“Then you mean——?”
“That calculating by our watches Ito poisoned Tilghman at noon and an hour later, which by our time would be one o’clock, and by Atlanta time would be noon, was in the library. Thus he had ample opportunity to commit the crime and establish a perfectly good alibi at the Atlanta library.”
“But the Atlanta librarian telegraphed he was there at noon——”
“Of course, he was going by central time which, as I have just mentioned, prevails in Atlanta. We have been going by our watches which are one hour ahead of Atlanta. And between us we have muddled things up finely.”
“Let me get this clear!” Barclay rumpled his hair with both hands. “Going by Atlanta time, Ito poisoned Tilghman at eleven o’clock this morning, and was at the library at twelve?”
“Exactly.”
“But by the time prevailing on this train and our watches, Ito poisoned Tilghman at twelve o’clock and was at the library at one—and relying on our forgetting in our excitement the difference of time, handed us a perfectly good alibi.”
“You’ve put it in a nutshell.” Norcross rose. “The only opportunity the murderer had of entering the smoker unobserved was during the first twenty minutes following the train’s arrival in Atlanta. After that Shively and I stood in the vestibule smoking, while the porter was standing at the other end of the car until the train pulled out of the station.”
“How did you happen to think of the difference in time?” asked Barclay detaining the professor.
“Shively observed the hour stamped on the Atlanta telegram and commented on the fact that it was sent before he had wired, then we looked up the question of time, and that gave us the clew. To think of Ito putting it over on us.” The professor clenched his fists. “I’d like to put my hands on him.”