ble 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 the 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.

"Why, of course I do!" he wheezed. "It's Mr. Sherlock Holmes, the
theorist. Remember you! I'll never forget how you lectured us all on
causes and inferences and effects in the Bishopgate jewel case. It's
true you set us on the right track; but you'll own now that it was more
by good luck than good guidance."

"It was a piece of very simple reasoning."

"Oh, come, now, come! Never be ashamed to own up. But what is all
this? Bad business! Bad business! Stern facts here,--no room for
theories. How lucky that I happened to be out at Norwood over another
case! I was at the station when the message arrived. What d'you think
the man died of?"

"Oh, this is hardly a case for me to theorize over," said Holmes, dryly.

"No, no. Still, we can't deny that you hit the nail on the head
sometimes. Dear