72 



diagonal relations, however, would be restored by 

 very slight movements of the points. 



§ 74. We have considered the right posterior 

 point of application as actively working in the 

 above movements of excessive action, but, since 

 there is no spring, the induced action of this point 

 by the continued working of its diagonal anterior 

 point (the leftj must be the actual course of the 

 movement, and ive may regard the head ball action in 

 the left side of the socket as the only active one 

 throughout. The secondary forcing point being 

 active only in a sufficient degree to gather up 

 in counter-action the line developed by the leading 

 one. 



In fact, the difference between halting, by equalizing 

 the four ivinding lines, as above, and locomotion, is 

 that, in thejirst, the subsequent lines are formed by 

 induction from the leading one, its action being the 

 moving principle throughout ; and as the effects are 

 distribided through the frame, the first movement is 

 continually repeated, while in the second the lines form 

 independently and separately. 



Of course the snake may halt by merely ceasing 

 the action with wliich it is moving, say just as it 

 has come to the ground with the anterior point 

 gathering, and when its shape would be that of the 



