FARM MACHINERY 275 



furnished with interchangeable shredder knives for prepar- 

 ing dry fodder. 



Elevating Mechanism. The pneumatic elevator, or 

 blower, offers many advantages over the carrier elevator. 

 It is easily adjusted to a silo of any height and is less likely 

 than others to cause trouble. It requires considerably more 

 power; in fact, without any definite information, it would 

 seem that in many cases the blower requires at least one-half 

 of the power supplied. If the engine is large and there is a 

 surplus of power, the convenience of the blower may overbal- 

 ance its extravagance in consuming power. The blower is 

 more durable than the long chain elevators. It must be 

 driven above a certain speed or sufficient blast will not be 

 developed to elevate the silage. The blower pipe should 

 always be set nearly vertical, or the silage will settle to one 

 side of the pipe and not be elevated. 



Self-feed. The advantages of the self-feed are so great 

 that every machine should be provided with one. This self- 

 feed should be capable of having its speed adjusted to furnish 

 a desired length of cut. The length of cut may be varied in 

 some machines from \i inch to \y 2 inches. Three-fourths 

 of an inch is the popular length of cut among many feeders. 

 In addition, the force feed should have a safety lever for 

 instantly reversing the feed rolls and carrier in order to pre- 

 vent accidents. 



Mounting. Ensilage cutters may be mounted either on 

 skids or on trucks. The trucks add much to their conveni- 

 ence, and should always be provided for the larger machines. 

 In selecting the machine it is well to notice if the truck is of 

 good substantial construction. There has been a tendency 

 to use very small wheels, often of cast-iron, which are very 

 liable to break. 



