NATURAL THEOLOGY. 23 



B. Are there no other bones which are united in 

 this manner? 



T. None ; it is only in the skull, that it would be 

 found useful. 



B. It is not the nature, then, of bones, as such, 

 to grow into one another in this dovetail form, but it 

 is confined to the brain case. 



T. And hence, no doubt, you considered the de- 

 sign more conspicuous, that there should be an ex- 

 ception for a single instance, and the only instance in 

 which it is required. If you know what is meant by 

 a dovetail joint, you are aware it only prevents the 

 parts which are united, from being drawn asunder. 

 The form of the joint does not secure them from 

 being lifted up, or crowded in, out of their places. 

 The mechanical contrivance for this purpose, as a 

 carpenter would say, must be a rabbeting or lapping 

 of the edges. What do the anatomists tell you as to 

 this matter in regard to the head ? 



A. That if a carpenter were to inspect this in- 

 genious work, he would be struck with observing that 

 every bone overlaps the adjoining bone at some 

 points, and at other points it is itself overlapped by 

 them ; so that it is literally impossible that any bone 

 should be driven in upon the brain without absolutely 

 breaking it, which requires a great degree of violence. 



B. One must be quite a mechanic, I perceive, 

 to understand this surprising structure. 



A. Anatomists further invite attention to another 

 particular. The teeth, which form the sutures, are 

 said not to extend through, that is, the processes or 



