The constable’s features broadened into a grin. “I’ve seen many a drunk chap in my time,” he said, “but never anyone so cryin’ drunk as that cove. He was at the gate when I came out, a-leanin’ up ag’in the railings, and a-singin’ at the pitch o’ his lungs about Columbine’s New-fangled Banner, or some such stuff. He couldn’t stand, far less help.”

“What sort of a man was he?” asked Sherlock Holmes.

John Rance appeared to be somewhat irritated at this digression. “He was an uncommon drunk sort o’ man,” he said. “He’d ha’ found hisself in the station if we hadn’t been so took up.”

“His face - his dress - didn’t you notice them?” Holmes broke in impatiently.

“I should think I did notice them, seeing that I had to prop him up - me and Murcher between us. He was a long chap, with a red face, the lower part muffled round- -”

“That will do,” cried Holmes. “What became of him?”

“We’d enough to do without lookin’ after him,” the policeman said, in an aggrieved voice. “I’ll wager he found his way home all right.”

“How was he dressed?”

“A brown overcoat.”

“Had he a whip in his hand?”

“A whip - no.”

“He must have left it behind,” muttered my companion. “You didn’t happen to see or hear a cab after that?”

“No.”

“There’s a half-sovereign for you,” my companion said, standing up and taking his hat. “I am afraid, Rance, that you will never rise in the force. That head of yours should be for use as well as ornament. You might have gained your sergeant’s stripes last night. The man whom you held in your hands is the man who holds the clue of this mystery, and whom we are seeking. There is no use of arguing about it now; I tell you that it is so. Come along, Doctor.”

We started off for the cab together, leaving our informant incredulous, but obviously uncomfortable.

“The blundering fool!” Holmes said, bitterly, as we drove back to our lodgings. “Just to think of his having such an incomparable bit of good luck, and not taking advantage of it.”

“I am rather in the dark still. It is true that the description of this man tallies with your idea of the second party in this mystery. But why should he come back to the house after leaving it? That is not the way of criminals.”

“The ring, man, the ring: that was what he came back for. If we have no other way of catching him, we can always bait our line with the ring. I shall have him, Doctor - I’ll lay you two to one that I have him. I must thank you for it all. I might not have gone but for you, and so have missed the finest study I ever came across: a study in scarlet, eh? Why shouldn’t we use a little art jargon. There’s the scarlet thread of murder running through the colourless skein of life, and our duty is to unravel it, and isolate it, and expose every inch of it. And now for lunch, and then for Norman Neruda. Her attack and her bowing are splendid. What’s that little thing of Chopin’s she plays so magnificently: Tra-la-la-lira-lira-lay.”

Leaning back in the cab, this amateur bloodhound carolled away like a lark while I meditated upon the many-sidedness of the human mind.