The ball had already been attached to the end of the thread, and Desmond at once lowered it down.
Presently, they heard another whistle and, hauling at it again, they found that the ball had gone, and attached to the end of the thread was a very light silken cord, which they drew in.

There was another low whistle, and all was silent.
"So far, so good," Desmond said.

"We are fairly on our way to liberty.

How long do you suppose it will take us to cut through these bars ?" "It would take us a long while to file through them all," O'Neil said, "but with a fine steel saw, I should think that a couple of nights' work should do it.

But of course that is mere guesswork, for I have not the least idea how fast even the best saw could cut through iron." "Well, there is no particular hurry, for we know that no day has been fixed yet for our trial.