“When did he come?”

“Yesterday afternoon.  He applied for the position, and, as he happened to be an acquaintance of mine, Mr. Mainwaring hired him upon my recommendation.  Now,” as he locked the door of the room they had entered, “we will open this box as quickly as possible.  I suppose there is no key to be found, and, if there were, the lock is too rusty to work.”

With the aid of a file and chisel the box was soon opened.  The satin linings were somewhat water-soaked and discolored, and the box appeared to be empty, but on opening an inner compartment there were exposed to view a pair of oddly shaped keys and a blood-stained handkerchief, the latter firmly knotted as though it had been used to bandage a wound of some kind.

“Ah!” said the detective, with peculiar emphasis, examining the handkerchief, which was of fine linen, with the initials “H.  M.” embroidered in one corner.  “Did Mr. Mainwaring carry a handkerchief of that style?”

“Yes; he carried that, or one precisely like it, the last day of his life.”

“Very good!” was the only reply, as the detective carefully folded and pocketed the article with an air that indicated that he wished to say no more about it.  “And these keys, do you recognize them?”

“They were Mr. Mainwaring’s private keys to his library and the southern hall.”

“The ones the valet said were missing?”

“The same.”

Mr. Merrick, after studying them curiously for a moment, consigned them to his pocket also, and then began a careful inspection of the interior of the box.  Scott watched him in silence, thinking meanwhile of the old document which he had found hidden away in its depths, and inwardly rejoicing that it had not been left to be discovered by the detective.  Nothing in Mr. Merrick’s manner or expression betrayed the nature of his thoughts, and, so long as he chose to remain silent, Scott refrained from questioning him.

At length he closed the box, saying, indifferently, “Well, I don’t know as there is any reason why I should detain you any longer, Mr. Scott.  We have satisfied ourselves as to the contents of the box, and you have identified the articles.  For the present, however, I would prefer that you say nothing of this.”

“Certainly, Mr. Merrick.  The discovery, whatever its import, is your secret, and I shall make no mention of it whatever.”

“I don’t know that it is of any special importance,” said the detective, carelessly, as they prepared to descend the stairs; “but it only confirms the opinion that I have had all along.”

“Don’t you think that this tends to show that the murder and robbery were connected, notwithstanding Mr. Whitney’s theories to the contrary?” Scott inquired, as they were about to separate.

“Possibly,” replied the other, gravely.  Then added, with a smile, “Mr. Whitney has his own preconceived ideas of the case and tries to adapt the circumstances to suit them, when, in reality, one must first ascertain whatever facts are available and adjust his theories accordingly.”