“It could not be Mr. Lockwood?” demanded Craig.

“Who sent it?” he asked, looking up.

“No—­whom it warns against.”

De Moche had known what Kennedy meant, but had preferred to postpone the answer.  It was native never to come to the point unless he was forced to do so.  He met our eyes squarely.  He had not the penetrating power that his mother possessed, yet his was a sharp faculty of observation.

“Mr. Lockwood is very friendly with her,” he admitted, then seemed to think something else necessary to round out the idea.  “Mr. Kennedy, I might have told her the same myself.  Senorita Mendoza has been a very dear friend—­for a long time.”

I had been so used to having him evasive that now I did not exactly know what to make of such a burst of confidence.  It was susceptible of at least two interpretations.  Was he implying that it was sent to cast suspicion on him, because he felt that way himself or because he himself was her friend?

“There have been other warnings,” pursued Kennedy, “both to myself and Mr. Jameson, as well as Professor Norton and Dr. Leslie.  Surely you must have some idea of the source.”

De Moche shook his head.  “None that I can think of,” he replied.  “Have you asked my mother?”

“Not yet,” admitted Kennedy.

De Moche glanced at his watch.  “I have a lecture at this hour,” he remarked, evidently glad of an excuse to terminate the interview.

As he left, Kennedy accompanied him to the door, careful himself to step over the mat.

“Hello, what’s new?” we heard a voice in the hall.

It was Lockwood, who had come up from downtown.  Catching sight of de Moche, however, he stopped short.  The two young men met face to face.  Between them passed a glance of unconcealed hostility, then each nodded stiffly.

De Moche turned to Kennedy as he passed down the hall.  “Perhaps it may have been sent to divert suspicion—­who can tell?” he whispered.

Kennedy nodded appreciatively, noting the change.

At the sound of Lockwood’s voice both Norton and I had taken a step further after them out into the hall, Norton somewhat in advance.  As de Moche disappeared for his lecture, Kennedy turned to me from Lockwood and caught my eye.  I read in his glance that fell from me to the mat that he wished me quietly to abstract the piece of paper which he had placed under it.  I bent down and did so without Lockwood seeing me.

“Why was he here?” demanded Lockwood, with just a trace of defiance in his voice, as though he fancied the meeting had been framed.

“I have been showing this to every one who might help me,” returned Kennedy, going back into the laboratory after giving me an opportunity to dispose of the shoe-prints.

He handed the anonymous letter and the other warnings to the young soldier of fortune, with a brief explanation.

“Why don’t they come out into the open, whoever they are?” commented Lockwood, laying the papers down carelessly again on the table.  “I’ll meet them—­if they mean me.”