PROCESS OF TEETHING 



127 



and the tushes a few weeks, but the grinder is with difficulty 

 displaced. The three last grinders and the tushes are nevei 

 shed. 



At six years, (see Fig. 22,) Fig. 22. 



the mark on the central nip- 

 pers is worn out, There will 

 still be a difi'erence of color 

 in the centre of the tooth. 

 The cement filling up the 

 hole, made by the dipping in 

 of the enamel, will present a 

 browner hue than the other 

 part of the tooth, and it will 

 be evidently surrounded by 

 an edge of enamel, and theje 

 will even remain a little de- 

 pression in the centre, and 

 also a depression round the 

 case of enamel : but the deep hole in the centre of the teeth, with 

 the blackened surface which it presents, and the elevated edge 

 of enamel, will have disappeared. Persons not much accus- 

 tomed to horses have been puzzled here. They expected to find 

 a plain surface of a uniform color, and knew not what conclu- 

 sion to draw when there was both discoloration and irreg- 

 ularity. 



In the next incisors the mark is shorter, broader and fainter ; 

 and in the comer teeth the edges of the enamel are more regular, 

 and the surface is evidently worn. The tush has attained its full 

 growth, being nearly or quite an inch in length ; convex outward, 

 concave within ; tending to a point, and the extremity some- 

 what curved. The third grinder is fairly up ; and aU the grind- 

 ers are level. 



The horse may now be said to have a perfect mouth. AU the 

 teeth are produced, fiilly grovim, and have hitherto sustained no 

 material injury. During these important changes of the teeth, 

 the animal has sufiered less than could be supposed possible. In 

 children, the period of teething is fraught with danger. Dogs 

 are subject to convulsions, and hundreds of them die, from, the 

 irritation caused by the cutting or shedding of their teeth ; but 

 •the horse appears to feel httle inconvenience. The gums and 

 palate are occasionally somewhat hot and swollen ; but the 

 slightest scarification wiU remove this. The teeth of the horse 

 ire more necessary to him than those of the other animals are 

 to them. The child may be fed, and the dog will bolt his food ; 

 but that of the horse must be well ground down, or the nutri- 

 ment cannot be extracted from it. 



