THE TEETH. 



143 



height ; externally it nas a rounded prominence, with a groove on either 

 side, and within it is evidently hollowed. Our readers need not be told that 

 from the rising of the corner nipper the animal changes its name ; the colt 

 becomes a horse, and the filly a mare. 



At five yeacs the horse's mouth is 

 almost perfect. The corner nippers 

 are quite up with the long deep mark 

 irregular on the inside ; and the other 

 nippers bearing evident tokens of in- 

 creasing wearing. The tush is mucK 

 grown ; the groves have almost, or 

 quite disappeared ; and the outer sur 

 face is regularly convex : it is still aa 

 concave within, and with the edge 

 nearly as sharp as it was six months 

 before ; the sixth molar is quite up, 

 and the third molar is wanting. This 

 last circumstance, if the general ap- 

 pearance of the animal, and particularly before, and the wearing of the 

 centre nippers, and the growth and shape of the tushes, be likewise care- 

 fully attended to, will prevent deception, if a late four-year-old be attempted 

 to be substituted for a five. The nippers may be brought up a few months 

 before their time, and the tushes a few weeks, but the grinder is with difia- 

 culty displaced. The three last grinders and the tushes are never shed. 



At six years the mark on the centre 



nippers is worn out. There will still 



\ '"^4 /^^^^^I'^i^^^^^^'^^^^^L^ ^® ^ difference of colour in the centre 



V^ \ Z^^^wi^^^^^ '^^^^^ of the tooth. The cement filling 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 



edore of enamel, and there will even 



remain a little depression in the centre, 



and also a depression round this 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 accustomed to horses have been sadly 



puzzled here. They expected to find a plain surface of an uniform colour, 



and knew not what conclusion to draw when there was both discolouration 



and irregularity. 



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

 corner 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 somewhat curved. The third grinder is fairly up, and 

 all the grinders are level. 



Now, or perhaps at the period of six months before, the horse may be 

 said to have a perfect mouth. All the teeth are produced, fully grown, 

 and have hitherto sustained no material injury. During these important 

 changes of the teeth the animal has suffered less than could be supposed 

 possible. With children, the period of teething is fraught with danger. 



