AGRICULTURAL INVENTIONS (_continued_).
When the harvest is ended and the golden stores of grains and fruits are
gathered, then the question arises what shall be next done to prepare
them for food and for shipment to the distant consumer.
If the cleaning of the grain and separating it from the chaff and dirt
are not had in the threshing process, separate machines are employed for
fanning and screening.
It was only during the 18th century that fanning mills were introduced;
and it is related by Sir Walter Scott in one of his novels that some of
his countrymen considered it their religious duty to wait for a natural
wind to separate the chaff from the wheat; that they were greatly
shocked by an invention which would raise a whirlwind in calm weather,
and that they looked upon the use of such a machine as rebellion against
God.
As to the grinding of the grain, the rudimentary means still exist, and
are still used by rudimentary peoples, and to meet exceptional
necessities; these are the primeval hollowed stone and mortar and
pestle, and they too were “the mills of the Gods” in Egyptian, Hebrew
and Early Greek days: the _quern_--that is, the upper running stone and
the lower stationary grooved one--was a later Roman invention and can be
found described only a century or two before the Christian era.
Crude as these means were they were the chief ones used in milling until
within a century and a quarter ago.
In a very recent bright work published in London, by Richard Bennett and
John Elton, on Corn Mills, etc., they say on this point: “The mill of
the last century, that, by which, despite its imperfections, the
production of flour rose from one of the smallest to one of the greatest
and most valuable industries of the world, was essentially a structure
of few parts, whether driven by water or wind, and its processes were
exceedingly simple. The wheat was cleaned by a rude machine consisting
of a couple of cylinders and screens, and an air blast passed through a
pair of mill-stones, running very close together, in order that the
greatest amount of flour might be produced at one grinding. The meal was
then bolted, and the tailings, consisting of bran, middlings and
adherent flour, again sifted and re-ground. It seems probable that the
miller of the time had a fair notion of the high grade of flour ground
from middlings, but no systematic method of procedure for its production
was adopted.”
The upper and the nether mill-stone is still a most useful device. The
“dress,” which consists of the grooves which are formed in the meeting
faces of the stones, has been changed in many ways to meet the
requirements in producing flour in varying degrees of fineness. Machines
have been invented to make such grooves. A Swiss machine for this
purpose consists of two disks carrying diamonds in their peripheries,
which, being put in rapid revolution, cut parallel grooves in the face
of the stone.
A great advance in milling was made both in America and Europe by the
inventions of Oliver Evans. Evans was born in the State of Delaware,
U.S., in 1755, and died in 1819. He was a poor boy and an apprentice to
a wheelwright, and while thus engaged his inventive powers were
developed. He had an idea of a land carriage propelled without animal
power. At the age of 22 he invented a machine for making card teeth,
which superseded the old method of making them by hand. Later he
invented steam-engines and steam-boats, to which attention will
hereafter be called. Entering into business with his brothers within the
period extending from 1785 to 1800, he produced those inventions in
milling which by the opening of the 19th century had revolutionised the
art. A description of the most important of these inventions was
published by him in 1795 in a book entitled _The Young Millwright and
Miller’s Grist_. Patents were granted Evans by the States of Delaware,
Maryland and Pennsylvania in 1787, and by the U.S. Government in 1790
and 1808.
As these inventions formed the basis of the most important subsequent
devices of the century, a brief statement of his system is proper:
From the time the grain was emptied from the waggon to the final
production of the finest flour at the close of the process, all manual
labour was dispensed with. The grain was first emptied into a box hung
on a scale beam where it was weighed, then run into an elevator which
raised it to a chamber over cleaning machines through which it was
passed, and reclaimed by the same means if desired; then it was run down
into a chamber over the hoppers of the mill-stones; when ground it fell
from the mill-stones into conveyors and as carried along subjected to
the heated air of a kiln drier; then carried into a meal elevator to be
raised and dropped on to a cooling floor where it was met by what is
called a hopper boy, consisting of a central round upright shaft
revolving on a pivot, and provided with horizontal arms and sweeps
adapted to be raised and lowered and turned, by which means the meal was
continually stirred around, lifted and turned on the floor and then
gathered on to the bolting hoppers, the bolts being cylindrical sieves
of varying degrees of fineness to separate the flour from its coarser
impurities, and when not bolted sufficiently, carried by a conveyor
called a drill to an elevator to be dumped again into the bolting
hoppers and be re-bolted. When not sufficiently ground the same drill
was used to carry the meal to the grind stones. It was the design of the
process to keep the meal in constant motion from first to last so as to
thoroughly dry and cool it, to heat it further in the meantime, and to
run the machines so slowly as to prevent the rise and waste of the flour
in the form of dust.
The Evans system, with minor modifications and improvements, was the
prevailing one for three-quarters of a century. New mills, when erected,
were provided with this system, and many mills in their quiet retreats
everywhere awoke from their drowsy methods and were equipped with the
new one.
But the whole system of milling has undergone another great change
within the last thirty years:
During that time it has been learned that the coarser portion or kernel
of wheat which lies next to the skin of the berry and between the skin
and the heart is the most valuable and nutritious part, as it consists
largely of gluten, while the interior consists of starch, which when dry
becomes a pearly powder. Under the old systems this coarser part, known
as middlings, was eliminated, and ground for feed for cattle, or into
what was regarded as an inferior grade of flour from which to make
coarse bread. It was customary, therefore, under the old method to set
the grinding surfaces very close with keen sharp burrs, so that this
coarser part was cut off and mixed with the small particles of bran,
fine fuzz and other foreign substances, which was separated from the
finer part of the kernel by the bolting.
The new process consists of removing the outer skin and adherent
impurities from the middlings, then separating the middlings from the
central finer part and then regrinding the middlings into flour.
This middlings flour being superior, as stated, to what was called
straight grade, it became desirable to obtain as much middlings as
possible, and to this end it was necessary to set the grinding surfaces
further apart so as to grind _high_, hence the _high_ milling process as
distinguished from _low_ milling. For the better performance of the high
rolling process, roller mills were invented. It was found that the
cracking process by which the kernel could be cracked and the gluten
middlings separated from the starchy heart could best be had by the
employment of rollers or cylinders in place of face stones, and at the
same time the heating of the product, which injures it, be avoided.
The rollers operate in sets, and successive crackings are obtained by
passing and repassing, if necessary, the grain through these rollers,
set at different distances apart. The operation on grains of different
qualities, whether hard or soft, or containing more or less of the
gluten middlings, or starchy parts, and their minute and graded
separation, thus are obtained with the greatest nicety.
The Hungarians, the Germans, the Austrians, the Swiss, the English and
the Americans have all invented useful forms of these rollers.
This process was accompanied by the invention of new forms of middlings
separators and purifiers, in which upward drafts of air are made to pass
up through flat, graded shaking bolts, in an enclosed case, by which the
bran specks and fuzz are lifted and conveyed away from the shaken
material. In some countries, such as the great wheat state of Minnesota,
U.S., where the wheat had before been of inferior market value owing to
the poorer grade of flour obtained by the old processes, that same wheat
was made to produce the most superior flour under the new processes,
thus increasing the yearly value of the crops by many millions of
dollars.
Disastrous flour dust explosions in some of the great mills at
Minneapolis, in 1877-78, developed the invention of dust collectors, by
which the suspended particles of flour dust are withdrawn from the
machinery and the mill, and the air is cleared for respiration and for
the production of the finest flour, while the mill is kept closed and
comfortable in cold seasons. One of the latest forms of such a collector
has for its essential principle the vertical or rotatory air current,
which it is claimed moves and precipitates the finest particles.
The inventions in the class of mills have so multiplied in these latter
days, that nearly every known article that needs to be cleaned and
hulled, or ground, or cracked or pulverized, has its own specially
designed machine. Wind and water as motive powers have been supplanted
by steam and electricity. It would be impossible in one volume to
describe this great variety. Knight, in his Mechanical Dictionary, gives
a list under “Mills,” of more than a hundred distinct machines and
processes relating to grinding, hulling, crushing, pulverising and
mixing products.
_Vegetable Cutters._--Modern ingenuity has not neglected those more
humble devices which save the drudgery of hand work in the preparation
of vegetables and roots for food for man and beasts, and for use
especially when large quantities are to be prepared. Thus, we find
machines armed with blades and worked by springs and a lever, for
chopping, others for cutting stalks, other machines for paring and
slicing, such as apple and potato parers and slicers, others for grating
and pulping, others for seeding fruits, such as cherries and raisins,
and an entire range of mechanisms, from those which handle delicately
the tenderest pod and smallest seed, to the ponderous machines for
cutting and crushing the cane in sugar making.
_Pressing and Baling._--The want of pressing loose materials and packing
bulky ones, like hay, wool, cotton, hops, etc, and other coarser
products, into small, compact bales and bodies, to facilitate their
transportation, was immediately felt on the great increase of such
products in the century.
From this arose pressing and baling machines of a great variety, until
nearly every agricultural product that can be pressed, packed or baled
has its special machine for that operation. Besides those above
indicated relating to agricultural products, we have cane presses,
cheese presses, butter presses, cigar and tobacco presses, cork presses,
and flour packers, fruit and lard presses, peat presses, sugar presses
and others. Leading mechanical principles in presses are also indicated
by name, as screw presses, toggle presses, beater press, revolving
press, hydraulic press, rack and pinion press, and rolling pressure
press and so on.
There are the presses also that are used in compressing cotton. When it
is remembered that cotton is raised in about twenty different countries,
and that the cotton crop of the United States of 1897-98 was 10,897,857
bales, of about 500 lbs. each; of India, (estimated) for the same
period, 2,844,000, of 400 lbs each; of China about 1,320,000, of 500 lbs
each, and between two and three million bales in the other countries, it
is interesting to consider how the world’s production of this enormous
mass of elastic fibre, amounting to seventeen or eighteen million bales,
of four and five hundred pounds each, is compressed and bound.
The screw press was the earliest form of machine used, and then came the
hydraulic press. Later it has been customary to press the cotton by
screw presses or small hydraulic presses at the plantation, bind it with
ropes or metal bands and then transport it to some central or seaboard
station where an immense establishment exists, provided with a great
steam-operated press, in which the bale from the country is placed and
reduced to one-fourth or one-third its size, and while under pressure
new metallic bands applied, when the bale is ready for shipment. This
was a gain of a remarkable amount of room on shipboard and on cars, and
solved a commercial problem. But now this process, and the commercial
rectangular bale, seem destined to be supplanted by roller presses set
up near the plantations themselves, into which the cotton is fed
directly from the gin, rolled upon itself between the rollers and
compressed into round bales of greater density than the square bale,
thus saving a great amount of cost in dispensing with the steam and
hydraulic plants, with great additional advantages in convenience of
handling and cost of transportation.
It is so arranged also that the cotton may be rolled into clean, uniform
dense layers, so that the same may be unwound at the mill and directly
applied to the machines for its manufacture into fabrics, without the
usual tedious and expensive preliminary operations of combing and
re-rolling.
It has also remained for the developed machine of the century to convert
hay into an export commodity to distant countries by the baling process.
Bale ties themselves have received great attention from inventors, and
the most successful have won fortunes for their owners.
Most ingenious machines have been devised for picking cotton in the
fields, but none have yet reached that stage of perfection sufficient to
supplant the human fingers.
_Fruits and Foods._--To prepare and transport fruits in their natural
state to far distant points, while preserving them from decay for long
times, is, in the large way demanded by the world’s great appetites,
altogether a success of modern invention.
To gather the fruit without bruising by mechanical pickers, and then to
place the fruit, oranges for instance, in the hands of an intelligent
machine which will automatically, but delicately and effectually, wrap
the same in a paper covering, and discharge them without harm, are among
the recent inventive wonders. In the United States alone 67 patents had
been granted up to 1895 for fruit wrapping machines.
Inventions relating to drying and evaporating fruit, and having for
their main object to preserve as much as possible the natural taste and
colour of the fruit, have been numerous. Spreading the fruit in the air
and letting the sun and air do the rest is now a crude process.
These are the general types of drying and evaporating machines:
First, those in which trays of fruit are placed upon stationary ledges
within a heated chamber; second, those in which the trays are raised and
lowered by mechanical means toward or farther from the source of heat as
the drying progresses; third, those in which the fruit is placed in
imperforate steam jacketed pans. Many improvements, of course, have been
made in detail of form, in ventilation, the supplying and regulating of
heat and the moving of trays.
The hermetically sealed glass or earthenware fruit jar, the lids of
which can be screwed or locked down upon a rubber band, after the jar is
filled and the small remainder of air drawn out by a convenient steam
heater, now used by the million, is an illustration of the many useful
modern contrivances in this line.
_Sterilisation._--In preserving, the desirability of preventing disease
and keeping foods in a pure state has developed in the last quarter of a
century many devices by which the food is subjected to a steam heat in
chambers, and, by devices operated from the outside, the cans or bottles
are opened and shut while still within the steam-filled chamber.
_Diastase._--By heating starchy matters with substances containing
diastase, a partial transformation is effected, which will materially
shorten and aid its digestion, and this fact has been largely made use
of in the preparation of soluble foods, especially those designed for
infants and invalids, such as malted milk and lactated food.
_Milkers._--Invention has not only been exercised in the preservation
and transportation of milk, but in the task of milking itself. Since
1860 inventors have been seeking patents for milkers, some having tubes
operated by air-pumps, others on the same principle in which the vacuum
is made to increase and decrease or pulsate, and others for machines in
which the tubes are mechanically contracted by pressure plates.
_Slaughtering._--Great improvements have been made in the slaughtering
of animals, by which a great amount of its repulsiveness and the
unhealthfulness of its surroundings have been removed. These
improvements relate to the construction of proper buildings and
appliances for the handling of the animals, the means for slaughtering,
and modes of taking care of the meat and transporting the same.
Villages, towns, and even many cities, are now relieved of the formerly
unsavoury slaughter-houses, and the work is done from great centres of
supply, where meats in every shape are prepared for food and shipment.
It would be impossible in a bulky volume, much less in a single chapter,
to satisfactorily enumerate those thousands of inventions which, taking
hold of the food products of the earth, have spread them as a feast
before the tribes of men.
_Tobacco._--Some of the best inventive genius of the century has been
exercised in providing for man’s comfort, not a food, but what he
believes to be a solace.
“Sublime Tobacco! which from East to West
Cheers the tar’s labour or the Turkman’s rest.”
In the United States alone, in the year 1885, there were 752,520 acres
of land devoted to the production of tobacco, the amount in pounds grown
being 562,736,000, and the value of which was estimated as $43,265,598.
These amounts have been somewhat less in years since then, but the
appetite continues, and any deficiency in the supply is made up by
enormous importation. Thus, in 1896, there were imported into the United
States, 32,924,966 pounds of tobacco, of various kinds, valued at
$16,503,130. There are no reliable statistics showing that, man for man,
the people of that country are greater lovers of the weed than the
people of other countries, but the annual value of tobacco raised and
imported by them being thus about $60,000,000, it indicates the strength
of the habit and the interest in the nurture of the plant throughout the
world. Neither the “Counterblaste to Tobacco” of King James I., and the
condemnations of kings, popes, priests and sultans, that followed its
early introduction into Europe, served to choke the weed in its infancy
or check its after growth. Now it is attended from the day of its
planting until it reaches the lips of the consumer by contrivances of
consummate skill to fit it for its destined purpose. Besides the
ploughs, the cultivators and the weeders of especial forms used to
cultivate the plant, there are, after the grown plant is cut in the
field, houses of various designs for drying it, machines for rolling the
leaves out smoothly in sheets; machines for removing the stems from the
leaves and for crushing the stem; machines for pressing it into shape,
and for pressing it, whether solid or in granular form, into boxes, tubs
and bags; machines for granulating it and for grinding it into snuff;
machines for twisting it into cords; machines for flavouring the leaf
with saccharine and other matters; machines for making cigars, and
machines of a great variety and of the most ingenious construction for
making cigarettes and putting them in packages.
Samples of pipes made by different ages and by different peoples would
form a collection of wonderful art and ingenuity, second only to an
exhibition of the means and methods of making them.