"Aerial Flight" Frederick W.Lanchester 1907
 

I found this online.
Lanchester 'invented' the streamline body and a myriad of other things aerodynamic.Here's a link to the book,you can read online (nod,nod,wink,wink!)
It's a hoot!
https://archive.org/stream/aerodynam...ge/n5/mode/2up

Figure 4, Page 14
 

http://ecomodder.com/forum/attachmen...1&d=1407043150

Interestingly enough, the ratio is PI. Front angle is 34°, Rear is 18°. Max angle in tail is labeled 19.02°. Minimum Radius (yellow thing) is 1.0862.

It is amazing to think what 100 years has produced when you look at how both modern and quaint this essay seems.

P. 41.
http://ecomodder.com/forum/attachmen...1&d=1407063609

p. 369.
http://ecomodder.com/forum/attachmen...1&d=1407063633