406 



SCIENCE OF AGRICULTURE. 



Part II. 



threshing-drum, while its circular motion throws out the straw at an opening, into the 

 straw-shaker, which conveys it to the secoml shaker ; at the same time, the chaff' and 

 grain pass down through a searce, or sparred rack, into the hopper, which conveys it 

 into the fanners, by whi(;h the corn is separated from the chaff", the clean grain running 

 out at the opening, and the chaff", or any light refuse, blown out at the end by the 

 rapid motion of the fans, which are driven by a band or rope, from a sheeve placed upon 

 the axle of the threshing-drum, and passing over the sheeve, fixed upon the pivot of 

 the fans. 



2643. Meikle's threshing machine to be impelled by steam is the same arrangement of inte- 

 rior machinery with a steam engine outside of the barn connected by a shaft in the man- 

 ner of the wind and water machines. 



2644. Portable threshing machines, to be fixed in any barn, or in the open field, for 

 threshing the crops of small farms, or for other purposes of convenience, are differently 

 contrived. Excepting the hand machine, already descril>ed (2453.), all of them work by- 

 horses, and generally with one, or at most two. The most complete have a large frame 

 of separating beams into which the gudgeons of the larger wheels work,^ and which retains 

 the whole of the machinery in place. In general, there is no fanners j but sometimes a 

 winnowing machine is driven by a rope from the threshing machinery. Such machines 

 are considerably more expensive, in proportion to their power, than fixed machines; they 

 are, therefore, not mucli used, and indeed might often be profitably substituted by the 

 hand machine. 



2645. IFeir^s jwrtable tu>o horse power, threshing machine is one of the best in England. 

 The corn is threshed on Meikle's skutching principle, and is sometimes fed by fiuted 

 rollers, and sometimes introduced through a hopper directly over the drum, a mode 

 which is found not to break the straw so much as the common mode. 



2646. Lester's portable threshing machiiie received the straw without the intervention 

 of rollers, and separated the corn entirely by rubbing. It was an ingenious, but very 

 imperfect machine, and never came into use. 



2647. Forrest of ShifnaVs portable threshing machines have been employed in several 

 parts of Warwickshire, Shropshire, and adjoining counties. It combines the rubbing 

 and skutching methods, but does not perform either perfectly, Meikle's machines, in 

 fact, can alone be depended on, for completely separating the grain from the straw ; 

 though some others may render the straw less ineligible for thatch, or for gratifying the 

 present taste in litter of the London grooms. 



2648. The smut machine{Jig.350. )is the invention 

 of Hall late of Ewel, in Surrey, now of the Prairie 

 in the United States. It resembles that used for 

 dressing flour, and consists of a cylinder per- 

 forated with small holes, in the inside of which 

 are a number of brushes, which are driven round 

 with great rapidity. The wheat infected with 

 smut is put into the cylinder, by a hopper {a), 

 and the constant friction occasioned by the rapid 

 motion of the brushes (6), effectually separates the 

 smutty grain, which is driven out by the holes of 

 the cylinder. Hall finds that it requires much 

 more power to clean wheat by this machine, than 

 to dress flour. A machine on this construction, 

 might be a very useful appendage to every thresh- 

 ing machine, for the purpose of effectually clean- 

 ing all wheat intended for seed, or such wheat, 

 meant for the market, as had a great proportion of smut in it, (Stevenson's Surrey, p. 141.) 



2649. To take the awns from barley where a threshing machine is used, a notched spar 

 lined on one side, with plate iron, and just the length of the rollers, is fixed by a screw 

 bolt at each end to the inside of the cover of the drum, about the middle of it, so as the 

 edge of the notched stick is about one-eighth of an inch from the arms of the drum 

 as it goes round. Two minutes are suflficient to put it on, when its operation is wanted, 

 which is, when putting through the barJey the second time; and it is as easily taken oflT. 

 It rubs off" tlie awns completely. 



Sect, IX. Mechanical and other fixed Apparatus, f>r the Preparatlm of Food for Cattle, 

 and grinding Manure. 



2650. Tlie principal food preparing contnvances, are the steamer, boiler, roaster, 

 breaker or bruiser, and grinder. 



2651. An apparatus for steaming food for cattle, the editor of The Farmer's Magazine 

 observes, should be considered a necessary appendage to every arable and dairy farm, of 

 a moderate size. The advantage of preparing different fjorfs of roots, us well as even 



350 



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