vu 



saj, since some observers affirm that they have 

 discovered the tendency to a favorite side, even 

 in wild animals ; and also since it is obvious 

 that the position of the stomach, subject as this 

 organ is, to an increase in size disproportionate to 

 its pendant the hver, would favor a right hand 

 and left leg preponderance which, indeed, is so 

 general among civilized men that it has come to 

 be considered as the normal condition of the 

 frame. However this may be, we think it evident 

 that the preponderance need be but very slight, 

 and that anything beyond this measure interferes 

 with the force and free movement of both sets of 

 diagonal Hmbs. 



The fundamental actioiiy as ice have in the follow- 

 ing pages traced the theory of locomotion, is a hdi- 

 cat turning of the appuis, discharged and reduced by 

 a contrary helical turn, whose sudden discharge con- 

 stitutes a spring. The chief appui may be single, 

 as in the fish, where the ribs and fins are mere ac- 

 cessories, and the back-bone acting on the tail 

 gives propulsion to the animal. Or it may be 

 double and have independent working forces, while 

 still directed and to some extent worked by the 

 simple spine, which then becomes a neck, as in the 

 bird, where the wings and legs are attached to a 



