FARM MOTORS 331 



effort about 200 pounds by having a man sit astride his 

 shoulders. Experienced teamsters with light teams often 

 make use of this method of assistance in an emergency pull. 



Grip. The grip of the horse refers to the hold that he 

 secures on the surface of the road or ground. Thus, for 

 example, it is obvious that a horse without sharp shoes could 

 pull but little on ice. In like manner the horse is often 

 unable to obtain a sufficient hold on hard ground or pavement 

 to exert his full strength. 



Muscular Development. It is necessary that the horse 

 have large and powerful muscles, for these are really the 

 motors that do the work. The object of the breeder of draft 

 horses has always been directed toward the development of 

 the muscles as well as the increase in size. 



The Proper Angle of the Traces. The proper direction 

 or angle of trace is a question on which there is much differ- 

 ence of opinion. In fact there are two phases of the subject; 

 first, the angle of trace with which the horse will labor with 

 the most comfort and ease; and second, the angle of trace 

 which will move any load with the least force. The first of 

 these is the most difficult to study. If the horse can realize 

 that certain positions of the hitch, the trace, and the collar are 

 most comfortable, he cannot tell his master so. The angle of 

 trace has a very decided effect upon the maximum effort of a 

 horse. A low trace has a tendency to pull the horse into the 

 surface, thus adding to his adhesion and grip and overcoming 

 to a considerable extent the tendency to lift the forefeet from 

 the ground. It is undesirable to maintain a low trace con- 

 tinually, because the horse is compelled to carry more or less 

 of the load when less effort would be required to draw it. 

 For maximum speed it may be desirable to carry a part of 

 the horse's weight on the truck, and the racing sulky, whether 

 purposely or not, is arranged to do so. 



