THRASHER 



5800 



THREAD 



cia became a Roman province. Its most im- 

 portant towns were Abdera, the birthplace of 

 Democritus; Sestos, on the Hellespont, cele- 

 brated in the story of Hero and Leander; and 

 Byzantium, on the peninsula now occupied by 

 Constantinople. Greece is generally supposed 

 to owe the foundation of its music, mythology 

 and philosophy to Thrace. 



THRASH 'ER. See BROWN THRASHER. 



THRASHING MACHINE (also spelled 

 THRESHING MACHINE). The thrashing engine 

 ranks next in importance to the harvester 

 among agricultural machines, and since the 

 middle of the nineteenth century there has been 

 about as much improvement in the one as in 

 the other. The modern thrashing machine is a 

 combination of three machines the thrasher, 

 the winnowing machine and the stacker which 

 are united in a single frame that is mounted on 

 wheels so that the machine can be moved from 

 field to field. The thrasher consists of an iron 

 cylinder called the beater, to which vertical 

 teeth are attached in rows, and a concave, 

 which is a section of a similar cylinder with the 

 teeth on its inner surface. These are so ad- 

 justed that they nearly touch the teeth of the 

 cylinder. A feed board or grain conveyor re- 

 ceives the grain before it passes to the cylinder, 

 and just back and a little below the cylinder is 

 a grate, consisting of parallel steel slots against 

 which the thrashed straw is forcefully thrown. 

 Most of the grain falls through the slots to the 

 grain conveyor, while the straw carrier, which 

 has a vibratory motion for shaking out the re- 

 maining grain, conveys the straw to the stacker. 



The grain conveyor carries the grain to the 

 winnowing machine, where the grain is sepa- 

 rated from the chaff and made to pass through 

 a series of screens of different meshes to remove 

 the inferior kernels and the seeds of weeds. 

 The cleaned grain falls into a cylindrical box 

 under the screens, called the augur, from which 

 an elevator takes it to the weighing and meas- 

 uring device. The grain may be placed in 

 sacks or loaded into wagons as it comes from 

 the machine. The stacker consists of a long 

 tube connected with a blowing machine, which 

 forces the straw up to the stack. 



A modern thrashing machine requires a 

 twelve or fifteen horse-power engine for its 

 successful operation, and it will thrash from 

 1,200 to 1,500 bushels of wheat in a day. A 

 machine with a grain conveyor cuts the bands 

 and separates the grain in the bundles ready for 

 the beater, so that bundles may be thrown 

 directly from the stack or loaded upon it. The 



grain thrashed and cleaned pours from the ele- 

 vator in a stream which fills bushel measures as 

 fast as a man can empty them into a wagon. 



Formerly steam engines were employed for 

 operating thrashers, and a type that burned 

 straw was very common in the great wheat- 

 growing regions, but these engines are being re- 

 placed by internal-combustion engines. 



In regions where the grain can dry on the 

 stalk the combined harvester and thrasher, de- 

 scribed in the article REAPING MACHINE, is used. 



The most recent type of machine is that in- 

 vented by Curtis C. Baldwin of Kansas. The 

 machine goes to the grain instead of having the 

 grain brought to it. As it moves through a field 

 of standing grain, it blows a blast of air from 

 revolving fans against the stems, forcing them 

 against a toothed cylinder that beats out the 

 grain and deposits it in a trough. Augurs ele- 

 vate the grain to a second toothed cylinder, 

 which beats it anew. The chaff is blown out, 

 and the clean grain falls into sacks. Four 

 horses pull the machine across the field, and a 

 small gasoline engine operates the blasts and 

 the beating devices. Two men are all that are 

 required to operate it. The straw is left stand- 

 ing in the field, to be plowed under as fertilizer. 



History. We read in the Bible that the He- 

 brews thrashed their grain by spreading it on 

 hard ground or a floor and driving oxen over it. 

 The Egyptians used a sort of sledge which was 

 hauled over the grain, and the Greeks and Ro- 

 mans employed methods similar to those of 

 older nations. The flail (which see) came into 

 use in Northern Europe in the Middle Ages, 

 and it was in general use among the early set- 

 tlers of America until it was replaced by the 

 thrashing machine. The thrasher, after which 

 all later machines have been patterned, was in- 

 vented by Andrew Meikle, a Scotch mechanic, 

 in 1786. W.F.R. 



Consult Conner's Science of Threshing; David- 

 son and Chase's Farm Machinery and Farm 

 Motors. 



THREAD, firmly-twisted fibers of cotton, 

 flax or silk. Because of its cheapness cotton is 

 more extensively used in the manufacture of 

 thread than either silk or flax, and the long- 

 fiber sea-island variety is the most valuable for 

 the purpose. The supremacy of cotton in this 

 field dates from 1794, when Samuel Slater be- 

 gan the manufacture of cotton thread in Paw- 

 tucket, R. I. 



The process is very complicated. After the 

 fibers are cleaned they are combed in carding 

 machines until the tangles are smoothed out; 



