39 



Such provision, however, I am of opinion, has been 

 somewhat mis-stated by the majority of writers who 

 have treated of this matter. Many of these authors 

 dwell greatly upon the growth of the teeth of the 

 horse, as though this function were in constant ac- 

 tivity during the life of the animal. The arguments 

 by which their views are supported, are primarily 

 drawn from analogy rather than deduced from obser- 

 vation. Because the teeth of certain animals, espe- 

 cially those classed by naturalists as rodentia, and of 

 which the rat and rabbit are familiar types — because 

 the teeth of these creatures are known to grow, and 

 those of the elephant are also proved to increase — the 

 same is assumed of the horse. The inference is cer- 

 tainly of strength, but nevertheless it is far short of 

 proof; a similarity between the animals is not de- 

 monstrated, and a sameness cannot be shown. More- 

 over, in another direction, an evidence is attempted 

 to be made of the consequence which ensues when 

 one of the molar teeth loses its vitality ; the tooth 

 that so suffers is rapidly worn down, and the oppo- 

 sing tooth becomes of an unnatural length, projecting 

 far beyond its fellows. The increase of length in 

 such a case has been supposed to go on in the 



