CHAP. I.] CARTILAGE — LIGAMENTS. 67 



At the ends of all bones, a yielding substance, 

 in appearance like bone itself, prevents friction, 

 and by its elasticity gives a spring to the animal's 

 steps. The ease of a horse's going mainly depends 

 upon this substance, which receives the name of 

 cartilage, and is liable in some measure to be ab- 

 sorbed or taken up into the system, or, in cases of 

 diseased joint, to become stiff and bony. Consult 

 section 23, &c on those points of information. We 

 may notice this absorption in very young animals, 

 whose bones are all substituted by cartilage, until 

 the blood furnisheth the means of forming a more 

 substantial frame, such as we have been describing; 

 and teaches the validity of some remarks I made 

 in a preceding section (15) on the kind of atten- 

 tion we ought to pay to our brood mares while the 

 foetus, or unborn animal, is being formed in the 

 womb. 



Not only between bones, and embracing every 

 joint, but at the termination of the four legs in 

 their horny feet, is this springy substance to be 

 found, the whole being liable to wear out, to con- 

 tract or to harden with age or disease ; whereby 

 all old animals appear shorter than those in the 

 vigour of youth, and horses more particularly are 

 liable to contract a stiffness of the limbs, and a 

 rigidity of the whole frame, that at its last stage 

 is termed " lock jaw." Besides this casing of 

 the joints in cartilage, the ligaments connect or tie 

 the bones together. These ligaments are seldom 

 troubled with any ailment but that of great lassitude 



