560 V THE EXTERIOR OF THE HORSE. 



indicated, the horizontal or transverse displacements of the centre of 

 gravity have not here, by reason of the irregularity of the play of the 

 members, the regular rhythm which they give in the trot, the amble, 

 and the walk. 



The interposition of the tri pedal bases (3 and 3) during the duration of the 

 diagonal base of the second period (Fig. 241, B) is not, by any means, of a nature 

 to ameliorate sensibly the lateral displacements. 



At first supported by the posterior left member, A, for example (Fig. 253), 

 the centre of gravity is displaced to E in the line CB, representing the left 



a; 



Fig. 253. 



diagonal base, and thence to 7>, upon the anterior right member. During the 

 period of projection, DA', it is carried to A', upon the posterior left member, 

 and so on. 



To recapitulate, these oscillations, very feeble in a lateral sense, do 

 not render the gait tiresome for the rider. In addition, they are so 

 much less extensive as the velocity is greater, the imprints of the right 

 feet tending then to approach, on the median line, those of the left. 



It is diiferent with the longitudinal or vertical displacements. The 

 direction of the body, primitively oblique forward and upward, now 

 becomes, at the time of the descent upon the posterior left, oblique in 

 an inverse sense, — that is to say, forward and downward at the end 

 of the contact of the anterior right. There result from this upon the 

 right diagonal biped, in galloping upon the right, alternate rotatory 

 movements which are in direct ratio with the shortness of the gait. 



When the gallop is false, the line of gravitation has a greater dis- 

 position to fall outside of the base of support, in consequence of the 

 inclination of the body towards the centre of the curve described. It 

 can be said that falls are then inevitable, if the turning be sudden 

 and the speed great. The animal preserves his equilibrium only by 

 modifying the direction of his axis in relation to that of the trail, so 

 as to be oblique instead of parallel to the latter, as it should be. If 

 the horse gallops upon the right in turning to the left, besides lessen- 

 ing his speed, he also places himself transversely to the trail and turns 

 the haunches inward in order to draw the posterior left foot to the 

 side on which the body is more liable to fall when a new stride is 

 taken. 



