Even that tactful reference to the tragedy was too much for Inez.  She suppressed a little convulsive sob, but did not, this time, try to flee from the room.

“You saw nothing about the den that aroused any suspicions?” pursued Kennedy.  “No bottle, no glass?  There wasn’t the odour of any gas or drug?”

Lockwood shook his head slowly, fixing his eyes on Kennedy’s face, but not looking at him.  “No,” he answered; “I have told Dr. Leslie just what I found.  If there had been anything else I’m sure I would have noticed it while I was waiting for Miss Inez to come in.”

His answers seemed perfectly frank and straight-forward.  Yet somehow I could not get over the feeling that he, as well as Inez, was not telling quite all he knew—­perhaps not about the murder, but about matters that might be related to it.

Norton evidently felt the same way.  “You saw no weapon—­a dagger?” he interrupted suddenly.

The young man faced Norton squarely.  To me it seemed as if he had been expecting the question.  “Not a thing,” he said deliberately.  “I looked about carefully, too.  Whatever weapon was used must have been taken away by the murderer,” he added.

Juanita entered again, and Inez excused herself to answer the telephone, while we stood in the living room chatting for a few minutes.

“What is this ‘curse of Mansiche’ which the Senorita has mentioned?” asked Kennedy, seeing a chance to open a new line of inquiry with Lockwood.

“Oh, I don’t know,” he returned, impatiently flicking the ashes of a cigarette which he had lighted the moment Inez left the room, as though such stories had no interest for the practical mind of an engineer.  “Some old superstition, I suppose.”

Lockwood seemed to regard Norton with a sort of aversion, if not hostility, and I fancied that Norton, on his part, neglected no opportunity to let the other know that he was watching him.

“I don’t know much about the story,” resumed Lockwood a moment later as no one said anything.  “But I do know that there is treasure in that great old Chimu mound near Truxillo.  Don Luis has the government concession to bore into the mound, too, and we are raising the capital to carry the scheme through to success.”

He had come to the end of a sentence.  Yet the inflection of his voice showed plainly that it was not the end of the idea that had been in his mind.

“If you knew where to dig,” suddenly supplied Norton, gazing keenly into the eyes of the soldier of fortune.

Lockwood did not answer, though it was evident that that had been the thought unexpressed in his remarks.

The return of the Senorita to the room seemed to break the tension.

“It was the house telephone,” she said, in a quiet voice.  “The hall-boy didn’t know whether to admit a visitor who comes with his sympathy.”  Then she turned from us to Lockwood.  “You must know him,” she said, somewhat embarrassed.  “Senor Alfonso de Moche.”