“Gregson is the smartest of the Scotland Yarders,” my friend remarked; “he and Lestrade are the pick of a bad lot. They are both quick and energetic, but conventional—shockingly so. They have their knives into one another, too. They are as jealous as a pair of professional beauties. There will be some fun over this case if they are both put upon the scent.”

I was amazed at the calm way in which he rippled on. “Surely there is not a moment to be lost,” I cried; “shall I go and order you a cab?”

“I’m not sure about whether I shall go. I am the most incurably lazy devil that ever stood in shoe leather—that is, when the fit is on me, for I can be spry enough at times.”

“Why, it is just such a chance as you have been longing for.”

“My dear fellow, what does it matter to me? Supposing I unravel the whole matter, you may be sure that Gregson, Lestrade, and Co. will pocket all the credit. That comes of being an unofficial personage.”

“But he begs you to help him.”

“Yes. He knows that I am his superior, and acknowledges it to me; but he would cut his tongue out before he would own it to any third person. However, we may as well go and have a look. I shall work it out on my own hook. I may have a laugh at them, if I have nothing else. Come on!”

He hustled on his overcoat, and bustled about in a way that showed that an energetic fit had superseded the apathetic one.

“Get your hat,” he said.

“You wish me to come?”

“Yes, if you have nothing better to do.” A minute later we were both in a hansom, driving furiously for the Brixton Road.

It was a foggy, cloudy morning, and a dun-coloured veil hung over the house-tops, looking like the reflection of the mud-coloured streets beneath. My companion was in the best of spirits, and prattled away about Cremona fiddles and the difference between a Stradivarius and an Amati. As for myself, I was silent, for the dull weather and the melancholy business upon which we were engaged depressed my spirits.

“You don’t seem to give much thought to the matter in hand,” I said at last, interrupting Holmes’s musical disquisition.

“No data yet,” he answered. “It is a capital mistake to theorize before you have all the evidence. It biases the judgment.”

“You will have your data soon,” I remarked, pointing with my finger; “this is the Brixton Road, and that is the house, if I am not very much mistaken.”

“So it is. Stop, driver, stop!” We were still a hundred yards or so from it, but he insisted upon our alighting, and we finished our journey upon foot.

Number 3, Lauriston Gardens wore an ill-omened and minatory look. It was one of four which stood back some little way from the street, two being occupied and two empty. The latter looked out with three tiers of vacant melancholy windows, which were blank and dreary, save that here and there a “To Let” card had developed like a cataract upon the bleared panes. A small garden sprinkled over with a scattered eruption of sickly plants separated each of these houses from the street, and was traversed by a narrow pathway, yellowish in colour, and consisting apparently of a mixture of clay and of gravel. The whole place was very sloppy from the rain which had fallen through the night. The garden was bounded by a