He was silent a moment, evidently pondering mentally some question, then he said with the air of one who has arrived at a decision by which he will abide whatever comes, "And the first step is to show you something that I had hoped not to reveal. The very day of the murder I received a letter from Dick stating—but you had better read it yourself."
He took from his wallet a single sheet of notepaper which he handed me. It was dated from Chicago two days before the murder and written in Dick's unmistakable flowing hand.
"Dear Dad," it began.
"Philip Darwin has persecuted the Trenton family for the last time. I have a weapon to use against him which will free Ruth and myself from the bondage we are in to that cur. I am leaving for the East to-morrow and when my task is completed, I shall call upon you at Tarrytown.
"Your repentant son,
"Dick."
When I finished reading I looked across at Mr. Trenton, wondering if to him too had occurred the thought which possessed me. Could the weapon be murder and the answer to the problem the fact that Ruth was shielding her brother again? Then I shook my head.
"If Dick was in the study how did he get away without my seeing him?" I said aloud. "He couldn't vanish into thin air."
"Carlton!" The word was a cry. "No, no, he would not dare again!"
"What did he mean by weapon then?" I inquired bluntly.
"Not—not murder! I could not bear that! No. I am sure he meant that he had learned that Philip Darwin was his uncle," he said low.
"His uncle!" I gasped, horrified.
"Yes, his uncle. But not Ruth's, Carlton! No, no, she was no relation to him," he reassured me quickly.