CHAPTER II, 



Guards Against Concussion — An Elastic Shoe- 

 Stonehenge on Tips— Etc. 



Pressure on the sole causes pain — -that is, a clegi'ee of pi'ossure which 

 is less than might be inflicted by a stone striking the sole at the junc- 

 tion of the wall and sole. This is proved by pulling off a shoe with 

 pincers, for if it does not yield readily the horse will flinch when the 

 '* purchase " is on the sole. The more central poi-tion is not so sensi- 

 tive, and the anterior part is so strongly formed that heavy blows do 

 not produce pain. In the natural, unshod foot the wear is so slight 

 at the quarters and heel that the horn of the wall and bars projects 

 enough to guard the sensitive pai'ts, and a further guai-antee against 

 injury is the elasticity of the natural sole and the spring of the frog. 

 No matter how heavy the shoe which is used, there must be violent 

 concussion when the foot strikes the ground, when the natural spring- 

 is rendered unavailable. The heavy freight-wagons of the cities, 

 which have springs under the bed sustaining the load, are found to 

 last much longer than those which ai-e without these appliances to 

 moderate the shocks of the pavements. The wheels, axles, and even 

 the tires do not wear in the same proportion, and the draft is also 

 lessened. Without springs the jar is sudden, and the impinging 

 force has nothing to break it. ^y'ithout beiug accurately a pai-allel 

 case to the foot of the horse, there is a good deal of analogy between 

 them. The living tissue, Avliile it is more sensitive, repairs itself 

 when permitted to rest ; recuperates when the cause of the injury is 

 removed. A shoe with the web so wide that it would cover the bars. 



