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still larger machines, cutting a swath twenty-five or more feet in width and operated by steam power, and doing a correspondingly larger amount of work.
167. Threshing.–In some sections of the country the wheat is mostly threshed directly from the shock, while in other sections it is first stacked or stored in the barn and after the grain has had time to go through the sweat, it is threshed. There is little more danger of the threshed grain heating in the bin if threshed directly from the shock, but where care is taken to have the grain thoroughly dry, heating will not occur. Under such circumstances, there is no material difference in the quality of the grain or of the resulting flour. Probably much of the larger part of the wheat harvested in the United States is threshed directly from the shock. Rainy weather may cause damage, which can be guarded against in some measure by storing in barn or by stacking, but ordinarily it is largely a matter of economy and convenience. The sprouting of wheat not only greatly decreases the quality of the grain, but it has been shown that sprouting wheat for six days or until grains are beginning to burst their first leaf, may cause a loss of twelve per cent in weight. A few farmers own their own threshing machines, and very rarely a machine is permanently located in the barn in accordance with the English custom. Ordinarily, however, the threshing is done by the itinerant steam threshing outfit which does the work for a stated price per bushel. Usually 500 to 1,000 bushels are threshed per day.
168. Storing.–The principal things to be considered in the storing of wheat are the ease of handling, freedom from dampness, insects and vermin. Wheat is not injured by cold, and insects injurious to wheat do not thrive at cold temperatures, consequently the more exposed the granary the better. The larger the bulk of grain and less the exposure of the surface, the less will be the injury from insects. The surface of the rooms and
1 Ark. Bul. 42 (1896), p. 72.
bins should be constructed so as to prevent lodgment of insects, as far as possible, by having smooth surfaces which are preferably
oiled or painted. In order to prevent rats and mice, bins should never be built so that there are air spaces in which these vermin can find hiding places, nor should other objects, such as hay, in which they can find lodgment, be placed against the bins. Wheat in bins made of single
thickness of boards
and fully exposed on Hoa
all sides will never
be seriously injured by rats or mice. Wheat should never be stored in bags where it can be avoided. Granaries that have been in use should be thoroughly cleaned out and treated to destroy insects if necessary (156) before putting in fresh supplies of grain. Grain already affected with in
sects should be put in A, diagram of an elevator : 1, endless band and
quarantine bin and treated elevator buckets for raising grain; 2, grain belt for moving grain horizontally ; 3, zigzag tor delivering grain from belt to hopper ; 4, weighing
the granary. Wherever the bin. B, detail of endless band and elevator buck
granary and rice weevil ets. C, detail of grain belt. D, detail of zigzag. (After Cobb.)
and the Angoumois grain
moth are likely to be serious pests, windows should be covered 'with screens, doors made tight, and every precaution taken to keep them from gaining entrance to the granary.
Aside from the losses occasioned by insects and vermin, the loss of weight through storage is a negligible quantity.
169. Elevators.—The elevator is an American institution which has immensely facilitated the handling of wheat and other grains, due to the fact that “threshed grain can, in large measure, be handled like water."
A country elevator. Wheat may be run directly from the threshing machine into tight wagon boxes holding fifty to 100 bushels and hauled directly to the elevator, where it is automatically dumped and elevated by power machinery, so that a pound of grain need not be lifted by hand after it starts into the threshing machine. Or it may be temporarily stored in two-bushel bags and subsequently drawn to the elevator.
The elevator company will receive, insure and store wheat for fifteen days at a fixed charge, and store indefinitely there
after for a fixed charge, depending upon the length of storage. It will also clean the wheat if desired. The owner receives a certificate of the amount of wheat stored, which he can sell whenever he desires to do so.
Country elevators are usually built of wood and have a capacity of 20,000 to 40,000 bushels; while elevators at terminal
points have been built which hold 3,000,000 bushels and are now being made of steel, concrete, or tile, thus saving largely in insurance. On the Pacific Coast, the wheat is still handled in sacks as in other countries.
1. USES AND PREPARATION FOR USE.
170. Uses.—The use of wheat as a human food is pre. historic, but by no means universal, although much more so than formerly. It is only since the application of machinery to wheat harvesting and the simultaneous development of new wheat areas, that the coarser grains have come to take a more secondary place in our dietary. The ancient Egyptians lived upon barley, sorghum seed, lupines and horse beans. Esau's mess of pottage was hulled lupines. Our New England forefathers ate “rye and Indian” (a mixture of rye and maize meal) and buckwheat principally. Wheat is almost exclusively used for the production of flour from which various forms of food are made, while its by-products serve as food for domestic animals. The value of wheat as human food does not lie so much in its superiority in sustaining life as it does in its greater palatability and the attractiveness and great variety of forms which can be made therefrom.
171. Food for Domestic Animals.—All classes of domestic animals are fond of wheat, whether fed whole or ground, wet or dry. Feeding experiments clearly indicate that the food value of wheat is slightly, if any, greater than maize, pound for pound, when fed to domestic animals. When the price permits its use under these conditions, it is a healthful and desirable food, but the best results are obtained when it does not form more than half the grain ration. When fed whole, large quantities of the grains escape mastication, but grinding has been found to increase slightly its food value. The Minnesota Station found
that when fed to pigs, ground wheat was about ten per cent more digestible than whole wheat.' The Ohio State University reports one experiment in which 399 pounds of both ground and moistened wheat produced 100 pounds of increase in pork as compared with 453 pounds of whole dry wheat. The South Dakota Station found 491 pounds of whole dry wheat and 481 pounds of ground dry wheat produced 100 pounds of increase.
172. Source, Amount and Quality of Flour. In the process of milling the aim is to reduce the endosperm to a very fine powder with as little admixture of other portions of the grain as possible. The following table gives the analysis of cleaned wheat and of three grades of flour produced therefrom by the roller process of milling. ?
(1) Patent flour: A clear white grain.
(2) Bakers' flour: Slightly yellow in color. The grain lacks distinctness, making the flour lumpy.
(3) Low grade flour: The grain is soft and the flour dark and lumpy. Particles of embryo and bran are prominent.
The low grade flour was somewhat higher in protein, considerably higher in crude fiber and much higher in phosphoric acid than the patent flour. The patent flour, which presumably formed the bulk of the product, was lower in protein and phosphoric acid than the grain. All grades of flour were lower in