THE HORSE IN MOTION. ' 33 



beneath the tendon, severs it with scarcely a visible external wound, 

 the muscular fibres retract the severed ends, and that ever-present, 

 inscrutable power fills in the space left by the parted extremities of the 

 tendon with new tendon, the organ is restored to proper length, and 

 the deformity is removed. If, on the other hand, one of the bony col- 

 umns of support be broken, — for example, the thigh, — the creative 

 power called nature soon sets at work to repair the damage. A seques- 

 trum, or casing, is formed around the broken extremities, consisting of 

 inelastic bony matter, to fix them in their position as a temporary expe- 

 dient, while the slower processes of the more thorough organization of 

 perfect bone is effected, and the fracture is repaired, after which the 

 sequestrum is absorbed and carried off through the circulation. While 

 this change has been taking place in the bone, it would, without surgi- 

 cal interference, in most cases be shortened by overlapping through the 

 contraction of the muscles on all sides of it. The consequence would 

 be that the same disaster would be encountered as in the last case, 

 where the muscles were supposed to be elongated from use; but another 

 law is observed. The muscle that could not elongate will shorten, and 

 the proportion between the length of the lever and the muscles which 

 act upon it is restored. 



It is said by Professor Marey that " the compaiison between ordinary 

 machines and animated motive powers will not have been made in vain 

 if it has shown that strict relations exist between the form of die organs 

 and the character of their functions ; that this correspondence is regu- 

 lated by the ordinary laws of mechanics ; so that when we see the mus- 

 cular and bony structure of an animal we may deduce from their form 

 all the characters and functions they possess." This statement, which 

 in the main appears to be true, recjuires qualification. The form of 

 many muscles is made to conform to the situation and relation of sur- 

 rounding organs. Nature, while prodigal where she can afford to be, 

 is economical where there is need of it. This is shown in numerous 

 ways, and especially in the form and arrangement of muscles. 



Beauty of form is never lost sight of in the construction of the 

 horse ; and even great sacrifices of mechanical power are made to 

 maintain graceful lines, and that general contour of form that gave 



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