But, first, I would give you an insight into this man's mentality. It is a very unusual one—so much so that I think his destination is more likely to be Broadmoor than the scaffold. He has, to a high degree, the sort of mind which one associates with the mediaeval Italian nature rather than with the modern Briton. He was a miserable miser who made his wife so wretched by his niggardly ways that she was a ready prey for any adventurer. Such a one came upon the scene in the person of this chess-playing doctor. Amberley excelled at chess—one mark, Watson, of a scheming mind. Like all misers, he was a jealous man, and his jealousy became a frantic mania. Rightly or wrongly, he suspected an intrigue. He determined to have his revenge, and he planned it with diabolical cleverness. Come here!”

Holmes led us along the passage with as much certainty as if he had lived in the house and halted at the open door of the strong-room.

“Pooh! What an awful smell of paint!” cried the inspector.

“That was our first clue,” said Holmes. “You can thank Dr. Watson's observation for that, though he failed to draw the inference. It set my foot upon the trail. Why should this man at such a time be filling his house with strong odours? Obviously, to cover some other smell which he wished to conceal—some guilty smell which would suggest suspicions. Then came the idea of a room such as you see here with iron door and shutter—a hermetically sealed room. Put those two facts together, and whither do they lead? I could only determine that by examining the house myself. I was already certain that the case was serious, for I had examined the box-office chart at the Haymarket Theatre—another of Dr. Watson's bull's-eyes—and ascertained that neither B thirty nor thirty-two of the upper circle had been occupied that night. Therefore, Amberley had not been to the theatre, and his alibi fell to the ground. He made a bad slip when he allowed my astute friend to notice the number of the seat taken for his wife. The question now arose how I might be able to examine the house. I sent an agent to the most impossible village I could think of, and summoned my man to it at such an hour that he could not possibly get back. To prevent any miscarriage, Dr. Watson accompanied him. The good vicar's name I took, of course, out of my Crockford. Do I make it all clear to you?”

“It is masterly,” said the inspector in an awed voice.

“There being no fear of interruption I proceeded to burgle the house. Burglary has always been an alternative profession had I cared to adopt it, and I have little doubt that I should have come to the front. Observe what I found. You see the gas-pipe along the skirting here. Very good.