226 NATURAL THEOLOGY. 



crease or diminish the pressure, there will be no 

 shock : the hand will be supported, or the cane 

 yield, with an easy and uninterrupted resiliency. 

 Such we conceive to be the end obtained through 

 the double curvature of the spine : that the brain 

 shall receive no shock in the sudden motions of 

 the body. 



Were we to give our attention to the processes 

 of bone which stand out from the bodies of the 

 vertebrae, we should find unexpected provisions 

 there also. It is a common remark of anatomists, 

 that the bones of the spine are secured in their 

 proper places by the relations of the surfaces in 

 contact ; the surface of the body being oblique in 

 one direction, and those of the articulating pro- 

 cesses in another — the one therefore preventing 

 the bone being dislocated forwards, and the others 

 preventing it being displaced backwards. There 

 is something more than this. The articulating 

 processes consist of two broad surfaces, which are 

 inclined in such a manner that they slide upon one 

 another — that is to say, the articulating surface 

 of the vertebra above, being itself inclined, rests 

 upon another which is also incHned. As the in- 

 tervertebral substances of the bodies yield and re- 

 coil, the articulating process of the upper vertebra 

 shifts upon the inclined surface of the process on 

 which it is seated, ascending and descending ; but 

 the impediment is greater the more the vertebra 

 descends, thus adding to the elasticity and security 

 of the whole, and preventing the abrupt shocks 



