A large part of the book is a very detailed instruction on tying complicated bell ropes.
Probably the most complete instructions to be found in print.
There are 2 Chapters (V and V1) from p9 to p35 on turk's heads which show a method where the layout of the knot is drawn life size on paper which is then fixed to the object that the knot is to be tied round.
If you are lucky enough to find a first edition you will find that it is very expensive.