“Nothing more, sir, than sit on the bucket edge, with your legs inside, and hold on to the chain. When you come to it, shout, and I’ll stop.”

I did as he bid me. He went to the windlass handle, and without a moment’s hesitation began to turn. Instantly the bucket containing me swung free, and, after a little sluggish oscillation, descended slow and smooth, dropping into the bowels of the earth. It was a curious rather awful sensation, going down so into that smooth-walled shaft, with its deep-sunk eye watching for the breaking of the thread which was to precipitate me to an unthinkable death. I could not find the nerve, after one glance, to look down again. But, on the other hand, the brightness of my descent both surprised and comforted me. I had peered from above into a pit of gloom, rather appalling and fathomless to the eye; now, descending into it, under its open circular skylight all was as clear as day, so that I could see the shadows under the projecting bricks, and the little hartstongues in the crevices of mortar a vivid green.

I must have dropped already some thirty or more feet, when I saw a curious hooded bulge, so slight as to be imperceptible from above, swell from the curve of the wall; and immediately afterwards the wall itself appeared to gape beneath it like a yawning mouth. I shouted in another moment, and the bucket stopped. Right opposite me, gouged out of the wellside, was a deep niche like an oriel, forming a sort of grotto or retreat. It was quite roomy, and lined and floored with brick; and a stone ledge in it formed a seat. At the entrance an iron stanchion was let into the wall, so that one, setting the bucket gently swinging, might easily grasp that hold and land himself in the cave. A man might lie hid there indefinitely, with the aid of a confederate above, and not a soul guess the secret of his disappearance. It was as cunning a cover, I am convinced, as persecution had ever inspired.

Now, as I gazed fascinated, a certain token of some late human occupation there entered into my vision and set the brain of it reeling. I screeched out, and clung frantically to the chain. In an instant I was going upward, and in a little more the wholesome daylight came about me.

“Swing!” cried the detective, bending at the crank; and he slipped in a block that held up the machinery.

I obeyed, as well as my shaken nerves would let me; and in a little they had caught the rim of the bucket, and held it to the side while I stepped out.

“Why the devil didn’t you tell me of the blood?” I gasped, wiping my wet forehead as I stood away.

The inspector looked at me queerly.

“Truth is, sir,” he said, “I never thought. We’d had to get him out, you see; and a nice job it was. What was left of it didn’t seem to matter.”

Mr Shapter, with his eyes like grey agates, was holding my left hand in his left, his right placed sympathetically on my shoulder.