HORSE-POWERS 137 



slotted holes. These allow adjustment of the pinion so 

 that it may be made to mesh properly with the spur-wheel. 

 These gears, when properly adjusted, should not have more 

 than one-sixteenth of an inch clearance under the points 

 of the teeth, and pinion shaft should be parallel with the 

 spur-wheel shaft. 



Caution Concerning the Bull-Pinion Boxes. The bull- 

 pinion boxes, 45 W and 45^W or 8i%W and 8i>^W, 

 have flanges which hook over the outside of the main 

 frame, thus preventing them from crowding toward the 

 center. When these boxes have been removed, care must 

 be taken in replacing them to insure these flanges hooking 

 over the outside of the frame, for if they be placed too far 

 toward the center of the power, these flanges may come in 

 contact with the box seat and prevent 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, "'hich 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, 



