"Which doesn't prove that no one else would use one."
"Anyhow, he was out until four A.M. last night and some one broke into
Phelps's house to—"
"You can't establish the fact that he went out there. There are plenty of other places he could have been until four in the morning."
"But I can assume—"
"If you are going to assume anything, Walter, why not assume he was the second man, the man who watched the actual intruder?"
I turned away, despairing of my ability to convince Kennedy. As a matter of fact I had forgotten the other prowler at Tarrytown.
Then I noticed that the one guinea pig in the separate cage was dead. In an instant I was all curiosity to know the results of Kennedy's investigations.
"Did you make any progress?" I asked.
"Yes!" Now I noticed for the first time that he was in fine humor. "I had quite finished the first stage of my analysis when you came in."
"Then what was it? What was the poison that killed Stella Lamar?" I glanced at the stiff, prone figure of the little animal.