37 



19. The teeth of the horse are very firmly im- 

 planted in the jaws. The fangs are of a length 

 which they who have only seen the teeth extracted 

 from the mouth of a human being would hardly 

 imagine. The length of fang of course gives the 

 teeth some security ; but this is not the only pro- 

 vision made for that end. The teeth radiate towards 

 a common centre, being widely separated at their 

 roots, but approximating at the crowns. They also 

 incline laterally from the perpendicular, so that the 

 force applied to them never acts in a direct line, or 

 is concentrated upon one particular point. 



20. The molars of the loiver jaw are the active 

 agents of mastication, for motion, during this process, 

 only takes place in that part of the head in which 

 those teeth are placed. The inferior molars are the 

 instruments that grind — the upper molars are simply 

 the surfaces upon which the food is ground. The 

 whole of the molars, however, are never simul- 

 taneously employed. The horse can chew but on 

 one side at a time, for as the inferior maxillary bone 

 is considerably narrower than the superior, if the 

 teeth on one side are brought into apposition, those of 



