“What became of the man?” I asked, wishing I could have had a brief interview with him.

“Lost to sight though to memory dear:  he was off like a lamplighter.  An alcoholic apple-woman picked me up and escorted me back to the hospital.  It must have been a touching spectacle,” he added, with a dry smile at the recollection.

“And I suppose they kept you there for a time to recover?”

“Yes; I went into dry dock in the O. P. room, and then old Langdale insisted on my lying down for an hour or so in case any symptoms of concussion should appear.  But I was only a trifle shaken and confused.  Still, it was a queer affair.”

“You mean the man pushing you down in that way?”

“Yes; I can’t make out how his foot got in front of mine.”

“You don’t think it was intentional, surely?” I said.

“No, of course not,” he replied, but without much conviction, as it seemed to me; and I was about to pursue the matter when Polton reappeared, and my friend abruptly changed the subject.

After dinner I recounted my conversation with Walter Hornby, watching my colleague’s face with some eagerness to see what effect this new information would produce on him.  The result was, on the whole, disappointing.  He was interested, keenly interested, but showed no symptoms of excitement.

“So John Hornby has been plunging in mines, eh?” he said, when I had finished.  “He ought to know better at his age.  Did you learn how long he had been in difficulties?”

“No.  But it can hardly have been quite sudden and unforeseen.”

“I should think not,” Thorndyke agreed.  “A sudden slump often proves disastrous to the regular Stock Exchange gambler who is paying differences on large quantities of unpaid-for stock.  But it looks as if Hornby had actually bought and paid for these mines, treating them as investments rather than speculations, in which case the depreciation would not have affected him in the same way.  It would be interesting to know for certain.”

“It might have a considerable bearing on the present case, might it not?”

“Undoubtedly,” said Thorndyke.  “It might bear on the case in more ways than one.  But you have some special point in your mind, I think.”

“Yes.  I was thinking that if these embarrassments had been growing up gradually for some time, they might have already assumed an acute form at the time of the robbery.”

“That is well considered,” said my colleague.  “But what is the special bearing on the case supposing it was so?”

“On the supposition,” I replied, “that Mr. Hornby was in actual pecuniary difficulties at the date of the robbery, it seems to me possible to construct a hypothesis as to the identity of the robber.”

“I should like to hear that hypothesis stated,” said Thorndyke, rousing himself and regarding me with lively interest.

“It is a highly improbable one,” I began with some natural shyness at the idea of airing my wits before this master of inductive method; “in fact, it is almost fantastic.”