198 MANUAL OF MODERN FARRIERY 



corner teeth still more so, with their roots turning 

 inwards ; the semicircle formed by the roots of 

 these teeth is considerably narrower, and occupies 

 less space than that of the free portion. 



The entire length of the temporary incisors varies 

 from an inch and a quarter to an inch and three- 

 quarters ; and the permanent incisors from two inches 

 and a half to three and a quarter. Their form is not 

 the same throughout. Thus, next to the surface of 

 wear, they become flattened from front to rear, they 

 narrow towards the edge of the socket, are at first 

 oval and then rounded, and of a triangular form 

 towards the base of the root, with the extremity 

 flattened from side to side. This variation is much 

 more remarkable in the nippers and dividers than in 

 the corner teeth, which is rendered more obvious by 

 making several sections of an incisor tooth at some- 

 what about a quarter of an inch apart. We have 

 o^iven five transverse sections of the tooth of a voung" 

 horse to exhibit this: Plate v, figs. 13, 14, 15, 16, 

 and 17, have the funnel, and the sections, 16 and 17, 

 show the septum of the root of the tooth. 



The incisors of the upper jaw are stronger, 

 broader, and more developed than those of the 

 lower ; consequently the outer edge of the lower 

 corner teeth rests against the centre of the upper 

 corners, and wears them in such a manner as to 

 produce in some jaws a triangular nick, which leads 

 in a certain deofree to the determination of the ao-e 

 of a horse. This nick never appears until the horse 

 has attained its seventh year. It becomes obliterated 

 in time, but sooner in proportion as the jaw assumes 

 a horizontal direction. 



We have given representations of six teeth, show- 



