“I was waiting for my master,” Craig explained.

“Why not downstairs?” Lenora asked suspiciously.  “You did not come up with him.”

“I am driving the Professor in his automobile,” Craig explained.  “It occurred to me that if he were going to be long here, I should have time to go and order another tire.  It is of no consequence, though.  I will go down and wait in the car.”

Lenora stood at the top of the stairs and watched him disappear.  Then she went thoughtfully back to her work.  The Professor and Quest were talking at the farther end of the room.

“I was in hopes, in great hopes,” the Professor admitted, “that you might have heard something.  I promised to call at Mrs. Rheinholdt’s this afternoon.”

Quest shook his head.

“There is nothing to report at present, Mr. Ashleigh,” he announced.

“Dear me,” the Professor murmured, “this is very disappointing.  Is there no clue, Mr. Quest—­no clue at all?”

“Not the ghost of one,” Quest acknowledged.  “I am as far from solving the mystery of the disappearance of your skeleton and Mrs. Rheinholdt’s necklace, as I have ever been.”

The Professor failed entirely to conceal his disappointment.  His tone, in fact, was almost peevish.

“I should have expected this from the regular officials of the law, Mr. Quest,” he admitted, “but I must say that in your hands I had hoped—­but there, there!  Excuse me!  I am an old man, Mr. Quest.  I am getting a little irritable.  Disappointments affect me quickly.  I must be patient.  I will be patient.”

“There are certain evidences,” Quest remarked, with his eyes upon the black box, “which seem to point to a new arrival in the criminal world of New York.  More than that I cannot tell you.  I will simply ask you to believe that I am doing my best.”

“And with that, Mr. Quest, I will be content,” the Professor promised.  “I will now pay my promised call upon Mrs. Rheinholdt.  I shall convey to her your assurance that everything that is possible is being done.  Good morning, young ladies,” he concluded.  “Good morning, Mr. Quest.”

He took a courteous leave of them all and departed.  Lenora crossed the room to where Quest was seated at the table.

“Mr. Quest,” she asked, “do you believe in inspiration?”

“I attribute a large amount of my success,” Quest replied, “to my profound belief in it.”

“Then let me tell you,” Lenora continued, “that I have one and a very strong one.  Do you know that when I went to the door a few minutes ago, the Professor’s servant, Craig, was there, listening?”

“Craig?” Quest repeated.  “Let me see, that was the man who was at the Rheinholdts’ house the night of the robbery, and who might have left through the conservatory.”

“He did leave by it,” Lenora declared.  “He is in a state of panic at the present moment.  What else do you suppose he was out there listening for?”