HOUSE- t'oWERS. 113 



the bull-pinions from meshing as deeply as they should with 

 the bull-wheel. To prevent their getting loose, the large 

 set-screws are locked by means of small set-screws, which 

 bear against their threads. 



Removing the Shafts. To take out the spur-wheel shaft, 

 remove the four bolts that secure the cross-pieces to the 

 main frame, and drop them, together with the spur-pinion 

 frame, to the ground. Next remove the four bolts securing 

 the bull-pinion boxes and those securing the center boxes, 

 after which the spur-wheel shaft may be taken out without 

 disturbing the gears keyed to it. The short bull-pinion 

 shafts have trunnion-boxes at their inner ends, which permit 

 movement sufficient to allow the shafts to be removed. It 

 is necessary to remove the wood piece with slide attached, 

 which is on the rear axle. 



Reversing the Gearing. The bull-wheel may be turned 

 over, the short shafts interchanged and the spur-wheel shaft 

 reversed, (end for end), so that the teeth of all the gearing 

 may be worn on both their faces. 



Reverse Motion of Tumbling-Rods. The direction in 

 which the tumbling-rods revolve may be reversed so that 

 they turn in the same direction as that in .which the horses 

 walk, instead of turning, as usual, in the opposite direction. 

 When reverse motion is necessary for driving machinery 

 other than "Case" separators, proceed to attach the parts 

 as follows : First, bore a one and one-half inch hole in rear 

 axle, two and three-eighths inches from its top and five and 



