528 AET OF SHOEING. 



hind limbs ; in this classification, the other bones special to the 

 knee and hock are not taken account of 



The 'function of the bones of the last order described is 

 necessary to be understood, inasmuch as it differs from that 

 of the sustainers, and it is only by understanding these in 

 detail that anything can be fully estimated, either of normal 

 action, or of disordered conditions. 



The bones which are all placed behind the axis of bearing, 

 constitute the medium by which muscular energy is made 

 to act with great force, but these have little more to do 

 in sustaining the superincumbent weight, than have . the 

 trochanters of the femur, the use of which is obvious to 

 all anatomists, viz., that they form projections for uplifting 

 power; taking another example, we may adduce the patella, 

 the great and essential offices of which are most distinct 

 from that of sustaining the superincumbent weight; and 

 just in the same way may the navicular and sessamoid bones 

 be viewed; whilst the splint bones, and those projecting pos- 

 teriorly of the knee and hock, are so fixed and acted on directly 

 by muscular power, that they constitute additional parts of 

 the shafts, a main function of which is their uplifting action. 



The os pedis, or coffin bone, is peculiar in the horse, both in 

 its structure and economy; there is a close analogy between 

 that bone in the horse, and the double formation of the 

 same in the ox, but the resemblance is only partial, each ani- 

 mal being perfect for the useS and situations for which it 

 was designed ; the cloven-footed animal moves with astonish- 

 ing security over granite rocks, where the horse is less 

 adapted to go ; this fact is illustrated in the different kinds of 

 goat, deer, and in a lesser degree in the ox. All cloven-footed 

 animals are endowed with remarkable security of foot-hold, 

 but want the elasticity to carry weight, and the graceful 

 movement of the horse, with his ample security over hill and 



