BOOK V 



131 



A — Upright forked posts. B — Pole over the posts. C — Shaft. P — First cord. 

 E — Weight of first cord. F — Second cord. G — Same fixed ground. H — Head 

 of first cord. I — Mouth of tunnel. K — Third cord. L — Weight of third cord. 

 M — First side minor triangle. N — Second side minor triangle. O — Third side 

 minor triangle. P — The minor triangle. 



