“We are certainly in luck,” said he. “We ought to have very little trouble now. Number One has had the misfortune to tread in the creosote. You can see the outline of the edge of his small foot here at the side of this evil-smelling mess. The carboy has been cracked, you see, and the stuff has leaked out.”

“What then?” I asked.

“Why, we have got him, that’s all,” said he.

“I know a dog that would follow that scent to the world’s end. If a pack can track a trailed herring across a shire, how far can a specially trained hound follow so pungent a smell as this? It sounds like a sum in the rule of three. The answer should give us the—But hallo! here are the accredited representatives of the law.”

Heavy steps and the clamour of loud voices were audible from below, and the hall door shut with a loud crash.

“Before they come,” said Holmes, “just put your hand here on this poor fellow’s arm, and here on his leg. What do you feel?”

“The muscles are as hard as a board,” I answered.

“Quite so. They are in a state of extreme contraction, far exceeding the usual rigor mortis. Coupled with this distortion of the face, this Hippocratic smile, or ‘risus sardonicus,’ as the old writers called it, what conclusion would it suggest to your mind?”

“Death from some powerful vegetable alkaloid,” I answered, “some strychnine-like substance which would produce tetanus.”

“That was the idea which occurred to me the instant I saw the drawn muscles of the face. On getting into the room I at once looked for the means by which the poison had entered the system. As you saw, I discovered a thorn which had been driven or shot with no great force into the scalp. You observe that the part struck was that which would be turned towards the hole in the ceiling if the man were erect in his chair. Now examine this thorn.”

I took it up gingerly and held it in the light of the lantern. It was long, sharp, and black, with a glazed look near the point as though some gummy substance had dried upon it. The blunt end had been trimmed and rounded off with a knife.

“Is that an English thorn?” he asked.

“No, it certainly is not.”

“With all these data you should be able to draw some just inference. But here are the regulars, so the auxiliary forces may beat a retreat.”

As he spoke, the steps which had been coming nearer sounded loudly on the passage, and a very stout, portly man in a gray suit strode heavily into the room. He was red-faced, burly, and plethoric, with a pair of very small twinkling eyes which looked keenly out from between swollen and puffy pouches. He was closely followed by an inspector in uniform and by the still palpitating Thaddeus Sholto.

“Here’s a business!” he cried in a muffled, husky voice. “Here’s a pretty business! But who are all these? Why, the house seems to be as full as a rabbit-warren!”

“I think you must recollect me, Mr. Athelney Jones,” said Holmes quietly.