“If you can help us over any obstacles at starting, Sir Patrick, it will be a kindness to Blanche, and a kindness to me.”

“Very good.  I suppose you remember what I said to you, one morning, when we were talking of Miss Silvester at Windygates?”

“You said you had determined to let her go her own way.”

“Quite right!  On the evening of the day when I said that I received information that Miss Silvester had been traced to Glasgow.  You won’t require me to explain why I never mentioned this to you or to Blanche.  In mentioning it now, I communicate to you the only positive information, on the subject of the missing woman, which I possess.  There are two other chances of finding her (of a more speculative kind) which can only be tested by inducing two men (both equally difficult to deal with) to confess what they know.  One of those two men is—­a person named Bishopriggs, formerly waiter at the Craig Fernie inn.”

Arnold started, and changed color.  Sir Patrick (silently noticing him) stated the circumstances relating to Anne’s lost letter, and to the conclusion in his own mind which pointed to Bishopriggs as the person in possession of it.

“I have to add,” he proceeded, “that Blanche, unfortunately, found an opportunity of speaking to Bishopriggs at Swanhaven.  When she and Lady Lundie joined us at Edinburgh she showed me privately a card which had been given to her by Bishopriggs.  He had described it as the address at which he might be heard of—­and Blanche entreated me, before we started for London, to put the reference to the test.  I told her that she had committed a serious mistake in attempting to deal with Bishopriggs on her own responsibility; and I warned her of the result in which I was firmly persuaded the inquiry would end.  She declined to believe that Bishopriggs had deceived her.  I saw that she would take the matter into her own hands again unless I interfered; and I went to the place.  Exactly as I had anticipated, the person to whom the card referred me had not heard of Bishopriggs for years, and knew nothing whatever about his present movements.  Blanche had simply put him on his guard, and shown him the propriety of keeping out of the way.  If you should ever meet with him in the future—­say nothing to your wife, and communicate with me.  I decline to assist you in searching for Miss Silvester; but I have no objection to assist in recovering a stolen letter from a thief.  So much for Bishopriggs.—­Now as to the other man.”

“Who is he?”

“Your friend, Mr. Geoffrey Delamayn.”

Arnold sprang to his feet in ungovernable surprise.

“I appear to astonish you,” remarked Sir Patrick.

Arnold sat down again, and waited, in speechless suspense, to hear what was coming next.

“I have reason to know,” said Sir Patrick, “that Mr. Delamayn is thoroughly well acquainted with the nature of Miss Silvester’s present troubles.  What his actual connection is with them, and how he came into possession of his information, I have not found out.  My discovery begins and ends with the simple fact that he has the information.”