"Enough? You surely don't pretend that you will achieve your aim in an hour?" "My definite aim, no, but the aim which I am setting myself at the moment, yes . . . and even earlier. An hour? What for? To do what? Why, you'll be a good deal wiser in a few minutes!" Don Luis asked to be taken to the cellar under the library; where Essarès Bey used to keep the bags of gold until the time had come to send them off. "Was it through this ventilator that the bags were let down?" "Yes." "Is there no other outlet?" "None except the staircase leading to the library and the other ventilator." "Opening on the terrace?" "Yes." "Then that's clear. The bags used to come in by the first and go out by the second." "But . . ." "There's no but about it, captain: how else would you have it happen? You see, the mistake people always make is to go looking for difficulties where there are none." They returned to the terrace. Don Luis took up his position near the ventilator and inspected the ground immediately around. It did not take long. Four yards away, outside the windows of the library, was the basin with the statue of a child spouting a jet of water through a shell. Don Luis went up, examined the basin and, leaning forwards, reached the little statue, which he turned upon its axis from right to left. At the same time the pedestal described a quarter of a circle. "That's it," he said, drawing himself up again. "What?" "The basin will empty itself." He was right. The water sank very quickly and the bottom of the fountain appeared. Don Luis stepped into it and squatted on his haunches. The inner wall was lined with a marble mosaic composing a wide red-and-white fretwork pattern. In the middle of one of the frets was a ring, which Don Luis lifted and pulled. All that portion of the wall which formed the pattern yielded to his effort and came down, leaving an opening of about twelve inches by ten. "That's where the bags of gold went," said Don Luis. "It was the second stage. They were despatched in the same manner, on a hook sliding along a wire. Look, here is the wire, in this groove at the top." "By Jove!" cried Captain Belval. "But you've unraveled this in a masterly fashion! What about the wire? Can't we follow it?" "No, but it will serve our purpose if we know where it finishes. I say, captain, go to the end of the garden, by the wall, taking a line at right angles to the house. When you get there, cut off a branch of a tree, rather high up. Oh, I was forgetting! I shall have to go out by the lane. Have you the key of the door? Give it me, please." Patrice handed him the key and then went down to the wall beside the quay. "A little farther to the right," Don Luis instructed him. "A little more still. That's better. Now wait." He left the garden by the lane, reached the quay and called out from the other side of the wall: "Are you there, captain?" "Yes." "Fix your branch so that I can see it from here. Capital."