67 



appKcation which may be supposed to have just 

 discharged. 



By thus forcing in succession all the movements^ 

 after a full diagonal gathering, we obtain — as we 

 would by the synchronous action of both sets of 

 diagonal forces — that superimposition of torsions to 

 which reference was made in § 43, and in regard 

 to which doubts were there expressed as to the 

 capability of the snake to use this double gather- 

 ing in continuous locomotion. 



By " superimposition of tivists" we would desig- 

 nate the result of both the pairs of diagonal forces 

 being in action simultaneously. The lateral shapes- 

 of both curves will then be suppressed, although 

 the corresponding forces will stiU lie latent in the 

 spine. On the other hand, the shapes in the per- 

 pendicular plane mil remain, since they do not act 

 against each other. 



When these curvatures in the perpendicular plane 

 are fully gathered, the junction of the two C C of each 

 S, where the convexes formed by the two diagonal 

 sets of forces cut each other, will be depressed, as 

 will likewise the anterior and posterior seats of the 

 " points of application," where the courses of these 

 points cut each other. Between these the inter- 

 mediate portion of each C C will rise and there 



