‘Joan! What are you doing? Are you quite mad?’ ‘Come and look down, Brion. You can see the water, miles below, like a little dim moon.’ He stood behind her, having put that force upon himself; but he sweated with apprehension. Suddenly she stooped, picked up a fragment of broken stone from the floor, and, before he could stop her, dropped it down the well. There was an interval of silence, and then a distant plop, followed once more by an exacerbated chuckling. And then, as Brion’s hair seemed to rise on his head, the girl turned on him, merrily clapping her hands. ‘Didn’t it gobble like a turkey! I know now what it is: it is the water clucking in some deep-down vent connected with the moat. I saw the bubbles rising when we crossed the tree.’ Was that, indeed, the wonderful explanation? Brion felt as if a flood of sunlight had suddenly broken into the chamber, softening and diluting its terror. ‘Joan!’ he cried amazedly, a spring of damp on his forehead. ‘Is it so, in good sooth? I believe you may be right; I believe----’ He was interrupted by his companion:-- ‘O, look at that great wheel on the wall! There is just such another in the royal Castle of Carisbrook, where once I was taken. Do you know what it is for, Brion?’ ‘Do you, Joan?’ ‘To be sure I do. It is to wind up the bucket from the well. They put a donkey inside, and he walks and turns the wheel. Only the rope is gone from this, but not the pulley. There it is, up in the roof above our heads.’ It was there, true enough. The engine of mysterious torture was resolved into a homely vehicle for an ass’s plodding. This practical little mind had dispelled at a word the last glooms of the terrific place. They went to examine the wheel together. It hung upon the wall like a huge clock which had lost its hands. Its lowest segment was sunk a foot below the pavement in an oblong hole cut to accommodate it. The sun had by now broken through the mist, and a melancholy light filtered down through the trees into the stone chamber. The great cylinder was still sound in balance and structure, and they got into it, and, working it like mice in a revolving cage, made it move. It turned slowly, groaning and sighing to be so awakened from its long slumber, but it did turn, and the easier as they continued. Presently Brion started, with a ‘Hush!’ ‘The well again?’ whispered his companion. ‘No. Methought I heard a footstep in the garden outside. Supposing old Harlock were to come in and find us?’ ‘We must not be found. If my father were to hear of our meetings!’ ‘Keep still. Do not move the wheel again for your life. Now! Step out without a sound. We must go back the way we came, and you must ride off, while I lie hid in the wood.’ They moved like cats. There was no difficulty about regaining the branch from the banked-up ground against the wall, and in a minute they were across, and had slipped into the covert of the trees on the farther side. And there they stood to part.