127 



has such attachment only through the chest being 

 raised bj the lungs, and consequently, also only by 

 the digastrics. We should, therefore, finally, con- 

 sider the lower jaiv as the ariiflciol ground of the 

 hi-composite spine. 



§ 126. To sum up what has been said in the last 

 and several preceding sections we shall have — 



For the diagonal actions the central, the lumbar, 

 and the neck S S S. 



For the ball and socket movements connecting 

 the diagonal actions and their lines of traction for- 

 ward each to its respective " substitute ground " 

 and from these to the real ground : 



The centre of the central S between the lung lobes 

 (connecting the two C C) making the ophidian 

 spine. 



The diaphragm, between the central and lumbar 

 S S, making the lower half of the composite spine. 



The neck-root joint between the central and the 

 neck S S, making the upper haK of the composite 

 spine, the movement of which is represented by 

 the digastric muscles, between the composite spine 

 and the head. 



The head joint forms the bi-composite spine, and 

 through the shoulder-blades and lower jaw, so con- 



