2l8 FARM MACHINERY 



gether. The size varies from 18 X 22 inches to 44 X 66 

 inches, but the 32 X 54-inch or 36 X 58-inch are the 

 common sizes. The ratio between the width of cylinder 

 and separator varies slightly with different makes. Steam 

 traction engines are now generally used to furnish the 

 power for the larger sizes, although gasoline engines are 

 being introduced into the work. A 36 X 58-inch machine 

 requires a 15- or i6-horse-power engine, as usually rated. 

 For the smaller sizes, horse powers and portable gasoline 

 engines are generally used. The amount of grain threshed 

 a day will vary very much with the conditions of the 

 grain. There is also a wide variance in the size of ma- 

 chines, but the average-sized steam-operated outfit will 

 thresh from 500 to 1,000 bushels of wheat a day or twice 

 that number of bushels of oats. 



301. Selection. The selection of a threshing machine 

 depends upon many conditions, among which may be 

 mentioned the kind and quantity of grain to be threshed, 

 the amount of labor, the power, and the condition of the 

 bridges in the locality. There has been a gradual in- 

 crease in the size of threshing outfits for some time. 

 These large machines have an enormous capacity and re- 

 quire a large force of men to run them. However, the 

 small machine is still manufactured, and there is much 

 argument in its favor, especially so since the introduction 

 of portable gasoline engines of a size to operate it. 

 Steel is made use of to a large extent in the manufacture 

 of separators, and no doubt will prove to be a very 

 durable material when galvanized. The threshing ma- 

 chine deserves good care on the part of the owner. It 

 is an expensive machine, and much money can be saved 

 by protecting it from the weather. 



302. Bean and pea threshers differ from grain threshers 

 in having two threshing cylinders operated at different 



