THE PIAFFER 



end of the sacrum, -as the point of union of the fore 

 hand with the hind hand. Here is the junction of 

 these two parts, where they are united by the mus- 

 cles. If there were not this union, if the volitional 

 impulse came as far as the last dorsal vertebra and 

 there stopped, quadrupedal locomotion would be 

 quite impossible. 



All this is assuming that the horse is free from 

 any human interference. But if the horse's spine is 

 carrying a load, we cannot neglect the influence of 

 this weight upon the two parts of the body, which 

 are, by instinct, a unit and under the same acts of 

 will. Their point of union, in my opinion, is this 

 centrifugal region where the forces are assembled. 

 It is like the mechanical coupling which unites the 

 locomotive to the loaded cars behind it. At this 

 point all the pull of the engine is concentrated 

 against the weight opposed to it. If the cars were 

 not loaded, the coupling between the locomotive 

 and the first car would not need to be so strong. 



If a horse, when running or jumping, is watched 

 during a fall, it is easy to discover that the forward 

 part of the body gives way first. This is because 

 the hind legs do not come forward in time to act 

 their part as supports. But the hind legs, of them- 

 selves, have no power to come forward below the 

 center of gravity. The failure is in the loins, the 

 back, which have not pulled the legs forward in 

 time to lend their support, and thus to prevent the 

 fall of the whole body. 



277 



