THE GENERAL STRUCTURE. 141 



I do not know how such critical deviations can, by anj- })os- 

 sible hypothesis, be accounted for without design. 



1. All the bones of the body are covered with a. jjerios- 

 teum except the teeth, where it ceases ; and an enamel of 

 ivory, wdiich saws and files vsdll hardly touch, comes into its 

 pbxje. No one can doubt of the use and propriety of this 

 difTerence — of the "analogy" being thus "interrupted" — of 

 the rule which belongs to the conformation of the bones 

 stopping where it does stop ; for, had so exquisitely sensible 

 a membrane as the periosteum invested the teeth as it invests 

 every other bone of the body, their action, necessary expos- 

 ure, and irritation, would have subjected the animal to con- 

 tinual pain. General as it is, it was not the sort of integu- 

 ment which suited the teeth : what they stood in need of 

 was a strong, hard, insensible, defensive coat ; and exactly 

 such a covering is given to them in the ivory enamel which 

 adheres to iheir surface. 



2. The scarfsldn, which clothes all the rest of the body, 

 gives way, at the extremities of the toes and fingers, to 7iaih. 

 A man has only to look at his hand, to observe with wdiat 

 nicety and precision that covering, which extends over every 

 other part, is here superseded by a different substance and a 

 different texture. Now, if either the rule had been neces- 

 sary, or the deviation from it accidental, this effect would 

 not be seen. When I speak of the rule being necessary, 1 

 mean the formation of the skin upon the surface being pro- 

 duced by a set of causes constituted without design, and act- 

 ing, as all ignorant causes must act, by a general operation. 

 Were this the case, no account could be given of the opera- 

 tion being suspended at the fingers' ends, or on the back part 

 of the fingers, and not on the fore part. On the other hand, 

 if the deviation were accidental, an error, an anomalism — 

 were it any thing else than settled by intention — we should 

 meet with nails upon other parts of the body ; they would 

 be scattered over the surface, like warts or pimples. 



3. All the great cavities of the body are enclosed by men 



