Metallurgical and Chemical Engineering_ (New York),
_Journal of the Society of Chemical Industry_ (London), _Chemical
Abstracts_ (published by the American Chemical Society, Easton, Pa.),
and the various journals devoted to special trades. The reader may need
to be reminded that the United States Government publishes for free
distribution or at low price annual volumes or special reports dealing
with science and industry. Among these may be mentioned "Yearbook of the
Department of Agriculture"; "Mineral Resources of the United States,"
published by the United States Geological Survey in two annual volumes,
Vol. I on the metals and Vol. II on the non-metals; the "Annual Report
of the Smithsonian Institution," containing selected articles on pure
and applied science; the daily "Commerce Reports" and special bulletins
of Department of Commerce. Write for lists of publications of these
departments.
The following books on industrial chemistry in general are recommended
for reading and reference: "The Chemistry of Commerce" and "Some
Chemical Problems of To-Day" by Robert Kennedy Duncan (Harpers, N.Y.),
"Modern Chemistry and Its Wonders" by Martin (Van Nostrand), "Chemical
Discovery and Invention in the Twentieth Century" by Sir William A.
Tilden (Dutton, N.Y.), "Discoveries and Inventions of the Twentieth
Century" by Edward Cressy (Dutton), "Industrial Chemistry" by Allen
Rogers (Van Nostrand).
"Everyman's Chemistry" by Ellwood Hendrick (Harpers, Modern Science
Series) is written in a lively style and assumes no previous knowledge
of chemistry from the reader. The chapters on cellulose, gums, sugars
and oils are particularly interesting. "Chemistry of Familiar Things" by
S.S. Sadtler (Lippincott) is both comprehensive and comprehensible.
The following are intended for young readers but are not to be despised
by their elders who may wish to start in on an easy up-grade: "Chemistry
of Common Things" (Allyn & Bacon, Boston) is a popular high school
text-book but differing from most text-books in being readable and
attractive. Its descriptions of industrial processes are brief but
clear. The "Achievements of Chemical Science" by James C. Philip
(Macmillan) is a handy little book, easy reading for pupils.
"Introduction to the Study of Science" by W.P. Smith and E.G. Jewett
(Macmillan) touches upon chemical topics in a simple way.
On the history of commerce and the effect of inventions on society the
following titles may be suggested: "Outlines of Industrial History" by
E. Cressy (Macmillan); "The Origin of Invention," a study of primitive
industry, by O.T. Mason (Scribner); "The Romance of Commerce" by Gordon
Selbridge (Lane); "Industrial and Commercial Geography" or "Commerce and
Industry" by J. Russell Smith (Holt); "Handbook of Commercial Geography"
by G.G. Chisholm (Longmans).
The newer theories of chemistry and the constitution of the atom are
explained in "The Realities of Modern Science" by John Mills
(Macmillan), and "The Electron" by R.A. Millikan (University of Chicago
Press), but both require a knowledge of mathematics. The little book on
"Matter and Energy" by Frederick Soddy (Holt) is better adapted to the
general reader. The most recent text-book is the "Introduction to
General Chemistry" by H.N. McCoy and E.M. Terry. (Chicago, 1919.)
CHAPTER II
The reader who may be interested in following up this subject will find
references to all the literature in the summary by Helen R. Hosmer, of
the Research Laboratory of the General Electric Company, in the _Journal
of Industrial and Engineering Chemistry_, New York, for April, 1917.
Bucher's paper may be found in the same journal for March, and the issue
for September contains a full report of the action of U.S. Government
and a comparison of the various processes. Send fifteen cents to the
U.S. Department of Commerce (or to the nearest custom house) for
Bulletin No. 52, Special Agents Series on "Utilization of Atmospheric
Nitrogen" by T.H. Norton. The Smithsonian Institution of Washington has
issued a pamphlet on "Sources of Nitrogen Compounds in the United
States." In the 1913 report of the Smithsonian Institution there are two
fine articles on this subject: "The Manufacture of Nitrates from the
Atmosphere" and "The Distribution of Mankind," which discusses Sir
William Crookes' prediction of the exhaustion of wheat land. The D. Van
Nostrand Co., New York, publishes a monograph on "Fixation of
Atmospheric Nitrogen" by J. Knox, also "TNT and Other Nitrotoluenes" by
G.C. Smith. The American Cyanamid Company, New York, gives out some
attractive literature on their process.
"American Munitions 1917-1918," the report of Benedict Crowell, Director
of Munitions, to the Secretary of War, gives a fully illustrated
account of the manufacture of arms, explosives and toxic gases. Our war
experience in the "Oxidation of Ammonia" is told by C.L. Parsons in
_Journal of Industrial and Engineering Chemistry_, June, 1919, and
various other articles on the government munition work appeared in the
same journal in the first half of 1919. "The Muscle Shoals Nitrate
Plant" in _Chemical and Metallurgical Engineering_, January, 1919.
CHAPTER III
The Department of Agriculture or your congressman will send you
literature on the production and use of fertilizers. From your state
agricultural experiment station you can procure information as to local
needs and products. Consult the articles on potash salts and phosphate
rock in the latest volume of "Mineral Resources of the United States,"
Part II Non-Metals (published free by the U.S. Geological Survey). Also
consult the latest Yearbook of the Department of Agriculture. For
self-instruction, problems and experiments get "Extension Course in
Soils," Bulletin No. 355, U.S. Dept. of Agric. A list of all government
publications on "Soil and Fertilizers" is sent free by Superintendent of
Documents, Washington. The _Journal of Industrial and Engineering
Chemistry_ for July, 1917, publishes an article by W.C. Ebaugh on
"Potash and a World Emergency," and various articles on American sources
of potash appeared in the same _Journal_ October, 1918, and February,
1918. Bulletin 102, Part 2, of the United States National Museum
contains an interpretation of the fertilizer situation in 1917 by J.E.
Poque. On new potash deposits in Alsace and elsewhere see _Scientific
American Supplement_, September 14, 1918.