24 EXTERNAL CONFORMATION OF THE HORSE. 



they descend to the feet ; the arm should be muscular and 

 large ; when small, it generally denotes want of strength ; the 

 knee large and flat, and the shank muscular and firm, and by 

 no means fleshy. The thighs of the horse should be exceed- 

 ingly strong and muscular ; the stifle should be of considerable 

 length, as that denotes speed. The hock is the most material 

 joint of the animal, and should be broad and wide ; it is 

 subject to many diseases, and ought to be well looked to. 

 The feet also require attention, and are more frequently mis- 

 shapen ; they should not be too upright, which tends to open 

 the heel, and thus the feet become faulty and diseased ; the 

 horn should be of considerable size, otherwise the foot is 

 easily hurt, and rendered unhealthy. By reference to plate 

 No. 1, the reader may become acquainted with the bony 

 structure of this noble animal. 



On the Teeth. — A horse has forty teeth when he has 

 completed his full number; a mare usually only thirty-six. 

 The horse has, during life, two sets of teeth — a temporary 

 and a permanent set. The first appears shortly after birth ; 

 the others appear gradually, as the temporary set fall out; 

 and the change is completed about the fifth year. These 

 two sets of teeth appear at an interval of a few years be- 

 tween them ; yet the rudiments of both are formed nearly at 

 the same period. It is essentially necessary that there should 

 be two sets of teeth ; for, as they grow but slowly in propor- 

 tion to the jaws, had there been but one set, the disproportion 

 in growth between the teeth and jaws must have separated 

 and made them wide apart as the jaws increased. The 

 manner in which the temporary teeth are removed is very 

 curious ; — it is occasioned by the pressure of the permanent 

 teeth upon the roots of the former; this causes a gradual 

 absorption of the roots, so that, after a time, having no sup- 

 port, they fall out. The teeth are covered with a hard sub- 

 stance called enamel ; this enamel surrounds the tooth, and 

 is indented or sunk into it, forming a pit, or hollow, which 

 preserves the body of the tooth from being injured. In pro- 

 cess of time, however, the enamel is worn down below the 



