STRUCTURES OF THE BODY. 



for we daily see instances of animals that are too heavily 

 " topped " for their legs, like the one in PI. 30. 



Men of experience know that a horse should have plenty 

 of bone in order to be able to carry weight with ease to 

 himself for long distances and at comparatively fast paces — 

 as, for example, when hunting. If we take two horses that 

 can perform about equally well in a long run with a similar 

 welter weight up, one having the " pull " in speed, the other 

 in bone and muscle, we shall usually find that the latter will 

 not feel the effects of the work so much as the former. I 

 may explain this on the reasonable supposition that the 

 weight-bearing muscles of the lighter-built horse, not being 

 so strong as those of the *' heavier " animal, will naturally 

 become more fatigued. The objection sometimes advanced 

 against thoroughbreds for hunting, that they cannot "come 

 out again " as quickly as half-bred animals, is valid only when 

 the former are lighter built than the latter ; for, if blood 

 horses of equal bone and muscle were obtained, the difference 

 would be all the other way. 



Large muscles, as we have seen, require large bones. It 

 also goes without saying that the more are bones exposed to 

 the effects of concussion, the denser and stronger should they 

 be. Consequently, we may conclude that the lighter an 

 animal's body is, in comparison to the strength of its com- 

 ponent parts and the amount of its muscular force, the 

 greater will be its powers of rapid progression. Hence we 

 find that the race-horse, like all quadrupeds of which speed is 

 the chief characteristic, has comparatively slender bones of 

 extremely dense texture, and that his muscles make up in 

 strength what they lack in substance. Owing to the law of 

 compensation, which governs the conditions of animal life, it 



