NATURAL THEOLOGY. 219 



natural casket is lost, how carefully, yet how im- 

 perfectly, is it replaced by a plate of metal ! If 

 an anatomist should say, that this bony protection 

 is not confined to the brain, but is extended along 

 the course of the spine, I answer, that he adds 

 strength to the argument. If he remark, that the 

 chest also is fortified by bones, I reply, that I should 

 have alleged this instance myself, if the ribs had 

 not appeared subservient to the purpose of motion 

 as well as of defence. What distinguishes the 

 skull from every other cavity is, that the bony 

 covering completely surrounds its contents, and is 

 calculated, not for motion, but solely for defence. 

 Those hollows, likewise, and inequalities which 

 we observe in the inside of the skull, and which 

 exactly fit the folds of the brain, answer the im- 

 portant design of keeping the substance of the 

 brain steady, and of guarding it against concus- 

 sions. 



