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THRASHING, or THRESHING (from " to th...

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Originally appearing in Volume V26, Page 889 of the 1911 Encyclopedia Britannica.
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THRASHING, or THRESHING (from " to thrash," O. Eng. llerscan, cf. Ger. dreschen, Du. dorschen, &c.)  , the See also:process by which the See also:grain or See also:seed of cultivated See also:plants is separated from the husk or pod which contains it . See also:Historical.—It is probable that in the earliest times the little grain that was raised was shelled by See also:hand, but as the quantity increased doubtless the grain was beaten out with a stick or the sheaf beaten upon the ground . An improvement on this, as the quantity further increased, was the practice of the See also:ancient Egyptians and Israelites of spreading out the loosened sheaves on a circular enclosure of hard ground 50 to 100 ft. in See also:diameter, and See also:driving oxen, See also:sheep or other animals See also:round and round over it so as to tread out the grain . This enclosure was placed on an elevated piece of ground so that when the See also:straw was removed the See also:wind blew away the See also:chaff and See also:left the See also:corn . This method, however, damaged See also:part of the grain, and as See also:civilization advanced it was partially superseded by the See also:thrashing sledge—the charatz of See also:Egypt and the morag of the See also:Hebrews—a heavy See also:frame mounted with three or more rollers, sometimes spiked, which revolved as it was See also:drawn over the spread out corn by two oxen . A See also:common sledge with a ridged or grooved bottom was also used . Similar methods to these were used by the Greeks and are still employed in backward countries . In See also:Italy a tapering See also:roller fastened to an upright See also:shaft in the centre of the thrashing See also:floor and pulled round from the See also:outer end by oxen is still in See also:vogue arid would seem to be a descendant of the See also:Roman tribulum or roller sledge . Doubtless the See also:flail was evolved from the See also:early method of using the stick . It seems to have been the thrashing See also:implement in See also:general use in all See also:Northern See also:European countries, and was the See also:chief means of thrashing grain as See also:late as 1860 . It was known to the See also:Japanese from the earliest times, and was probably used in See also:conjunction with the stripper, an implement fashioned very much like a large See also:comb, with the See also:teeth made of hard See also:wood and pointing upwards . The straw after being reaped was brought to this and combed through by hand, the heads being drawn off and afterwards thrashed on the thrashing floor by the flail .

At the See also:

present See also:day just such an implement, known as a " heckle," is used for combing the bolls or heads off See also:flax or for straightening the fibre in the after treatment . The flail consisted of two pieces of wood, the handstaff or helve and the beater, fastened together loosely at one end by a thong of raw hide or eelskin, which made a very durable join . The handstaff is a See also:light See also:rod of ash about 5 ft. See also:long, slightly increasing in girth at the farther end to allow for the hole for the thong to bind it to the beater . The length of the handstaff enabled the operator to stand in an upright position while working . The beater is a wooden rod about 30 in. long, made of ash, though a more compact wood such as See also:thorn is less likely to split . This also has a hole at one end for the thong to bind it to the handstaff . The shape of the beater was cylindrical, of about I} in. diameter and constructed so that the edge of the grain of the wood received the force of the See also:blow; 30 'CO 40 blows or strokes per See also:minute was the See also:average See also:speed . After the grain had been beaten out by the flail or ground out by other means the straw was carefully raked away and the corn and chaff collected to be separated by winnowing when there was a wind blowing . This consisted of tossing the mixture of corn and chaff into the See also:air so that the wind carried away the chaff while the grain See also:fell back on the thrashing floor . The best grain fell nearest while the lightest grain was carried some distance before887 falling, thus a very rough-and-ready grading of the grain was obtained . It was also performed when there was no wind by fanning while pouring the mixture from a See also:vessel . Later on a fanning or winnowing See also:mill was invented .

All ancient barns were. constructed with large doors giving on to the thrashing floor and opening in the direction of the prevailing winds so that the wind could blow right through the See also:

barn and across the thrashing floor for the purpose of winnowing the corn . The flail is still in use for See also:special purposes such as See also:flower seeds and also where the quantity grown is so small as to render it not See also:worth while to use a thrashing mill . With regard to the amount of grain thrashed in a day by the flail, a See also:fair average quantity was 8 bushels of See also:wheat, 30 bushels of oats, r6 bushels of See also:barley, 20 bushels of beans, 8 bushels of See also:rye and 20 bushels of See also:buckwheat . There seem to have been many attempts to devise some See also:form of See also:power-driven machinery for thrashing . In 1732 See also:Michael Menzies, a Scotsman, obtained a patent for a power-driven See also:machine . This was a contrivance arranged to drive a large number of flails operated by See also:water power, but though worked for a See also:time it was not particularly successful . The first See also:practical effort leading in the right direction was made by a Scottish See also:farmer named Leckie about 1758 . He invented what was described as a " rotary machine consisting of a set of See also:cross arms attached to a See also:horizontal shaft and enclosed in a cylindrical See also:case." This machine did not See also:work very well, but it demonstrated the superiority of the rotary See also:motion and pointed out the lines on which thrashing See also:machines should be constructed . The first really successful thrashing machine—the type which is embodied in See also:modern thrashers—was invented by another Scotsman named See also:Andrew Meikle in 1786 In this the loosened sheaves were fed, ears first, ,from a feeding See also:board between two fluted revolving rollers to the beating See also:cylinder . This cylinder or " See also:drum " was armed with four See also:iron-shod beaters or spars of wood parallel to its See also:axle, and these striking the ears of corn as they protruded from the rollers knocked out the grain . The drum revolved at zoo to 250 revolutions per minute and carried the loose grain and straw on to a See also:concave See also:sieve beneath another revolving drum or See also:rake with pep which rubbed the straw on to the concave and caused the grain and chaff to fall through . Another revolving rake tossed the straw out of the machine .

The straw thus passing under one peg drum and over the next was subjected to a thorough rubbing and tossing which separated the grain and chaff from it . These fell on to the floor beneath, ready for winnowing . A later development of the beater-drum was to See also:

fix iron pegs on the framework, and thus was evolved the Scottish " peg-mill," which remained the See also:standard type for nearly a See also:hundred years and is found at nearly every farmstead in See also:Scotland as a fixed machine in the barn to the present day, though in many cases unused since the See also:advent of the portable thrasher . Further, it is the type adopted in See also:America, and all " separators " in use on the See also:great wheat lands of " the See also:West " are simply modifications of the peg-mill principle . In Great See also:Britain, however, a reversion has been made to the beating or rubbing principle, where the arms of the " drum " rub the straw against an encircling concave framework and thus See also:shell the grain out, and the portable thrashing machines now taken from See also:farm to farm are all constructed on this principle . It was not till about r800 that a machine for winnowing was invented to work as part of Meikle's peg-drum thrasher, and this made a See also:complete separator or thrasher which thrashed, cleaned and delivered the grain at one operation . Still, these machines were stationary, being generally built up in homesteads and operated by water power, and the unthrashed corn had to be brought to them . See also:Port-able thrashing machines operated by See also:horse power were used to a small extent, but the work was very hard on the horses and took them away when their services were otherwise required on the farm . When See also:steam was See also:developed as a See also:motive power the portable thrashing machine became more general . When Meikle had brought together the peg-drum and concave he had solved the difficulty of See also:mechanical thrashing . The development of the machine to the efficiency of the modern thrasher was very See also:gradual, and was in the direction of greater speed to the drum and more beaters on it, and improved arrangements to ensure a clean See also:sample of grain . It is generally supposed that each part was invented and perfected singly, but in reality the early experimenters had tried to make a complete separating machine .

Phoenix-squares

In fact they covered the whole ground in theory before any See also:

main features were made practical . The Modern Thrashing Machine.—The present-day thrashing machine embodies the main features of Meikle's machine and will thrash up to 16 quarters of oats per See also:hour, depending on the See also:size of the same . There are no fluted rollers at the feed, the sheaves are fed straight to the drum ; but as the working of these high-speed drums was attended with considerable See also:risk, the Threshing Machine See also:Act 1878 now provides for some sort of guard or safety feed . In the most modern thrashing machine the See also:ordinary routine is as follows: The loosened sheaf is fed in at the feed mouth under the drum guard and passes between the drum beaters and the concave; most of the corn falls through the concave on to the corn and chaff receiving board, but some of the corn and chaff remain among the straw; as the "cavings " (the See also:short broken straw and See also:leaf) need to be separated from the straw it is given a thorough tossing up on the See also:shakers, which have an upwards and onwards peristaltic See also:action, and deliver the straw at the end of the machine . The corn, chaff and cavings fall on to a reciprocating board or " upper See also:shoe," which carries them back to the See also:middle A, Corn feed opening . 0, Grain passage . B, Thrashing drum . P, Spout . CC, Straw shakers . Q, Rotary See also:screen . D, See also:Collecting board of See also:top shoe . R, Grain passage .

EE, Caving riddle . T, Classified grain . FF, Dressing See also:

riddles . U, Rotary screen See also:brush . G, Grain spout . V, Dust spout . H, Large blower . W, Grain delivery to sacks . I, Shut off lid . X, Dust . IJ, Elevator . Z, Cavings delivery .

K, Smutter . Y, Chaff delivery or chaff collec- L, Creeper. tor may be fitted here to MM, Riddle. deliver chaff upon either N, Second blower. See also:

side of machine, as desired . of the machine, where they meet the corn that fell through the concave . The upper shoe passes the cavings, &c., over the end into a " See also:lower shoe," which thoroughly sifts the corn and chaff from the cavings . The cavings are then carried along to the outside of the machine and emerge at an opening beneath the point where the straw passes out . The corn and chaff fall through the lower shoe or caving riddle on to a receiving board (See also:Clayton & Shuttleworth, See also:Lincoln.) which takes them back to the middle of the machine, where they fall, See also:meeting with a strong blast of wind from the first See also:fan, which blows out the chaff and light See also:matter,, the small seeds and light dust being sifted out through finely perforated See also:sieves, while larger debris such as See also:thistle heads and " chobs " (broken heads) are taken off by a coarse sieve . The corn then passes into the shaker shoe, which is fitted with sieves to take off the larger seed, and thence to the elevator, which carries it to the top of the machine in a roughly dressed See also:condition . The elevator delivers the corn into the awner or " hummeller, " which is fitted with helical See also:blades to rub off the awns or beards which may still adhere to the grain . From here the grain falls on to a second See also:series of sieves, where it meets the blast of air from the second fan, which blows and sifts the light and coarse. See also:foreign matter from the grain, delivering this , debris on the first corn and chaff receiving board to undergo separation again along with that just fallen from the concave . The corn falls from the sieve of this second See also:dresser into a rotary screen where separations are made producing the clean sample and the tail corn, which are delivered at See also:separate openings below . There are modifications on the machine described—such as single fan-blast instead of See also:double, &c.--but the general principles are the same . The concave which surrounds the drum is made adjustable, so that it can be regulated according to the nature of the See also:crop to be thrashed .

An ordinary machine will thrash all usual farm crops, but great care has to be taken in adjusting the concave or the seed will be injured . See also:

Clover, however, is twice a_.—_ _ a passed through a machine of this description, to See also:free the seed from the haulm and afterwards to rub the. seed clear from the chaff, but special machines to thrash it all in one operation are made . The drum is carried on the main shaft and all other pulleys take their motion from it directly or indirectly . Sometimes the main shaft is lengthened to accommodate another See also:pulley and so drive a chaff-cutter behind and chaff up the straw as it leaves the thresher . In some districts an elevator is driven behind to stack the straw . Others use a trusser, which ties the straw into large bundles before delivering it for stacking . See also:American Machines.—In American machines the straw, cavings, &c., are caught in a blast at the See also:rear end of the machine and blown up in a light iron See also:pipe of about 18 in. diameter on to the top of the stack, and the grain is delivered loose at the side through a spout into a See also:box See also:wagon . As the See also:payment for thrashing is per See also:bushel the grain is usually passed through a self-registering weighing apparatus, so that accurate See also:account is kept of the bushels thrashed . In Great Britain payment is per See also:quarter of 8 bushels, and as the machine delivers into 4-bushel sacks this rough-and-ready measure is accepted . On American machines self-feeders are adopted, in which the sheaves are thrown on to a travelling See also:web which carries them under revolving knives to cut the bands and deliver them loose into the drum, so that while many more bushels of grain are passed per day through an American machine than is done in Great Britain, only about See also:half the men are required at the work . Thrashing Work.—The minimum number of hands required in Great Britain are: An See also:engine-See also:driver, a feeder, a sackman, and ten other men to handle the sheaves, straw, chaff, grain, &c., while half as many more may be needed where the grain has to be carted, as when the thrashing is done in the See also:field in See also:harvest time . An 8-h.p. steam engine is the usual motive power, but the development of the oil engine has provided a very satisfactory substitute .

The engine is usually of the " See also:

traction" type, so that it can move the thrashing machine or " barn work" (as it is sometimes called) and elevator from See also:place to place . The usual quantities thrashed with a " double blast See also:finishing machine," as described, in the See also:United See also:Kingdom are, with a 5 ft. wide drum, from 6o to 8o bushels per hour of wheat, and one-third to one-half more of oats and barley . Sometimes the straw is stacked loose, while sometimes it is tied up with twine by a tier exactly like that on a " See also:string binder " and then stacked up . Where all the straw is used at the farm for See also:fodder, &c., the fixed thrashing machine set up in the barn is the most convenient . The sheafed corn has to be carried to it, but, on the other hand, everything is under See also:cover, the work can be done on a wet day, and all the products of thrashing in the shape of grain, straw, cavings, chaff, &c., are kept dry . In the great corn districts, however, the portable thrasher is most convenient; it is set alongside the stack and only the grain and chaff are carried under cover, while the thrashed straw, &c., is restacked upon the spot as the work goes on . The farmer finds the See also:coal and the men and horses to See also:cart water to the engine and corn to the barn and pays the proprietor of the thrashing outfit, who finds all the other men, about the following rates: wheat, Is . Iod., oats and barley, Is . 6d. per quarter . (P .

End of Article: THRASHING, or THRESHING (from " to thrash," O. Eng. llerscan, cf. Ger. dreschen, Du. dorschen, &c.)
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want information on the bushel counters used with thrashing machines.
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