“He might be an instrument maker or a drug manufacturer; more probably the latter, as there is an extensive drug and chemical industry in Germany, and as Mr. Weiss seemed to have more use for drugs than instruments.”

“Yes, I think you are right; but we will look him up when we get home. And now we had better take a glance at the bedroom; that is, if you can remember which room it was.”

“It was on the first floor,” said I, “and the door by which I entered was just at the head of the stairs.”

We ascended the two flights, and, as we reached the landing, I halted.

“This was the door,” I said, and was about to turn the handle when Thorndyke caught me by the arm.

“One moment, Jervis,” said he. “What do you make of this?”