“I found it rather hard to collect prints of the shoes of all of those I wished to compare.  But I have them at last.”

“And?” demanded Norton, leaning forward tensely.

“I find that there is one person whose shoe-prints are precisely the same as those we found in the Museum,” went on Kennedy, tossing over the impression he had taken.

Norton scanned the two carefully.  “I’m not a criminologist,” he said excitedly, “but to my untrained eye it does seem as though you had here a replica of the first prints, all right.”  He laid them down and looked squarely at Kennedy.  “Do you mind telling me whose feet made these prints?”

“Turn the second over.  You will see the name written on it.”

“Lockwood!” exclaimed Norton in a gasp as he read the name.  “No—­ you don’t mean it.”

“I mean nothing less,” repeated Kennedy firmly.  “I do not say what happened afterwards, but Lockwood was in the Museum, hiding in the mummy case, that night.”

Norton’s mind was evidently working rapidly.  “I wish I had your power of deduction, Kennedy,” he said, at length.  “I suppose you realize what this means?”

“What does it mean to you?” asked Kennedy, changing front.

Norton hesitated.  “Well,” he replied, “it means to me, I suppose, what it means to any one who stops to think.  If Lockwood was there, he got the dagger.  If he had the dagger—­it was he who used it!”

The inference was so strong that Craig could not deny it.  Whether it was his opinion or not was another matter.

“It fits in with other facts, too,” continued Norton.  “For instance, it was Lockwood who discovered the body of Mendoza.”

“But the elevator boy took Lockwood up himself,” objected Craig, more for the sake of promoting the discussion than to combat Norton.

“Yes—­when he ‘discovered’ the thing.  But it must have been done long before.  Who knows?  He may have entered.  The deed might have been done.  He may have left.  No one saw him come or go.  What then more likely to cover himself up than to return when he knew that his entrance would be known, and find the thing himself?”

Norton’s reasoning was clever and plausible.  Yet Kennedy scarcely nodded his head, one way or the other.

“You were acquainted with Lockwood?” he asked finally.  “I mean to say, of course, before this affair.”

“Yes, I met him in Lima just as I was starting out on my expedition.  He was preparing to come to New York.”

“What did you think of him then?”

“Oh, he was all right, I suppose.  He wasn’t the sort who would care much for an archaeologist.  He cared more for a prospector going off into the hills than he did for me.  And I—­I admit that I am impossible.  Archaeology is my life.”

Norton continued to study the prints.  “I can hardly believe my eyes,” he murmured; then he looked up suddenly.  “Does Whitney know about this—­or Lockwood?”