"My dear doctor," said he kindly, "pray accept my apolo– gies. Viewing the matter as an abstract problem, I had forgotten how personal and painful a thing it might be to you. I assure you, however, that I never even knew that you had a brother until you handed me the watch."

"Then how in the name of all that is wonderful did you get these facts? They are absolutely correct in every particular."

"Ah, that is good luck. I could only say what was the balance of probability. I did not at all expect to be so accurate."

"But it was not mere guesswork?"

"No, no: I never guess. It is a shocking habit – destructive to the logical faculty. What seems strange to you is only so because you do not follow my train of thought or observe the small facts upon which large inferences may depend. For example, I began by stating that your brother was careless. When you observe the lower part of that watch-case you notice that it is not only dinted in two places but it is cut and marked all over from the habit of keeping other hard objects, such as coins or keys, in the same pocket. Surely it is no great feat to assume that a man who treats a fifty-guinea watch so cavalierly must be a careless man. Nei– ther is it a very farfetched inference that a man who inherits one article of such value is pretty well provided for in other respects."

I nodded to show that I followed his reasoning.

"It is very customary for pawnbrokers in England, when they take a watch, to scratch the numbers of the ticket with a pin– point upon the inside of the case.