EARLY DESTRUCTION OF THE TEETH. 127 



nature, which never fails to fit the organ for the 

 duty it has to perform. 



Is it at all likely that a vascular and sensitive 

 part should be destined to perform the office of 

 grinding the hard substances which oftentimes con- 

 stitute our food, and be thus exposed to the me- 

 chanical attrition which this operation necessarily 

 occasions ? Substances analogous to the structure 

 of the bone of the tooth are to be met with in 

 various parts of the animal economy, but not in 

 common bones. In the tusk of the elephant and 

 walrus ; in claws, horns, and hoofs, &c., we 

 find a striking resemblance to the bone of the 

 tooth, in their mode of formation, in structure, and 

 constitution. These substances, when once formed, 

 are insensible to pain, and therefore fitted for the 

 offices they are destined to perform. Take, for 

 instance, the horse's hoof; a considerable portion of 

 it may be pared off" with an instrument, and into 

 the remaining portion nails may be driven without 

 occasioning the slightest pain ; so that the mem- 

 brane which generates the hoofs substance is not 

 interfered with, and a sufficient thickness of hoof is 

 left to protect its membrane from external influence. 

 The same with the bone of the tooth, as before 

 stated, a gold filling may be forced into it without 

 occasioning the slightest inconvenience. 



From what has been stated — and many more 

 proofs might be adduced if time would permit, — it 

 must appear evident, I should think, to every prac- 



