ANATOMY AND PHYSIOLOGY. 421 



nerves and the heart. If design is not manifested in their 

 construction, it is difficult to see how they could be mani- 

 fested. The mechanical arrangements and operations of the 

 different parts of the system teach the same lesson. 



786. Skeleton —Spinal Column.— Take the bones of the 

 skeleton for an example. How admirably are these arranged as 

 a solid framework, around which the soft parts of the system 

 may be built up ! The vertebral column is not a single 

 straight tube, as our wisdom would probably think to be the 

 safest and best as a protection to the spinal cord within, but it 

 is made up of over thirty bones separated by an elastic sub- 

 stance, yet looked together and fastened by strong ligaments, 

 so as in fact to be stronger than a single piece, and moreover 

 it is made somewhat crooked, so that it will yield a little 

 "when jarred, and thus prevent the brain from being injured. 



787. Joints. — The joints too, how admirably fitted for the 

 manifold movements we need to make ! How securely fastened 

 together by numerous strong ligaments ! How much more 

 effectually lubricated by the synovial fluid than the most per- 

 fect engine of human construction ! Then again, how exactly 

 fitted to the parts of the body, in which they are placed, are 

 the different kinds of joints, the ball and socket, the hinge, 

 the sutures, etc. ! 



788. Muscular Arrangement —Their Mechanical Dis- 

 advantage, etc. — Contraction. — Perhaps even more striking 

 are the character, position, and mode of action of the muscles. 

 Always in pairs, except where a single one is all that is needed; 

 being antagonistic only where antagonism is wanted ; being thick 

 where great strength must be exerted, or some cavity must be 

 filled to produce symmetry of form ; being thin where wide 

 surfaces were to be covered, or a proper proportion could not 

 be secured between the different parts of the body. Then how 

 wonderful that the great mechanical disadvantage, at which 

 muscles act, which at first sight seems so obviously a defect 



