THE DIAGONAL EFFECT 



theories are the product of philosophizing by writ- 

 ers who do more riding with a pen than with hands 

 and legs on a horse's back. 



The saddle horse is useful to mankind only by 

 virtue of its locomotion. This locomotion is the 

 consequence of impulsion; and impulsion is given 

 only by the animal's hind legs. To drive the body 

 forward, therefore, it is absolutely necessary that 

 the horse should have one or two feet on the ground. 

 A foot in the air, so long as it remains in the air, can 

 have no effect. 



But if, let us say, the right hind foot is on the 

 ground, the right hind leg may deliver its thrust 

 either to the right or to the left fore leg. In the first 

 case, the right lateral biped is set in motion, in the 

 second case, the left diagonal biped. 



In order, then, to pass from standing still, or 

 from walk or trot, to the gallop upon the right lat- 

 eral biped, the rider throws his entire weight upon 

 the right lateral biped, and at the same time, by a 

 quick inclination of the body forward to the right, 

 the rider places the horse in the position to gallop. 

 It then remains only to give the action to the whole 

 machine, the legs of the horse moving in accord 

 with the gait asked. 



This action will be given by the effect of the 

 right leg of a rider, who at the same time closes the 

 fingers of the right hand upon the right rein of the 

 curb bit or snaffle. These effects of the right leg 

 and right hand have to be executed by a quick 



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