THE SKELETON. 57 



Lines 1, 3, 4 and the ground form a square, divid- 

 ed by lino 2 in two almost equally liigli rectangles. 

 The upper, somewhat smaller one, containing the 

 rump, the lower one the extremities. 



The depth of the rutnp, from the spinal column to 

 the breastbone, decides the dimensions of the chest. 

 This depth corresponds with the arch of the human 

 chest, and, like that arch, being far more im- 

 portant for the free expansion of the lungs, 

 than the width from shoulder to shoulder, so also 

 has the depth of the chest of the horse more 

 influence on the expansibility of the lungs, than the 

 width of the chest looked at from the front. For 

 the saddle-horse, in particular, does great depth of 

 the chest warrant a good position for the saddle. 

 The height of the upper rectangle finally decides the 

 longitudinal proportions of shoulder and armbonp, 

 hauncli and thigh bone, recognized so very important 

 for free actions. 



The lower rectangle decides the relation of the 

 length of the legs to their distance from each other. 

 We have seen how important it is that the lega 

 should cover much ground in motion. To accom- 

 plish this, they need sufficient room, and, they cau 

 only find this, if the length of the rectangle is nearly 

 twice that of its height. The more this figure re- 

 sembles a square, the less will the animal be enabled 



