“Well, if he did not leave it by any of the routes we have mentioned, how could he have gone out?�
“That is just the puzzle, sir. There isn’t any way.�
“Well, if there isn’t any way to go out, he has not gone out. That’s a cinch!� It was Patsy, who had remained silent hitherto, who made this remark; and then, after a very short interval of silence, he added: “And if he did go out, it follows that there is a way for him to have done it.�
“Patsy,� said the detective, “that ingenious statement on your part deserves a medal. Now, Thomas?�
“Yes, sir.�
“Bring me the letters that you took to Mr. Lynne this morning. That announcement that he was to receive a caller must be contained in one of them.�
“Yes, sir. He said as much as that when he told me about it. Here they are, Mr. Carter.�
Thomas took four letters from a taboret beside the chair that Lynne was in the habit of using, and the very first one that the detective examined, addressed in a handwriting which Nick recognized instantly, was as follows:
“Dear Mr. Lynne: I shall call upon you to-morrow shortly after noon. You may expect me without fail; and also you may expect to hear something of vital interest to you, and to others, also.
“Wednesday.