The ancient Greeks, when they looked about them on the world in which
they lived, came to the definite conclusion that everything is in
a constant state of flux, or change. Things animate and inanimate
gradually disintegrated and tended either to disappear (apparently) or
to change into other forms of matter. With their true æsthetic sense,
they felt it necessary that there should be some _one_ permanent thing
in the world, underlying all the changes which they saw going on about
them, and many of their early speculations were devoted to the nature
and constitution of this one “permanent thing.” Thales, of Myletus,
who flourished about 585 B. C., and who was, perhaps, the first great
philosopher and physicist, contended that the essential principle of
things,--the substance, or stuff, of all things,--must be _water_. He
held the view that, by condensation and rarefaction of water all things
rise, and he actually attempted an evolutionary account of the Genesis
of Man, Plants and Animals, with this idea as a basis for his thought.
Anaximenes said that _air_, or _ether_, must be the substance of
things. Heraclitus regarded _fire_ as the most primary element in
the universe,--from which all else arises. Anaximander said that the
“unlimited”--a sort of boundless, animated mass--is the ultimate
substance. Plato, as we know, contended that the permanent reality of
things was not anything material at all, but was mind, or _spirit_.
Empedocles, (495–435 B. C.) advanced the theory that there are four
elements--Earth, Air, Fire and Water. Anaxagoras contended that nothing
changed of itself, but that it is caused or made to change, and that
_that_ which produces these changes is the permanent reality. This he
believed to be a sort of mind or universal intelligence (_Nous_), but
he regarded this mind as strictly impersonal, as well as immaterial,
and did not attempt to answer the difficulty as to how mind can affect
matter in any detailed manner.
It was only natural that, prior to the discovery of the laws of the
indestructibility of matter and energy, that this sense of “change”
should have struck these early thinkers very forcibly, since they had
no means of ascertaining that, when matter disappears from our sight,
it is not actually destroyed. We now know that, when we burn a candle,
the candle disappears, but that the elements composing the candle are
merely changed into invisible gaseous compounds, which are no longer
visible to the human eye. Lacking delicate instruments of precision,
the ancients could not know this; to them, the matter of the candle
would have disappeared. Hence, it was only natural that they should
seek the ultimate reality behind these changes, and speculate as to its
origin and nature.
ALCHEMY
The modern science of chemistry is relatively new. It gradually
emerged from alchemy, which practically constituted the chemistry
of the middle ages. The objects of alchemy were various: (1) the
transmutation of the base metals into gold, by means of the so-called
“Philosopher’s Stone”; (2) The fixation of Mercury; (3) The discovery
of the elixir of Life, etc. These were the purely chemical aspects of
alchemy, but we now know that the alchemists had much more than this
in mind, in their experimental work, and that they hinted at their
true meaning in many of their veiled writings. Many of the higher
types of alchemists were also mystics, and when they wrote in chemical
symbols, they really concealed their inner meaning; they referred,
very largely, to the inner spirit of man, and the methods by which
this could be changed or transformed into some higher spiritual being.
(See “Alchemy Ancient and Modern,” by H. Stanley Redgrove; “Alchemy,
Its Scope and Romance,” by the Rev. J. E. Mercer, etc.) Mr. Foster
Damon has lately published a series of articles in which he has brought
forward a mass of evidence tending to prove that the alchemists were
also deep students of psychic phenomena, and that their experiments
relative to the “First Matter” were really experiments in so-called
“Materialization!” He has published his findings in a series of
articles in the “Occult Review.”
MODERN CHEMISTRY
Modern chemistry may be said to begin with Robert Boyle (1626–1691).
He defined an element as a substance which could not be decomposed,
but which could enter into combination with other elements, giving
compounds capable of decomposition into these original elements. The
number of elements which were thought to exist varied greatly,--some
contending that they were but few in number, others that they were
numerous. It must be remembered that all this was before the time
of Dalton, and that the atomic theory had not yet been advanced as
a scientific hypothesis, since the days of the ancient Greeks, when
Democritus and Epicurus had defended this view. The swing of science,
at that time was, therefore, toward the materialism of those older
writers, and the atomic theories which they had then proposed.
Chemistry is that branch of science which investigates the nature
and properties of matter in all its forms. It is, perhaps, the most
materialistic of all the sciences, since it deals essentially with
matter. Physics deals with forces or energies, or the energies
manifested by and through matter, but the two are more or less
inter-related--especially of late years, as we shall see. Chemistry is
essentially an _experimental_ science, and practically everything which
has been learned about it has been acquired by means of laboratory
experimentation. But here as elsewhere theories have woven together the
mass of separate facts, and of them made a consistent and philosophical
science.
There are two main divisions of chemistry--inorganic and organic;
that is to say, the chemistry of “dead” matter, and the chemistry
of “living” or organic substances. Chemical experiments may be for
the purpose of _analysis_--discovering the constituents of a given
substance; _synthesis_, in which a compound substance is “created” from
several simpler ones; or purely _experimental_, in which certain tests
are made, and the results or reäctions noted.
MEDIAEVAL CHEMISTRY
As before stated, Chemistry is more or less the direct child of
Alchemy; but before the modern, scientific period of chemical research
had been reached, two transitional stages were first of all passed
through. These were (1) The so-called “Iatro-Chemical” period--the
period of medical mysticism; and (2) the “phlogistic” period. A few
words will be necessary to explain each of these terms, and the period
of chemical development which they covered.
As may be inferred from the name, the iatro-chemical period was one
in which attempts were made to combine chemistry and medicine, and
make the former serve the latter. All kinds of weird concoctions were
tried, and attempts were made to explain, on chemical principles, all
the changes and reactions occurring in the body--an attempt which
was necessarily futile for the chemistry of that day. However, many
important results were achieved, as the consequence of experimentation,
and chemical science was on the whole enriched, even though the
workers of that day were inspired by totally erroneous views.
The Phlogistic Period takes its name from a hypothetical substance
denominated “phlogiston.” This was supposed to be an invisible
principle or entity, constituting the basis of Fire, and corresponds to
the “pure fire” of Zoroaster. The Phlogiston theory was propounded and
championed by Stahl, and it was defined by him as follows:
“Phlogiston is ... a very subtle matter, capable of penetrating the
most dense substances; it neither burns, nor glows, nor is visible; it
is agitated by an igneous motion, and it is capable of communicating
its motion to material particles apt to receive it. The particles when
indued with this rapid motion constitute visible fire....”
This conception dominated the whole scientific world for many
years. The experimental work undertaken by Scheele and Priestly,
however, finally enabled Lavoisier to discover the true nature
of “fire”--combustion. In a famous “Memoir,” published in 1783,
entitled “Reflections Concerning Phlogiston,” he showed that all the
observed phenomena could be accounted for without the presence of any
hypothetical phlogiston; in fact, as he himself says, they “can be
better explained without phlogiston than by means of it.” His discovery
of oxygen, in the atmosphere, was a fundamentally important step in
modern chemical science. Hitherto, the air was thought to be a single
gas, or a mixture of various gases; but oxygen was unknown as its most
important constituent. Lavoisier’s discovery finally disposed of the
phlogiston idea, and ushered in the new era of scientific chemistry.
It may be thought that undue space has been devoted to this theory of
Phlogiston; but anyone reading the history of Chemistry will realize
the extent to which this idea completely dominated the minds of men at
that time, and how all chemical researches were perverted by it. The
discovery of the true nature of combustion was one of the fundamental
turning-points in the history of scientific thought.
The material world in which we live is very evidently composed of a
variety of substances. At least some of these were soon seen to exist
in at least three different states--solid, liquid and gaseous. These
seemed to differ radically from one another; ice, water and steam are
as different as one can imagine; and yet, somehow, they were the same
thing after all; for ice melts and becomes water, and water, when
heated, becomes steam. On the contrary, steam cools and becomes water
again, and when it is sufficiently cold, will again form ice. There
must be some fundamental Thing, therefore, of which water is composed.
What is this Thing? How many such Things are there in the world? Are
there a limitless number, or only a few? If a certain, limited number,
how many? And how discover them? These were questions which naturally
occupied the minds of men throughout the ages. No answer was found,
however, and it remained for John Dalton to discover and formulate the
Law which enabled men to obtain their first glimpse of the nature of
the ultimate constitution of matter.
JOHN DALTON
John Dalton (1766–1844) was born in Eaglesfield, in Cumberland
(England), and was the son of a poor weaver. Endowed with natural
aptitude and an indomitable will, he utilized all possible
opportunities for the study of mathematics and natural philosophy.
He taught school, while devoting all his spare time to his beloved
scientific researches. In fact, he earned his living as a private
teacher to the end of his life, never having enough money to pursue his
investigations unhampered by material considerations.
It was, of course, well known that mere _mixtures_ were entirely
different things from chemical _compounds_. We can mix sand and sugar
together, but they remain sand and sugar, and can be separated again,
having undergone no change. Or we can mix together two liquids or
two gases, and they also can again be separated by suitable means.
But when two substances chemically combine one with another, then we
have some third thing which is entirely different from the original
two, and which possesses properties dissimilar from either. Now, what
has happened when substances thus combine? What are the laws of such
combinations? And what are the ultimate constituents of matter, which
render these combinations possible? Dalton was the first to undertake
an explanation of these phenomena, backed up by experimental evidence.
The historic importance of this cannot be overestimated. As Dr. Raphael
Meldola says, in his “Chemistry”:--
“The doctrine of equivalence, even in its most elastic form, is still
nothing more than a quantitative expression of the facts of chemical
composition. Of course, there must be some underlying principle--some
explanation of this simplicity of multiplicity. Such explanation was
first definitely formulated in 1807-08 by John Dalton, who not only
discovered the law of Multiple Proportions, but suggested a theory, the
introduction of which marks one of the greatest epochs in the history
of Chemistry. The reason why combination takes place in definite
proportions by weight, and why, when the same element has more than
one equivalent the principle of integral multiples is maintained
is, according to Dalton’s explanation, because the combination is
between the ultimate particles of which elementary matter is composed.
This is the notion of the discontinuity or discreteness of matter.
The “particles” of which matter is composed--whatever its state of
aggregation--are, from Dalton’s point of view, ultimate in the sense of
being indivisible. For this reason he called them _atoms_.”
THE ATOMIC THEORY
Here, then, we have at last the Atomic Theory--the theory, that is,
that all matter, in all its stages, is built-up of extremely small
particles which are so small, indeed, that they can no longer be
sub-divided. They are the ultimate of matter--the “building stones of
the Universe”--of which everything, animate and inanimate, is composed.
These atoms were held to be spherical in shape, of a certain definite
weight and figure, according to the element or substance in question.
Thus: “every particle of water is like every other particle of water,
every particle of hydrogen is like every other particle of hydrogen,
etc.” These ultimate particles--atoms--were held to be indestructible.
These atoms all had their own particular _weights_, which might be
denoted by number. Hence “atomic weight.”
These atoms, then, combine, forming molecules, or compounds of atoms;
and molecules make up matter as we see and know it.
Further, most of the matter in the world is composed of a variety of
elementary substances, limited in number. When more complex bodies
are analyzed or broken-down, these elementary substances are always
found. The number of those in Dalton’s day was unknown; but they had
long been known as _elements_. Elements were, of course, composed of
their own particular atoms; while all other substances were made-up of
combinations of elements.
THE ELEMENTS
Dalton’s views ushered in a new era in chemistry. Prolonged researches
were at once undertaken, in order to determine the precise atomic
weights--investigations which are being carried on even today. The
exact size, shape, texture, etc., of the atom was subject to endless
investigation. The nature of chemical combinations (how two elements
combine with one another) held the fascinated attention of chemists
for a hundred years, and it is only within the past few years that
a definite solution has been found, and this has only been rendered
possible by the newer views of matter, entirely different from those
maintained during the past century.
During the hundred years which have elapsed since Dalton’s time, a
number of new elements have been discovered, and there are reasons for
supposing that there are some yet to discover. It is now believed,
however, that there are 92 primary elements, of which Hydrogen has the
lowest atomic weight, and Uranium the highest. Typical elements are:
Oxygen, Iron, Fluorine, Silver, Sodium, Sulphur, Gold, Zinc, Copper,
etc. A complete list may be found in any standard Chemistry.
ATOMIC WEIGHTS
When work was undertaken, to discover the exact atomic weights of these
various elements, it was soon found that these could not be expressed
in _exact_, whole numbers. Fractions or decimal numbers were nearly
always found to exist. Thus, the atomic weight of Hydrogen was not
exactly 1, but 1.008; copper was 63.57, etc. For long it was thought
that these variations were due to errors of experiment, and renewed
attempts were made to reach more accurate conclusions, in which these
apparently annoying fractions were absent. But the most painstaking
experimental work only served to confirm these results, and still later
researches have shown us _why_ this is so. It would take us too far
afield, however, to go into that question at present.
The various elements were given symbols for the sake of brevity; some
of these represented the first letters of the name of the element;
some were the first letters of the Latin word for that element. Thus,
Co = Cobalt, S = Sulphur, Ne = Neon, Bi = Bismuth. On the other hand,
Fe = Iron (Latin, ferrum), etc. This served greatly to abbreviate
chemical language, and at the same time simplified chemical formulæ and
equations.
VALENCY
We must now explain one or two terms which are extremely important
for understanding what is to follow. The first of these is _Valency_.
We know that chemical combinations take place in fixed proportions
by weight; this is known as the “Constancy of Composition.” There is
always an equivalence noted. This doctrine of equivalence is merely
the numerical expression of the definiteness of chemical change.
Calculations are made from the point-of-view of combining with a
unit-weight of hydrogen (the Unit element). In chemical compounds,
then, the doctrine of equivalence says that these atomic weights
represent quantities of different elementary substances which are of
the same chemical value as measured by their capacity for displacing
the same weight of hydrogen.
A new property of the atom is thus brought out, _viz._, its value
as measured by the number of atoms with which it can combine. This
property is appropriately described as the “Valency” of the atom.
If the atomic weight contains the equivalent once, _i. e._, if the
equivalent and atomic weight are identical, that atom can combine only
with one atom of hydrogen, or of chlorine, bromine, etc. The formulæ of
the compounds, HCl, HBr, etc., expresses this fact. If the equivalent
is contained twice in the atomic weight, then that atom can obviously
combine with two atoms of hydrogen, chlorine, etc.; if it is contained
three times in the atomic weight, the combining capacity or valency of
the atom is three; and so forth.
THE PERIODIC LAW
The work which had been done upon the atomic weights rendered possible
one of the most brilliant generalizations of modern times, in this
field. This was the _Periodic Law_. In the year 1864, Newlands
published a Table containing the various elements arranged in the order
of their atomic weights. In a side column the differences between these
weights were given, each being deducted from the one next higher in the
scale. The next year, Newlands announced his “law of octaves,” which
he deduced from his arrangement of the elements. He said in part that:
“If the elements are arranged in the order of their equivalents, with
a few slight transpositions ... it will be observed that elements,
belonging to the same group usually appear on the same horizontal
line.... It will also be seen that the number of analogous elements
generally differ either by seven or by some multiple of seven; in
other words, members of the same group stand to each other in the same
relation as the extremities of one or more octaves in music.”
This pioneer work of Newlands rendered possible the Periodic Law, as
finally formulated and worked out in detail by Mendeleeff. Briefly, the
Law states that “the properties of an element are a periodic function
of its atomic weight.”
This is merely another way of saying that if you know the atomic weight
of an element, you also know its properties, since these are fixed
or invariable. Mendeleeff arranged the elements in various “Groups,”
according to their atomic weights, and it was found that the properties
of the elements periodically recur as the weights of the atoms rise.
There were certain empty spaces in Mendeleeff’s Table, waiting for new
elements which should fit into these empty spaces, if discovered. At
the time they had not been discovered; but several of them have been
since, and it is a remarkable fact that they invariably fit into his
table exhibiting all the properties which they should theoretically
exhibit, and might have been predicted to, years before. This is one of
the surest confirmations of the accuracy of Mendeleeff’s general Law,
and is one of the finest generalizations ever made in science.
The conclusion which we may draw from this Law is that there is a
definite _relationship_ between the chemical elements. How or why
this relationship existed was not known at the time, and only became
clear half a century later, when the newer discoveries concerning the
ultimate constitution of matter rendered this clear.
EARLIER DISCOVERIES
Mendeleeff’s Law could not have been formulated had not an immense
amount of research work preceded it, and a number of new elements been
discovered. Such was, however, the case. Immediately following the
great work of Lavoisier, a host of brilliant chemists appeared, and
rapid and important advances were made in consequence. Cadmium was
discovered by Stromeyer in 1817; lithium in the same year by Arfvedson.
Silicon was isolated in 1810 by Berzelius. In 1827, Wohler isolated
aluminum; and the same scientist also isolated beryllium the following
year. Bromine was discovered by Balard in 1826; iodine, in 1811, by
Courtois. Tellurium had been discovered by Muller von Reichenstein
in 1782; Berzelius discovered an element closely analogous to
it--selenium--in 1817. Elements continued to be added to the list--and
then no more! Had every element been discovered? Some were inclined to
think so. With the discovery of Radium, by the Curies, however, another
whole list of elements was brought to light--all of which have been
added to the Table of the Periodic Law.
Meanwhile, further discoveries of the curious properties of matter
were being made. For example, it had been noticed that at least three
distinct varieties of sulphur existed: (1) A pale yellow, brittle
solid; (2) translucent needles; and (3) soft and rubber-like sulphur.
These were all different physical varieties of one and the same
substance--nevertheless they are all sulphur! This element, then, can
assume more than one form, and because of this, the term “allotropic”
has been applied, to signify the varieties of appearance which the same
substance can be made to assume. A good example of this afforded by
charcoal, graphite (or black-lead) and diamond,--which would hardly be
suspected of being all the same substance; and yet they are!
ANALYSIS AND SYNTHESIS
Compounds may be broken up into their constituents, during the process
of analysis, or they may be made to combine one with another, in
synthesis. All the resources of modern science have been brought to
bear, in efforts to effect these various alterations or changes. Great
heat, extreme cold, chemical reägents, enormous pressures, high vacua,
electrical currents and sparks, bombardment with radio-activity,
etc.--all have been employed in these chemical investigations. Suitable
laboratories have been constructed, encasing immense boilers, huge
refrigeration machines, electrical contrivances of all kinds, etc.
What tremendous strides have been made in this field during the past
century--from the simple glass retorts, flasks and apparatus of a
century ago! But this only shows us how tremendous would be our
progress could men but learn to work together, in harmony, welded
together by a common interest,--instead of butchering one another, or
wasting their precious lives and energies in scandals and political
intrigues!
But let us return to earth again--to matter--the subject of chemistry!
FORMULAE AND EQUATIONS
We have seen that the various chemical elements combine with one
another in certain proportions. In order to express these varied
reactions, chemical formulæ have been devised, which can be read at
a glance, showing the changes which have taken place in any given
combination. When one atom of one element combines with one atom of
another, the letters signifying these elements are simply written side
by side, thus: HCl. When, however, two atoms of one element combine
with one of another, a small figure is placed under and to the right
of the element, thus: H₂O. Here we see at a glance that two atoms of
hydrogen have combined with one of oxygen, forming water. This is
the simplest type of formula, and is often known as the _empirical_
formula. There is, however, another way of writing a formula, which is
more expressive, thus:
B
A=C=
B
This is known as a _structural_ or _constitutional_ formula, and from
it we can see at a glance that A is bivalent, C is quadrivalent, and B
univalent. This type of formula shows us more readily than the other
the structure of the molecule in question. The complexity of such
formulæ naturally increases with the complexity of the molecules, and
in many cases may be extremely intricate. Ordinary chemical formulæ,
however, are written empirically. Any chemical changes which take place
as the result of some reaction are expressed in this manner.
ORGANIC VS. INORGANIC CHEMISTRY
As before stated, chemistry has been divided into two
categories--organic and inorganic. It was stated at the time that
these divisions represented the chemistry of living and dead matter,
respectively. As a matter-of-fact, this description is not quite
accurate. This was the older view of the observed facts, because it
was believed that some mysterious “vitality” was responsible for the
peculiar substances found in living bodies, but the chemist has now
succeeded in making, in the laboratory, a number of these substances
which were thought to be the result of life only; and in addition has
succeeded in making great numbers of organic compounds not found in
the living body. Over 150,000 “organic” compounds are now known to the
chemist, only a small fraction of which are known to be the product of
“vitality.” All living things--animal and vegetable--contain carbon,
as their most important constituent, so that the modern view of
organic chemistry is that it is, very largely, the chemistry of carbon
compounds. Whether or not any form of “vitality” exists aside from the
living matter studied is a question usually passed over by chemists as
beyond their province.
There is no doubt, however, that the human body presents many problems
still unexplained by modern chemistry. Take, for example, the miracle
of digestion. A potato, a cabbage, an apple, a chicken running about
the yard, a piece of candy--all these are eaten by little Mary Jones,
and are somehow turned into the body of little Mary Jones, making
hair, teeth, eyes, lungs, liver, nerves, brain, etc. The food material
is somehow transformed into the living body of the person eating
it! Much has been discovered as to the innumerable changes which
the food undergoes during the various stages of digestion, but the
final result--how this pabulum is converted into bodily tissue--is
still largely a mystery. We know, for example, that proteins are
broken-up into simpler compounds, the most important of which are the
amino-acids. Fats are broken up into fatty acids and glycerine, and
substances resembling soaps are formed in the body. Carbohydrates are
resolved into levulose, glucose, maltose, etc., which are utilizable
by the human system. But just how these substances are converted into
bodily tissue is still largely a problem.
ORGANIC COMPOUNDS
The living matter of the body is composed of a variety of substances,
of which protoplasm may be taken as typical. This is highly complex,
and while it can be imitated by the chemist, its living properties have
not been reproduced. (See my book on “Life: Its Origin and Nature,” in
the present series.) The various secretions and excretions of the body
have been studied exhaustively by physiological chemists. _Plants_ have
also been studied minutely from a similar point-of-view.
A number of important discoveries have resulted from this work,
however, and nearly all the essential animal and vegetable substances
are at present accessible to artificial synthesis from their very
elements. Even protein matter seems to have lost much of its mystery
since we have learned from Emil Fischer’s work that amino-acids can
be combined in the same way as they occur in protein. Compounds of
Amino-acids can be obtained, which show all the main reactions of
protein substances. Emil Fischer, of Berlin, was the same chemist
who, in 1886, discovered how to prepare grape-sugar from glycerine.
A considerable number of plant alkaloids have also been artificially
prepared in the course of the last five or six decades. The most
important coloring matters of plants--for instance, alizarin and
indigotin,--are no longer extracted from plants for technical
purposes, but are accessible from the products of coal-tar.
CATALYSIS
We now come to a remarkable series of chemical phenomena, which have
been much studied during the past century, and which have a bearing
upon both organic and inorganic chemistry. More than a century ago,
it was discovered that certain chemical substances, which will not
normally combine with one another, can be made to do so, if another
substance is brought into contact with them. This third substance does
not in any way enter into the combination, or share in the reaction;
its mere presence seems to bring it about. Thus, oxygen and hydrogen
may be mixed together; but if a small amount of “platinum black” be
introduced, an explosion of the gases at once occurs. Hydroperoxide
is rapidly split into oxygen and water when in contact with “platinum
black,” etc. These contact-effects are very curious, and have engaged
the attention of chemists for a long time. Berzelius is responsible for
the term now generally used--_catalysis_. We now speak of catalytic
power, catalytic reactions, and so forth.
These catalytic reäctions soon became very important factors in organic
chemistry and biology, as well as in the field of inorganic chemistry.
In 1833, Payen and Persoz in Paris made the discovery that germinating
seeds contain a peculiar contact-substance, which transforms starch
into sugar. This substance they named _Diastase_. Similar effects were
noted to occur elsewhere,--particularly in the protein digestion in
the stomach of man and the higher animals. We now know that many such
reäctions occur in the living cells, and the chemical phenomena of life
have had an entirely new light thrown upon them by these findings.
ENZYMES
They led, in short, to the discovery of the so-called _Enzymes_.
Until relatively recently, the expression “Ferment” was used, as the
phenomena were akin to fermentation. Soluble ferments are termed
Enzymes, and the phenomena connected with living protoplasm are now
known to be largely due to the action of a group of Enzymes. These are
catalytic substances, are of a limited field of action, of colloidal
nature, and very little resistant to heat. When injected into the
veins of animals, other substances are at once manufactured, which
have been called “anti-enzymes,” which have the effect of offsetting
their action. Sunlight and ultra-violet light destroy enzymes. Their
importance in the field of biology may be discerned when it is stated
that researches have shown us that, _e. g._, the amount of protein
digested in a certain time is not proportional to the quantity of the
enzyme itself, but to the square root of the quantity of the enzyme.
HORMONES
These enzymes must not be confused with other internal secretions, such
as the _hormones_. These are substances generated by the so-called
ductless glands,--such as the thyroid, the pituitary, the adrenals,
etc. These ductless glands secrete substances which when absorbed into
the blood-stream greatly affect the life of the body, its functions,
its structure and its growth, and to a certain extent at least the
mental life. Researches in this field are of relatively recent origin,
but of extreme importance. I have mentioned this subject at greater
length in my little book on “Life: Its Origin and Nature,” in the
present series, and the interested reader may refer to such a work as
Dr. Louis Berman’s “The Glands Regulating Personality,” for further
details.
There is no matter anywhere in the universe, living or dead, which
modern chemistry does not attempt to analyze. Not only in the
laboratory are these tests undertaken, with minute particles of matter.
The very earth on which we dwell has been subjected to chemical
analysis, and so have the stars, the planets and suns which circle
around us in space,--perhaps separated from us by many millions
of miles. The ability to do this is assuredly one of the greatest
achievements of the mind of man, and represents one of the greatest
conquests over nature, over time and space.
CHEMISTRY OF THE EARTH
The water constituting our seas, lakes, rivers and oceans; the air
constituting our atmosphere; the materials of the earth on which we
dwell--clay, rock, mud, granite, metals--all have been analyzed,
and their chemical composition accurately determined. It has even
been possible to measure the density and weight of our earth, and to
calculate its age, from the salinity of its oceans. (Of this more
anon.) But when it comes to ascertaining with great accuracy the
chemical constitution of distant stars, _that_ seems a feat well-nigh
impossible, and unless the process by means of which it is accomplished
were explained, it might very well be disbelieved.
How, then, can this be accomplished?
For our explanation, we must go back to a classical experiment made
by Sir Isaac Newton. He proved that white light, when made to pass
through a glass prism, is split up into a variety of colors. There are
seven primary colors, constituting the visible spectrum. These are red,
orange, yellow, green, blue, indigo and violet. We now know that there
are both “ultra-violet” and “infra-red” rays, invisible to the eye,
above and below the spectrum, but this was not known until long after.
The essential fact is that light, when passed through a prism, is split
up into its primary colors.
THE SPECTROSCOPE
The instruments employed were necessarily soon refined, and the modern
“spectroscope” resulted,--a piece of apparatus of great delicacy,
capable of studying these effects with exactitude.
The function of the spectroscope is to receive a sample of light and
to separate its different components. In a broad sense, everything
that can be seen has a spectrum--flame, blue sky, red hot metal, the
sun, the electric spark, etc. We can at once divide these things
into two classes, (1) those that are visible because they emit light
of their own; (2) those that can be seen only by virtue of their
reflecting, diffusing or transmitting light that falls upon them from
other sources. The former are called “emission spectra” and the latter
“absorption spectra.”
Now, when practically any spectrum be examined in this way, it will
be seen that certain bands of shadow, or dark lines, cut across the
light spectrum, in absorption spectra, these are the things which
are studied. Thus, when we observe the spectrum of the sun, or of
many of the stars, we find that the spectrum may be described as a
continuous spectrum, from which a number of narrow lines are omitted.
The lines consequently appear dark on a bright ground. These are called
“absorption lines.”
Just why these dark lines appear would take us too far afield to
explain here; suffice it to say that every chemical element has been
found to yield a different spectrum; that is to say, the number and
arrangement of these dark lines will indicate the presence of the
element in question. Whenever certain lines appear on the spectrum, we
may be sure that such-and-such an element is present. Thus, Kirchhoff
first proved that two of these dark lines were caused by the white
light of the solar photosphere having suffered absorption at the
sun, by passing through a stratum of glowing sodium vapor. Sodium was
thus shown to be present in the sun. Other elements were similarly
identified, not only in the sun, but in the millions of stars in the
heavens. By means of spectrum analysis, therefore, it has been possible
to detect and identify the various chemical elements present in any
given sun or star in space.
ASTRO-PHYSICS AND CHEMISTRY
In this manner, about forty terrestrial elements have been shown to
exist in the sun. Carbon, oxygen, iron, silicon, nickel, etc., exist in
the sun just as they do on our earth. On the other hand, many elements,
such as mercury, nitrogen, sulphur, and boron do not appear, although
they are found in abundance on the earth. Yet several elements were
shown to exist in the sun which up to that time had not been discovered
here. Helium is an example. (From the Greek, _Helios_, the Sun). And
yet, when attention was directed to this element, it was soon found
in our earth, and is today so common that helium gas is employed
to inflate balloons, in preference to hydrogen, on account of its
non-combustibility.
SPECTRUM ANALYSIS
Spectrum analysis, then, tells us the precise chemical constitution of
the various suns, or stars, in space, and it also tells us that these
stars are incapable of supporting life such as we know it. As Dr. E.
Walter Maunder says, in his book, “Are the Planets Inhabited?”:
“The application of the spectroscope to astronomy is not confined
to the sun, but reaches much further. The stars also yield their
spectra, and we are compelled to recognize that they also are suns;
intensely heated globes of glowing gas, rich in the same elements as
those familiar to us on the Earth and known by their spectral lines
to be present on the sun. The stars, therefore, cannot themselves be
inhabited worlds any more than the sun, and at a stroke the whole of
the celestial luminaries within the furthest range of our most powerful
telescopes are removed from our present search (_i. e._, whether or
not life may exist upon them). Only those members of our solar system
that shine by reflecting the light of the sun can be cool enough for
habitation, the true stars cannot be inhabited, for, whatever their
quality and order, they are all suns, and must necessarily be in far
too highly heated a condition to be the abode of life. Many of them
may, perhaps, be a source of light and heat to attendant planets, but
there is no single instance in which such a planet has been directly
observed; no dark, non-luminous body has ever been actually seen in
attendance on a star. Many double or multiple stars are known, but
these are all instances in which one sun-like body is revolving round
another of the same order. We see no body shining by reflected light
outside the limits of the solar system. Planets to the various stars
may exist in countless numbers, but they are invisible to us....”
Thus has the science of chemistry been wafted across hundreds of
millions of miles of space, and has enabled us to tell, not only the
composition of these distant bodies, but also the degree of their
habitability, and their possible sources as abodes of life.
INDUSTRIAL CHEMISTRY
But if all this is of purely theoretical interest, the chemistry of our
earth and its products is of immense practical importance. It may be
_applied_, and the day of “industrial chemistry” is here. By studying
the chemistry of soils, the farmer has been enabled to increase both
the quality and the quantity of his crops. By employing artificial
fertilizers, production has been greatly increased. An analysis of
the earth’s strata has thrown great light upon geology. Analytical
chemistry has proved of service in criminology,--by enabling experts
to detect poisons, blood-stains, etc. (Unfortunately, it has also
been applied detrimentally, in the manufacture of explosives, poison
gases, etc., employed in war.) Dentistry and surgery have been rendered
painless by the discovery of anæsthetics. The wholesale manufacture of
illuminating gas has been instrumental in lighting millions of homes.
The manufacture of steel, paper, ink, dyes, stains, paints, perfumes,
bread, and a thousand-and-one useful articles of our daily lives has
been rendered possible by the progress of chemical research. Artificial
preservatives have enabled us to keep food-stuffs for long periods of
time. By the discovery of the nature of iron rust, bridges, buildings,
etc., have been preserved intact. Our food, our clothes, our very lives
themselves, may be said to depend upon modern chemistry for their
maintenance and preservation.
Let us pass in rapid summary a few of these results. Let us take, for
example, _glass_.
Glass is made from silica. What is silica? It is a substance of
remarkable infusibility, and is the oxide of silicon, which is a
near neighbor of carbon. Glass is made by mixing sand, limestone and
carbonate of soda or potash in large pots, and melting them together at
a temperature of 3,500° F. The sand, being silica, combines with the
lime of the carbonate of lime, to give silicate of lime, and with the
soda (or potash) of the carbonate of soda (or potash) to give silicate
or soda (or potash). These two silicates become intimately fused and
form the glass, which remains liquid in the pot. It is then blown into
various shapes or rolled into thin sheets for window glass. We know
what an effect windows have had upon the comforts of modern life!
By mixing together several metals, _alloys_ are obtained which very
often have properties quite different from those of the substances
which compose them. Thus: Bronze is a mixture of copper and tin;
plumber’s solder is an alloy of lead and tin; brass is an alloy of
copper and zinc; ferro-silicon is a union of silicon and iron, etc.
Many of these alloys are of great utility in the various arts and
sciences, as well as in manufacture.
Gilding, silvering and electroplating have been rendered possible by
modern chemistry. Alumina and porcelain have been produced. Alumina
is the oxide of aluminum. One variety of clay known as “kaolin” is
employed in the manufacture of porcelain. China and earthenware are
made by very similar processes. Alcohol, wine and beer have depended
upon scientific chemistry for their production. Ice can be manufactured
artificially by means of freezing mixtures. The manufacture of oxygen
gas has rendered possible high altitude flights by aviators. Camphor
can now be manufactured, instead of depending upon nature’s resources
for this valuable substance. Wood-pulp, starch and sugar owe much to
modern chemistry. Artificial silk is manufactured on a large scale.
Soaps and fats have likewise been developed in vast quantities. The
perfume milady uses has been developed by the chemist. Colors and dyes
now constitute an enormous industry. For our medicines we depend upon
the chemist, when visiting the nearest drug store. These are but a few
examples, which might be lengthened almost indefinitely, illustrating
the extent to which we are dependent upon modern chemistry, in our
daily lives.
And chemistry is capable of explaining many things which would be
unintelligible without its aid. Let us take a simple example by way
of illustration. You have probably noticed that a frozen potato has
a characteristic sugary taste. The cause of it is this: the potato
contains in its tissues a great quantity of starch, as well as a
diastase capable of transforming this starch at the moment of its
sprouting. These two substances are kept apart by the membrane of
the tissue. But if a frost occurs, the ice tears this membrane, and
the starch comes in contact with this diastase and is, therefore,
transformed into sugar, just as it is when the sprouting of the potato
begins.
INSTRUMENTS OF RESEARCH
These applications of chemistry have been rendered possible by improved
methods of investigation, a greater knowledge of the nature of matter
itself, and the perfection of scientific instruments of precision.
These instruments are so much finer and more delicate than our senses
that they have been the means of disclosing the actual constitution
of matter. A man might sit and “meditate” upon the nature of matter
for years, but he would be no nearer an actual _proof_ as to its
constitution than he was at the beginning. It is generally conceded
that Aristotle possessed one of the finest minds the world has ever
known; yet any school boy today knows more of the ultimate constitution
of matter than did Aristotle. The reason for this is that instrumental
methods of research have enabled us to see and measure the ultimate
properties of matter,--which our unaided senses would never permit
us to do. The development of science in other fields, therefore, has
rendered possible the rapid growth of chemistry, during the past
century; and chemistry, in turn, has assisted the other sciences. Thus
does all knowledge work hand in hand, when co-operation is rendered
possible!
SALINITY OF THE OCEANS
I referred some time ago to the calculations which had been made as to
the age of the earth, based upon researches as to the salinity of the
ocean. As we know, the water of all the oceans is salt water; only that
of rivers and lakes is “fresh.” But the degree of the ocean’s saltness
is not quite constant. It varies, since evaporation is constantly
taking place; sediments are deposited; and above all vast quantities of
water are being poured into the ocean by the hundreds of rivers which
flow into it, carrying all kinds of earthy deposits which have been
washed away by their passage through the river-beds over which they
flow.
In 1715, the famous astronomer Edmund Halley published a paper entitled
“A Short Account of the Saltness of the Ocean.... With a Proposal by
Help Thereof to Discover the Age of the World.” No definite progress
was made, however, until 1899, when Joly pointed out that of the many
elements which enter into the composition of salt water, sodium alone
tends to accumulate. All the others are sooner or later rejected,
associating themselves with the detrital sediments, or forming chemical
or organic sediments by their ultimate precipitation. He accordingly
used sodium as the index of the age of the oceans. He assumed that the
annual increase of sodium has been more or less constant, being added
to every year by the quantity washed into the ocean by the rivers. How
long a period of time would it require to reach its present degree
of saltness? Taking all the oceans as one, the volume of the ocean
is approximately 320,000,000 cubic miles. Its density (according to
Murray) is 1.026. On the basis of these figures, Joly, and after
him Sollas and others, calculated that it would require from 80 to
150 million years for the present degree of salinity to be reached.
Ninety or a hundred million years would be a fair estimate. Indirectly
therefore, the study of the salinity of the oceans has thrown light
upon the age of our earth, and its chemical constitution throughout
geological ages.
THE NEWER CHEMISTRY
It will be seen, therefore, that chemistry has not only proved of the
utmost practical value to mankind, but that it has been instrumental
in solving some of the greatest enigmas confronting the mind of man,
and in settling some philosophical and even theological questions.
(The age of the earth, the composition and habitability of distant
stars, etc.) Attempts have been made to account for life itself along
purely physico-chemical lines. And all this was attempted--and in part
even rendered possible--before the ultimate constitution of matter was
known! During the present generation, an entirely new light has been
thrown upon this central problem, and the ideas of centuries have been
discarded. Let us trace the final steps of research in this direction,
and see how the latest findings of modern science have thrown light
upon the world-old problem of the ultimate constitution of matter.
RADIO-ACTIVITY
We saw at the very beginning of this little book that, from time
immemorial, something corresponding to Atoms were regarded as the
ultimate “building stones” of the universe--tiny particles, incapable
of diversion, beyond which it was impossible to go. Beginning with
Epicurus and Democritus, this idea took scientific form; it was held by
many philosophers throughout the ages; it formed the basis of Dalton’s
atomic theory, and was assumed by the Periodic Law. It was not until
the last years of the preceding century that this idea was called into
question. The discovery of _radium_, by the Curies, caused a sensation
in the scientific world. How account for the phenomena observed? Radium
seemed to give off energy continuously, without losing any; heat was
constantly being radiated without lessening the original amount. Had
the secret of perpetual motion been discovered? What was happening? The
discovery of other radio-active elements only tended to increase the
problem, instead of solving it. Here was some new property of matter,
hitherto unsuspected, going on before the eyes of chemists, which they
could not understand or explain.
INTRA-ATOMIC ENERGY
Professor E. Rutherford, of M’Gill University, Canada, was among the
first to propose a new and startling theory. He said: Suppose that
the atoms are _not_ indivisible? Suppose that they are capable of
being split-up into something still smaller and finer? If the atoms
themselves are being disintegrated, immense quantities of energy would
probably be available--“intra-atomic energy”--which would account
for the results obtained. It is true that we should no longer have
our stable atoms; they would vanish and be represented by something
else. And that “something” would no longer be matter, in the sense
that we now understand it; but we could account for the observed facts
(radio-activity, etc.), and we can then endeavor to discover what
atoms are resolved into later on. This theory was soon proved to be
true; atoms were shown to be divisible, and capable of being split-up
into something still smaller, which were no longer “matter” in the old
sense. Matter, in short, had technically disappeared, and had been
resolved into its component parts. This being so, the question at once
arose: Of what is matter (the atom) composed?
THE THEORY OF MATTER
Without going into great detail, or attempting to trace the history
of the various discoveries which led up to it, it may now be stated
definitely that matter is built-up of _electricity_. For the proof of
this, the scientific world has to thank Sir J. J. Thomson, who first
popularized this view in his book “Electricity and Matter.” He was
closely seconded by Sir Oliver Lodge, Sir William Crookes, and many
other eminent scientists. On this view, matter totally disappears,
as such; it becomes super-sensible; it is resolved into energy.
Electricity and the ether somehow are responsible for matter, but just
_how_ was not at the time understood.
It took many years of patient research to arrive at definite
conclusions; in fact, it may be said that definite conclusions have not
even yet been reached,--though more or less unanimity of opinion exists
as to the structure of atoms. The new theory of matter is that each
atom is built up of negative “electrons,” and positive “protons”--the
former revolving round the latter in orbits analogous to those of our
solar system. The protons, positively charged, remain in the center
of the atom; the electrons, negatively charged, circle about them,
just as our planets circle about the sun. The number of these protons
and electrons varies according to the nature of the element. Hydrogen
representing unity, has but one electron revolving around a single
proton; helium comes next, with two; and so on, up the scale, until
we reach uranium, which has ninety-two. The positive and the negative
charges balance one another in all stable atoms; and when this is not
the case, the atom tends to go to pieces or disintegrate; electrons are
shot off, which join some other atom, and radio-activity results. The
nature of the element itself is accordingly changed, and may even be
so fundamentally changed by this process that it turns into something
else; _i. e._, the transmutation of one element into another has taken
place, as dreamed of by the alchemists! Hence we often hear of the “new
alchemy.” This, in rough outline, is the modern conception of the
atom, and of the constitution of matter generally.
WITHIN THE ATOM
Let us now endeavor to analyze the atom more closely, in the light of
these newer researches. We have seen that the electrons revolve round
the central protons. These protons are probably composed of electrons
and hydrogen nuclei. The total central “sun”--to use the astronomical
analogy--is known as the nucleus. The relative sizes of these bodies
may be appreciated when it is stated that they have been compared to
the sizes of the planets, relative to the distances separating them
from the sun. Vast spaces exist, therefore, within the atom, in which
the electrons revolve. Yet the atoms themselves are inconceivably
small! The following quotation from Bertrand Russell’s “A. B. C. of
Atoms” will perhaps make this clear. He says:
“It will help us to picture the world of atoms if we have, to begin
with, some idea of the size of these units. Let us begin with a gramme
of hydrogen (1/453 of a pound), which is not a very large quantity. How
many atoms will it contain? If the atoms were made up into bundles of
a million-million, and then into a million-million of these bundles,
we should have about a gramme and a half of hydrogen. That is to say,
the weight of one atom of hydrogen is about a million-millionth of
a million-millionth of a gramme and a half. Other atoms weigh more
than the atom of hydrogen, but not enormously more; an atom of oxygen
weighs sixteen times as much, an atom of lead rather more than 200
times as much. _Per contra_, an electron weighs very much less than a
hydrogen atom; it takes about 1,850 electrons to weigh as much as one
hydrogen atom.”
ELECTRONS
The inner rings of electrons give rise to X-rays when they are
disturbed, and it is chiefly by means of X-rays that their constitution
is studied. The nucleus itself is the source of radio-activity.... The
most complex atom known is that of uranium, which has, in its normal
state, 92 electrons revolving round the nucleus, while the nucleus
itself probably consists of 238 hydrogen nuclei and 146 electrons....
Under normal conditions, when the hydrogen atom is unelectrified,
the electron simply continues to go round and round the nucleus,
just as the earth continues to go round and round the sun. The
electron may move in any one of a certain set of orbits, some larger,
some smaller, some circular, some elliptical. But when the atom is
undisturbed, it has a preference for the smallest of the circular
orbits, in which the distance between the nucleus and the electron is
about half a hundred-millionth of a centimetre. It goes round in this
tiny orbit with very great rapidity; in fact its velocity is about a
hundred-and-thirty-fourth of the velocity of light, which is 186,000
miles a second. Thus the electron manages to cover about 1,400 miles in
every second. To do this, it has to go round its tiny orbit about seven
thousand million times in a millionth of a second; that is to say, in
a millionth of a second it has to live through about seven thousand
million of its “years”!
Such figures, such facts, stagger the imagination. The mind of man
cannot really conceive them. And yet we know that they are not
fanciful; calculations and indirect measurements have been made with
the utmost exactitude. And, after all, the infinitely little is no
more staggering than the infinitely great. For in astronomy we know
that stars billions of miles distant from us in space have been seen,
measured, photographed and analyzed. Tens of thousands of “light-years”
separate us from them (_i. e._, space which would be travelled by
light, speeding at 186,000 miles a second). And yet the structure of
the atom closely resembles the planetary system! Is the whole Universe,
great and small, built according to the same plan, according to the
same model? It would appear so!
It will be seen from the above that the modern science of chemistry
overlaps other sciences in many directions--physics, biology,
astronomy, etc. These sciences are to a certain extent now inter-woven
and inter-blended. Where the one ends and the other begins it is hard
to say. Again we see the importance of co-operation in these various
fields of inquiry!
THE NATURE OF MATTER
These newer researches in chemistry have finally enabled us to realize
the ultimate constitution of matter; we have seen that it is composed
of atoms, but these atoms themselves are complex things; they in turn
are composed of electrons, and in the last analysis matter may be said
to be non-existent! It has been resolved into electricity. But this
conception of matter has also enabled us to explain many things before
inexplicable--chemical combination, radio-activity, and what not. The
world-old problem as to the nature of matter has at last been solved.
It now devolves upon the physicist to explain the ultimate nature of
electricity!
Matter, then, in a sense, can dissociate, disintegrate, dematerialize.
It can also integrate, materialize, come into existence. Matter can be
made to vanish and reappear. The old law of the “indestructibility of
matter” is not valid, as generally understood. Matter can be resolved
into energy. And this energy is radiated into space, or converted into
other modes of energy, and finally into heat, which is in turn radiated
into the surrounding medium. The whole universe seems to resemble a
clock, which has been wound-up, and is slowly running down. Even the
law of the “conservation of energy” has been called into question (See
LeBon, “The Evolution of Matter,” and “The Evolution of Forces”). Is
the whole Universe in some mysterious manner also being wound-up? Or
does it move in vast cycles, of alternate action and inaction, as the
Hindu philosophers have always contended? These are ultimate questions
which only the science of the future can solve!