VARIETIES OF WINGING 



17 



later on. It bisects the hook longitudin- 

 ally into equal and similar halves. The 

 transverse diameter CD also bisects the 

 hook, but not into equal and similar 

 halves. It represents the "lateral line." 



Now, speaking generally and ignoring 

 for the moment the importance of the 



kind of feather used, uprightness in wings 

 is secured by tying in both wings at the 

 same time on the top of the hook-shank, 

 and in such a way that each wing rests on 

 its corresponding side of the middle line, 

 and only occupies at the point where 

 it is tied in a very small portion of the 

 arc AC or AD, as the case may be 



