“Ah! He has left two nail-marks from his boot upon your linoleum just where the light strikes it. No, thank you, I had some supper at Waterloo, but I’ll smoke a pipe with you with pleasure.”

I handed him my pouch, and he seated himself opposite to me and smoked for some time in silence. I was well aware that nothing but business of importance would have brought him to me at such an hour, so I waited patiently until he should come round to it.

“I see that you are professionally rather busy just now,” said he, glancing very keenly across at me.

“Yes, I’ve had a busy day,” I answered. “It may seem very foolish in your eyes,” I added, “but really I don’t know how you deduced it.”

Holmes chuckled to himself.