I'm reading Galileo's Two New Sciences. But as other Scientific Book it is hard. I am having trouble in First day, where SIMPLICO asks this question(Page 7):
"But how can one make a rope one hundred cubits long out of hempen fibres which are not more than two or three cubits long, and still give it so much strength?"
Then SAGR appeals SALV to answer the question. So SALV goes on to answer it in the following way(Page 8):
[....]How are fibres, each not more than two or three cubits in length, so tightly bound together in the case of a rope one hundred cubits long that great force [violenza] is required to break it? Now tell me, Simplicio, can you not hold a hempen fibre so tightly between your fingers that I, pulling by the other end, would break it before drawing it away from you? Certainly you can. And now when the fibres of hemp are held not only at the ends, but are grasped by the surrounding medium through- throughout their entire length is it not manifestly more difficult to tear them loose from what holds them than to break them ? But in the case of the rope the very act of twisting causes the threads to bind one another in such a way that when the rope is stretched with a great force the fibres break rather than separate from each other. At the point where a rope parts the fibres are, as everyone knows, very short, nothing like a cubit long, as they would be if the parting of the rope occurred, not by the breaking of the filaments, but by their slipping one over the other.
I'm not able to understand what SALV means by example of holding fibers. And how does this answer the question of SIMP?