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CHAPTER V.
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.