He appeared to know, for he told me at once that he was Detective Gryce; a man who had grown old in solving just such baffling problems as these.

“He gave up work some time ago, I have been told,” my husband went on; “but evidently a great case still has its allurement for him.  The trail here must be a very blind one for them to call him in.  I wish we had not left so soon.  It would have been quite an experience to see him at work.”

“I doubt if you would have been given the opportunity.  I noticed that we were slightly de trop towards the last.”

“I wouldn’t have minded that; not on my own account, that is.  It might not have been pleasant for you.  However, the office is waiting.  Come, let me put you on the car.”

That night I bided his coming with an impatience I could not control.  He was late, of course, but when he did appear, I almost forgot our usual greeting in my hurry to ask him if he had seen the evening papers.

“No,” he grumbled, as he hung up his overcoat.  “Been pushed about all day.  No time for anything.”

“Then let me tell you—­”

But he would have dinner first.

However, a little later we had a comfortable chat.  Mr. Gryce had made a discovery, and the papers were full of it.  It was one which gave me a small triumph over George.  The suggestion he had laughed at was not so entirely foolish as he had been pleased to consider it.  But let me tell the story of that day, without any further reference to myself.

The opinion had become quite general with those best acquainted with the details of this affair, that the mystery was one of those abnormal ones for which no solution would ever be found, when the aged detective showed himself in the building and was taken to the room, where an Inspector of Police awaited him.  Their greeting was cordial, and the lines on the latter’s face relaxed a little as he met the still bright eye of the man upon whose instinct and judgment so much reliance had always been placed.

“This is very good of you,” he began, glancing down at the aged detective’s bundled up legs, and gently pushing a chair towards him.  “I know that it was a great deal to ask, but we’re at our wits’ end, and so I telephoned.  It’s the most inexplicable—­There! you have heard that phrase before.  But clews—­there are absolutely none.  That is, we have not been able to find any.  Perhaps you can.  At least, that is what we hope.  I’ve known you more than once to succeed where others have failed.”

The elderly man thus addressed, glanced down at his legs, now propped up on a stool which someone had brought him, and smiled, with the pathos of the old who sees the interests of a lifetime slipping gradually away.

“I am not what I was.  I can no longer get down on my hands and knees to pick up threads from the nap of a rug, or spy out a spot of blood in the crimson woof of a carpet.”