"I don't know," he resumed, "if you remember the story which the German
told to the police, and which was corroborated in every detail by the
wife or widow. Briefly it was this: Some thirty years previously,
Kershaw, then twenty years of age, and a medical student at one of the
London hospitals, had a chum named Barker, with whom he roomed,
together with another.

"The latter, so it appears, brought home one evening a very considerable
sum of money, which he had won on the turf, and the following morning he
was found murdered in his bed. Kershaw, fortunately for himself, was
able to prove a conclusive _alibi_; he had spent the night on duty at
the hospital; as for Barker, he had disappeared, that is to say, as far
as the police were concerned, but not as far as the watchful eyes of his
friend Kershaw were able to spy--at least, so the latter said. Barker
very cleverly contrived to get away out of the country, and, after
sundry vicissitudes, finally settled down at Vladivostok, in Eastern
Siberia, where, under the assumed name of Smethurst, he built up an
enormous fortune by trading in furs.

"Now, mind you, every one knows Smethurst, the Siberian millionaire.
Kershaw's story that he had once been called Barker, and had committed a
murder thirty years ago, was never proved, was it? I am merely telling
you what Kershaw said to his friend the German and to his wife on that
memorable afternoon of December the 10th.

"According to him Smethurst had made one gigantic mistake in his clever
career--he had on four occasions written to his late friend, William
Kershaw. Two of these letters had no bearing on the case, since they
were written more than twenty-five years ago, and Kershaw, moreover, had
lost them--so he said--long ago. According to him, however, the first of