CHAPTER XXX 

 THE PASSAGE BACKWARD 



THE passage backward follows from the piaffer, and 

 therefore presupposes a horse educated to the per- 

 fect state of assemblage and equilibrium. 



A horse at the slow piaffer which is, of course, 

 the only form of the piaffer considered by the 

 scientific equitation balances itself on the same 

 spot, all four legs flexing at the knees and hocks, but 

 without gaining ground. The center of gravity is, 

 therefore, midway of the body, and exactly under 

 the seat of the rider. Under these conditions, the 

 horse is like a large ball which rests upon a smooth 

 and level surface, with which it is in contact, only at 

 one end of a diameter. Evidently, the slightest 

 force applied at the other end of this diameter will 

 send the ball rolling in the direction of the force. 

 So, in the piaffer, a force applied alternately on the 

 two sides of the center of gravity makes the horse 

 receive its weight alternately on its two diagonal 

 bipeds. As the center of gravity shifts to the right, 

 the left diagonal biped is raised, and vice versa. 



If, then, under these conditions, the rider leans 

 forward, the horse must move forward, under the 

 operation of the same law. But if, when the horse is 

 lifting his legs in diagonal alternately upon the same 

 spot, the rider's weight is inclined backward, the al- 



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