"Yours truly,
"Walter Bent."
At first I only glanced hurriedly down the lines, experiencing an almost astonished satisfaction at the extent to which I had—to use a term current, I believe, in financial circles—"roped in" the great scientist. With a second and closer reading, an element of indefinable doubt crept into my mind. It is true that in the course of the article I had found it necessary to refer to myself (though strictly in the third person), and even to touch lightly on my qualifications, but I could recall no expression indicating that I laboured under any difficulties whatever; it is equally true that I had written of Sir Walter himself in terms of graceful appreciation, but with no suggestion that called for his allusion to definite proof. I was beginning the letter for a third time when my nephew, who had been in the room all the time, I suppose, although I had not noticed him before, interrupted me.
"Excuse me, uncle," he said, "but as you seem puzzled, perhaps that letter is not for you."
I laid it down on the table and looked at him in speech-
