“Mr. Francis,” he said, “I cannot talk to you.  I can say nothing.  I shall come to you at once.  I am on the point of starting.  Your news has overwhelmed me.”

He laid down the receiver.  He looked around him like a man in a nightmare.

“The taxicab is still waiting, sir,” Craig reminded him.

“That is most fortunate,” the Professor pronounced.  “I remember now that I had no change with which to pay him.  I must go back.  Look after my brother.  And, Craig, telephone at once to Mr. Sanford Quest.  Ask him to meet me at the museum in twenty minutes.  Tell him that nothing must stand in the way.  Do you hear?”

The man hesitated.  There was protest in his face.

“Mr. Sanford Quest, sir?” he muttered, as he followed his master down the hall.

“The great criminologist,” the Professor explained eagerly.  “Certainly!  Why do you hesitate?”

“I was wondering, sir,” Craig began.

The Professor waved his servant on one side.

“Do as you are told,” he ordered.  “Do as you are told, Craig.  You others—­you do not realise.  You cannot understand what this means.  Tell the taxi man to drive to the museum.  I am overcome.”

The taxicab man drove off, glad enough to have a return fare.  In about half-an-hour’s time the Professor strode up the steps of the museum and hurried into the office.  There was a little crowd of officials there whom the curator at once dismissed.  He rose slowly to his feet.  His manner was grave but bewildered.

“Professor,” he said, “we will waste no time in words.  Look here.”

He threw open the door of an anteroom behind his office.  The apartment was unfurnished except for one or two chairs.  In the middle of the uncarpeted floor was a long wooden box from which the lid had just been pried.

“Yesterday, as you know from my note,” the curator proceeded, “I was away.  I gave orders that your case should be placed here and I myself should enjoy the distinction of opening it.  An hour ago I commenced the task.  That is what I found.”

The Professor gazed blankly at the empty box.

“Nothing left except the smell,” a voice from the open doorway remarked.

They glanced around.  Quest was standing there, and behind him Lenora.  The Professor welcomed them eagerly.

“This is Mr. Quest, the great criminologist,” he explained to the curator.  “Come in, Mr. Quest.  Let me introduce you to Mr. Francis, the curator of the museum.  Ask him what questions you will.  Mr. Quest, you have the opportunity of earning the undying gratitude of a brother scientist.  If my skeleton cannot be recovered, the work of years is undone.”

Quest strolled thoughtfully around the room, glancing out of each of the windows in turn.  He kept close to the wall, and when he had finished he drew out a magnifying-glass from his pocket and made a brief examination of the box.  Then he asked a few questions of the curator, pointed out one of the windows to Lenora and whispered a few directions to her.  She at once produced what seemed to be a foot-rule from the bag which she was carrying, and hurried into the garden.