CAEE AND MANAGEMENT OF ANIMALS 817 



the scapula occurs, the anterior angle passing downwards 

 and forwards, the posterior upwards and backwards, until 

 the body has completed its passage over the limbs ; a final 

 movement of the scapula occurs at the moment of propul- 

 sion, the whole of the posterior angle with its attendant 

 muscle appearing to be pulled outwards from off the ribs, 

 so that the part bulges in the most marked manner. 



It is owing to these movements that we insisted in the 

 section dealing with stumbling that scapula pressure was 

 a cause not to be lost sight of, especially where small horses 

 and big saddles are employed. The scapula both for the 

 safety of horse and man must have its full range of motion 

 unimpeded ; it is hard enough for a horse to carry weight 

 on his back, but it is intolerable that he should carry it on 

 his scapulae. 



In the army, where longer and heavier saddles are used, 

 this question of scapula pressure is of the utmost moment, 

 for it is obvious, quite apart from the risk of stumbling, 

 how easily horses may tire from this cause. It can readily 

 be shown that the fore legs of the horse carry more than 

 half the weight of his body, and the weight they have to 

 carry is naturally increased by placing a man on the back. 

 The position of the rider also influences the weight carried 

 by the fore legs ; it is increased when he leans forward, 

 and decreased by leaning back. 



The influence of this on scapula pressure is very obvious, 

 but is intensified by bearing in mind that the function of 

 the fore limbs is to propel the body. The mechanical dis- 

 advantage which the features we have been considering 

 create need no further insistence. 



Where the Weight should be Carried. — We have stated, that 



the weight carried on the back is not borne by the spine 



but on the ribs. These have a flat upper surface, gradually 



increasing in width from the 8th to the 17th rib, on which 



the weight is borne. The loins, on the other hand, are 



not weight bearers, their function is concerned chiefly in 



locomotion, and if pressure be placed on them they suffer 



in consequence. There is a rolling or lateral motion in 



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