IN THE HUMAN FRAME. o7 



insertion of the bases of the muscles, and the support of 

 the ends of the ribs ; and for this fourth purpose, especial- 

 ly the former part of it, a figure, specifically suited to the 

 design, and unnecessary for the other purposes, is given to 

 the constituent bones. Whilst they are plain, and round, 

 and smooth towards the front, where any roughness or 

 projection might have wounded the adjacent viscera, they 

 run out, behind and on each side, into long processes, to 

 which processes the muscles necessary to the motions of 

 the trunk are fixed ; and fixed with such art, that, whilst 

 the vertebrae supply a basis for the muscles, the muscles 

 help to keep these bones in their position, or by their ten- 

 dons to tie them together. 



That most important, however, and general property, viz. 

 the strength of the compages, and the security against lux- 

 ation, was to be still more specially consulted ; for where 

 so many joints were concerned, and where, in every one, 

 derangement would have been fatal, it became a subject of 

 studious precaution. For this purpose, the vertebrse are 

 articulated, that is, the moveable joints between them are 

 formed, by means of those projections of their substance, 

 which we have mentioned under the name of processes ; 

 and these so lock in with, and overwrap, one another, as 

 to secure the body of the vertebrcE, not only from accident- 

 ally slipping, but even from being pushed out of its place 

 by any violence short of that which would break the bone. 

 I have often remarked and admired this structure in the 

 chine of a hare. In this, as in many instances, a plain ob- 

 server of the animal economy may spare himself the disgust 

 of being present at human dissections, and yet learn enough 

 for his information and satisfaction, by even examining the 

 bones of the animals which come upon his table. Let him 

 take, for example, into his hands, a piece of the clean-pick- 

 ed bone of a hare's back ; consisting, we will suppose, of 

 three vertebrae. He will find the middle bone of the three, 

 so implicated by means of its projections or processes, with 

 the bone on each side of it, that no pressure which he can 

 use, will force it out of its place between them. It will 

 give way neither forward, nor backward, nor on either side. 

 In whichever direction he pushes, he perceives, in the 

 form, or junction, or overlapping of the bones, an impedi- 

 ment opposed to his attempt ; a check and guard against 

 dislocation. In one part of the spine, he will find a still 

 further fortifying expedient, in the mode according to 

 F 3 



