His eyes were on Sweetwater (a direct glance was a rare thing with Mr. Gryce), and he waited—­waited patiently for the word which did not come; then he remarked dryly: 

“We are both dull; you are tired with your day’s work and I with mine:  we will let difficult questions rest until our brains are clearer.  But”—­here he reached for the strip of dingy cloth he had cast aside, and tossing it over to Sweetwater, added with some suggestion of humor,—­“if you want a subject to dream upon to-night, there it is.  If you have no desire to dream, and want work for to-morrow, make an effort to discover from whose clothing that fell and what was its use.  It was picked up in Room B on the second floor, the one where Mrs. Taylor was detained before going downstairs.”

“Ah, something tangible at last!”

“I don’t know about that; I honestly don’t know.  But we cannot afford to let anything go by us.  Little things like that have not infrequently opened up a fresh trail which otherwise might have been missed.”

Sweetwater nodded, and laying the little strip along his palm, examined it closely.  It was made of silk, doubled, and stitched together except at the ends.  These were loose, but rough with bits of severed thread, as if the thing had been hastily cut from some article of clothing to which it had been attached by some half-dozen very clumsy stitches.

“I think I understand you, Mr. Gryce,” observed Sweetwater, rising slowly to his feet.  “But a dream may help me out; we will see.”

“I shall not leave here till ten to-morrow morning.”

“Very good, sir.  If you don’t mind, I’ll take this with me.”

“Take it, by all means.”

As Sweetwater turned to go, he was induced by the silence of his patron to cast a backward glance.  Mr. Gryce had risen to his feet and was leaning toward him with an evident desire to speak.

“My boy,” said he, “if your dreams lead you to undertake the search I have mentioned, spare nobody; I say, spare nobody.”

Then he sat down; and the memory which Sweetwater carried away with him of the old detective at the moment he uttered this final injunction was far from being a cheerful one.

XIII

“WRITE ME HIS NAME”

Refreshed by a good night’s rest and quite ready to take up his task again, Mr. Gryce sat at the same table in the early morning, awaiting the expected message from Sweetwater.  Meanwhile he studied, with a fuller attention than he had been able to give it the evening before, the memorandum which this young fellow had handed him of his day’s work.  A portion of this may be interesting to the reader.  Against the list of people registered on his chart as present in the museum at the moment of tragedy, he had inscribed such details concerning them as he could gather in the short time allotted him.

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