pedal left anterior support begins; the velocity falls off 

 rapidly and reaches its minimum at Epoch 14 when the 

 left fore foot is raised. The period of suspension lasts 

 from Epoch 14 to Epoch 19; it is performed at minimum 

 velocity with an appreciable increase at the end when the 

 vertical component which has raised the horse from the 

 ground is neutralized and when the body is brought back 

 toward the ground by force of gravity. 



Summing up and neglecting too delicate variations, the 

 speed is rapid in the middle of the stride (from Epoch 

 4 to Epoch 11) ; it is slow at the beginning (from i to 3) 

 and at the end (from 12 to 19). This fact can also be 

 expressed by saying that, during the period of suspension 

 and the period of rotation of legs in supporting positions, 

 the velocity of translation is from a third to a sixth slower 

 than during the formation of the diagonal support (from 

 the third to the fourth step of the stride). 



Reasoning is therefore confined by facts. 



It is evident that the velocity of the gallop would be 

 increased if it were possible materially to reduce the 

 duration of the periods during which the velocity is at 

 its minimum. This length of time is not a negligible 

 quantity, since in the example just given it is 12/19 of 

 the total duration of the stride. 



But the period of suspension is independent of the 

 will of the horse ; in each animal it is a function of his 

 own coefficient of elasticity. An elastic ball thrown with 

 a given force against ground of a given consistance will 

 rebound to a height absolutely independent of the will of 

 the thrower. It will be seen later (footnote, p. 24) 

 how this comparison may be too fixed. 



In the same way the amplitude of the oscillations of 

 the legs in their supporting positions depends upon the 

 angle at which the legs are grounded, and it is quite cer- 

 tain that at a racing pace, when the horse is doing all he 

 knows how, the legs will approach the ground at the 



15 



