The sergeant picked up a card which lay beside the dead man on the floor. The initials V. V. and under them the number 341 were rudely scrawled in ink upon it.

“What’s this?” he asked, holding it up.

Barker looked at it with curiosity. “I never noticed it before,” he said. “The murderer must have left it behind him.”

“V. V. — 341. I can make no sense of that.”

The sergeant kept turning it over in his big fingers. “What’s V. V.? Somebody’s initials, maybe. What have you got there, Dr. Wood?”

It was a good-sized hammer which had been lying on the rug in front of the fireplace — a substantial, workmanlike hammer. Cecil Barker pointed to a box of brass-headed nails upon the mantelpiece.

“Mr. Douglas was altering the pictures yesterday,” he said. “I saw him myself, standing upon that chair and fixing the big picture above it. That accounts for the hammer.”

“We’d best put it back on the rug where we found it,” said the sergeant, scratching his puzzled head in his perplexity. “It will want the best brains in the force to get to the bottom of this thing. It will be a London job before it is finished.” He raised the hand lamp and walked slowly round the the room. “Hullo!” he cried, excitedly, drawing the window curtain to one side. “What o’clock were those curtains drawn?”

“When the lamps were lit,” said the butler. “It would be shortly after four.”

“Someone had been hiding here, sure enough.” He held down the light, and the marks of muddy boots were very visible in the corner. “I’m bound to say this bears out your theory, Mr. Barker. It looks as if the man got into the house after four when the curtains were drawn and before six when the bridge was raised. He slipped into this room, because it was the first that he saw. There was no other place where he could hide, so he popped in behind this curtain. That all seems clear enough. It is likely that his main idea was to burgle the house; but Mr. Douglas chanced to come upon him, so he murdered him and escaped.”

“That’s how I read it,” said Barker. “But, I say, aren’t we wasting precious time? Couldn’t we start out and scour the country before the fellow gets away?”

The sergeant considered for a moment.

“There are no trains before six in the morning; so he can’t get away by rail. If he goes by road with his legs all dripping, it’s odds that someone will notice him. Anyhow, I can’t leave here myself until I am relieved. But I think none of you should go until we see more clearly how we all stand.”

The doctor had taken the lamp and was narrowly scrutinizing the body. “What’s this mark?” he asked. “Could this have any connection with the crime?”

The dead man’s right arm was thrust out from his dressing gown, and exposed as high as the elbow. About halfway up the forearm was a curious brown design, a triangle inside a circle, standing out in vivid relief upon the lard-coloured skin.

I did not pause to argue over this atrocious sentiment.

“I shall be back in an hour or two,” I remarked.

“All right! Good luck! But, I say, if you are crossing the river you may as well return Toby, for I don’t think it is at all likely that we shall have any use for him now.”

I took our mongrel accordingly and left him, together with a half-sovereign, at the old naturalist’s in Pinchin Lane. At Camberwell I found Miss Morstan a little weary after her night’s adventures but very eager to hear the news. Mrs. Forrester, too, was full of curiosity. I told them all that we had done, suppressing, however, the more dreadful parts of the tragedy. Thus although I spoke of Mr. Sholto’s death, I said nothing of the exact manner and method of it. With all my omissions, however, there was enough to startle and amaze them.

“It is a romance!” cried Mrs. Forrester. “An injured lady, half a million in treasure, a black cannibal, and a wooden-legged ruffian. They take the place of the conventional dragon or wicked earl.”

“And two knight-errants to the rescue,” added Miss Morstan with a bright glance at me.

“Why, Mary, your fortune depends upon the issue of this search. I don’t think that you are nearly excited enough. Just imagine what it must be to be so rich and to have the world at your feet!”

It sent a little thrill of joy to my heart to notice that she showed no sign of elation at the prospect. On the contrary, she gave a toss of her proud head, as though the matter were one in which she took small interest.

“It is for Mr. Thaddeus Sholto that I am anxious,” she said. “Nothing else is of any consequence; but I think that he has behaved most kindly and honourably throughout. It is our duty to clear him of this dreadful and unfounded charge.”

It was evening before I left Camberwell, and quite dark by the time I reached home. My companion’s book and pipe lay by his chair, but he had disappeared. I looked about in the hope of seeing a note, but there was none.

“I suppose that Mr. Sherlock Holmes has gone out,” I said to Mrs. Hudson as she came up to lower the blinds.

“No, sir. He has gone to his room, sir. Do you know, sir,” sinking her voice into an impressive whisper, “I am afraid for his health.”

“Why so, Mrs. Hudson?”

“Well, he’s that strange, sir. After you was gone he walked and he walked, up and down, and up and down, until I was weary of the sound of his footstep. Then I heard him talking to himself and muttering, and every time the bell rang out he came on the stairhead, with ‘What is that, Mrs. Hudson?’ And now he has slammed off to his room, but I can hear him walking away the same as ever. I hope he’s not going to be ill, sir. I ventured to say something to him about cooling medicine, but he turned on me, sir, with such a look that I don’t know how ever I got out of the room.”