134 



SCIENCE OF SUCCESSFUL THRESHING 



the chains. The ring near the center of each chain is 

 merely a stop and the rods should never be hooked into it. 

 Speed of tlie Tumbling-Rods. The use of the sixteen- 

 cog pinion, which gives one hundred and one revolutions 

 of the tumbling- rods to one round of the horses, is recom- 

 mended, and will ordinarily run the cylinder of a "Case" 

 separator at the proper speed. The following table gives 

 a complete list of spur-pinions for "Case" horse-powers, 

 any of which may be obtained if desired. 



Separator Side-Gear. A separator must be fitted with 

 a side-gear, or a jack must be used, in order to be driven 

 by means of a horse-power. A speed of 750 revolutions 



