196 MANUAL OF MODERN FARRIERY 



incisors overlapping the under, and the alveoli are 

 shallow from absorption, just as is seen in old 

 people when the chin and nose meet. 



At ten years a longitudinal groove makes its 

 appearance in the middle of the body of the corner 

 upper incisor teeth, immediately under the line of 

 the gum. This groove or longitudinal line takes 

 eleven years to come down from top to bottom, so 

 that when it reaches the bottom of these teeth the 

 horse is twenty-one years of age. To return, at 

 thirteen years the groove is a quarter way down ; at 

 fifteen to sixteen years, half-way down ; at eighteen 

 years, three-quarters ; and at twenty-one years, all the 

 way. After twenty-one years, the top of the corner 

 teeth next the gum commences to get round in shape 

 and yellow in colour, and the groove ceases. The 

 longer the round portion of the tooth above the 

 groove, the older the horse. At twenty-five or 

 twenty-six years the round portion is a quarter 

 way down, at thirty years it is round half-way 

 down. 



In consequence of the continual growing up of 

 the teeth of the bone from the side next the root, 

 and the socket not being sufficiently long, the 

 pressure of the new portion of the root gives the 

 tooth an outward inclination. Besides, these new 

 portions of the teeth being always narrower, the 

 sockets must necessarily contract, in order to secure 

 the teeth. At this time the sides of the superior 

 maxillaries become flattened, and the head assumes 

 a lengthened and pointed form, which gives to the 

 animal an appearance which is very indicative of 

 age. The horizontal direction, owing to the same 

 cause, is always a mark of advanced life, but this 

 direction is much developed in some horses, and 



