214 



posite spine ; next, the upper end of sternum, small 

 of back ; and between lung lobes for composite and 

 ophidian spines. 



§ 172. We have gone through the details of 

 equalizing the tractions of the winding lines by 

 forcing beyond their hmits those akeady formed, 

 this seeming the best way of explaining the sub- 

 ject ; but often, perhaps generally, the most prac- 

 tical method for "setting-up" is forming the alter-^ 

 nates and discharging in their "wake" the old line& 

 of the composite and ophidian spines, at the same 

 time limiting the action to these spines, which will 

 allow of equahzing each Hue after its formation. * 

 This being done, next forming successively, in the 

 same way, the alternate lines of the bicomposite 

 spine, discharging the old ones and equalizing the 

 new ones. 



No. 5. To equaHze the winding lines, the forma- 

 tion of the (right) alternate anterior line leading. As 

 has been previously remarked, the bearing of the 

 general line and the rear and front direction of the 

 leading moving points wiU be reversed from those 

 of the already given examples, because these are 

 now those of the new line forming and drawing, 



* Did the movement extend through the neck-root joint to the bicom- 

 posite spine we should have the full alternates. 



