“Eleven o’clock, tonight,” said Loy Rook. “You do this.”

He pressed the bottom of the bookcase between the two sections. Each portion swung outward like a door, revealing separate flights of narrow steps— one leading up, the other down.

“This opens a hidden door below,” explained Loy Rook. “Then my friend Luke Froy may come in.

Remember — you say nothing — only watch!”

Harry nodded. He accompanied Loy Rook back to the office. As chance would have it, Loy Rook invited him to a Chinese lunch, so Harry had no opportunity at that time to send his information to Rutledge Mann.

When they returned to the office, Loy Rook remained there. The afternoon wore along. At last, Harry’s chance came. Loy Rook announced that he was going upstairs to his apartment.

The Chinaman might return at any time. It would be bad policy to leave the office. He picked up the telephone and dialed the number of Mann’s office. He heard Mann’s voice answer.

“Hello,” said Harry. “Did you mail that package that I left at the hotel?… Oh, I see. You gave it to the night clerk… Yes… Eleven dollars was the price… For the watch; the Chinaware cost fifteen. The man said he would take it back at the store on Fourteenth Street… What’s that? I can’t hear you… Oh, I see…

Good-by.”

The spaces in the conversation had been timed for imaginary replies. Actually, Rutledge Mann did not speak a word while Harry was talking. In the course of his sentences, Harry had sent a definite message: