138 



THE HORSE. 



mcuih ; after which, the only observable difference, until between the second 

 and third year, is in the wear of these teeth. 



The term nipper is familiar to the horseman and the farrier, and much 

 better expresses the action of these teeth than the word incisor or cutter, 

 which is adopted by anatomists. Whoever has observed a horse in the act 

 of browsing, and the twitch of the head which accompanies the separation 

 of each portion of grass, will perceive that it is nipped or torn rather than 

 cut off. 



These teeth are covered with a polished and exceedingly hard substance, 

 called the enamel ; indeed, it is so hard that it almost bids defiance to the 

 action of a file. It spreads over that portion of the teeth which appears 

 above the gum, and not only so, but as they are to be so much employed in 

 nipping the grass, and gathering up the animal's food, and in such employ- 

 ment even this hard substance must be gradually worn away, a portion of 

 it, as it passes over the upper surface of the teeth, is bent inward, and 

 sunk into the body of the teeth, and forms a little pit in them ; and the 

 inside and bottom of this being blackened by the food, constitutes the mark 

 of the teeth, by the gradual disappearance of which, in consequence of the 

 wearing down of the teeth, we are enabled for several years to judge of the 

 age of the animal. 



Dealers often talk of the filling up of the tooth. This is altogether a vulgar 

 eiTor. The mark never fills up. The peculiar cementing substance, 

 which occupies the funnel or pit made by the dipping in of the enamel, 

 never grows up, but the ridge of enamel around it is worn down, and then 

 the blackness at the bottom is rubbed off. 



The colt's nipping teeth are rounded in front, somewhat hollow towards 

 Ibe mouth, and present at first a cutting surface, with the outer edge 

 rising in a slanting direction above the inner 

 edge. This, however, soon begins to wear 

 down until both surfaces are level, and the 

 mark, which was originally long and narrow, 

 becomes shorter, and wider, and fainter. At 

 six months the four nippers are beginning to 

 wear to a level. The annexed cut will convey 

 some idea of the appearance of the teeth at 

 twelve months. The four middle teeth are evi- 

 dently level — the corner ones becoming so. The 

 mark in the two middle teeth is wide and faint j 

 in the two next teeth it is darker, and longer, 

 and narrower; and in the corner teeth it is 

 darkest, and longest, and narrowest. 



We may now speak of the back teeth or grinders. They will not guide 

 us far in ascertaining the age of the animal, for we cannot easily inspect 

 them ; but there are some interesting particulars connected with them. 

 The foal is born with two grinders in each jaw, above and below, or they 

 appear within three or four days after the birth ; and before the expiration 

 of a month they are succeeded by a third, more behind. The grinders are, 

 like the cutting teeth, covered with enamel on the sides, but not on the top, 

 though several portions of enamel enter into their substance. They have a 

 great deal more to do than the nippers, and are employed in grinding down 

 the hardest portion of the food ; nature has, therefore, made an additional 

 provision for their strength and endurance. 



This cut represents a grinder sawn across. It seems to be a most i» Teg 



