“Sir!” he cried to the commander of the vessel, “Miss Beulow has been accused by Lieutenant Taylor and arrested on the Alto as a German spy!”

“What!” shouted Lord Hastings.

“Arrested!” cried Frank.

“Yes, sir,” replied the operator. “I just this moment received the message.”

“Come with me,” commanded Lord Hastings, and the three made a rush for the wireless room.

Just as they neared the room, the form of a man emerged hastily from the door, and, noting their approach, ran hurriedly along the deck. Paying no heed to the disappearing man, the three ran into the room. Here Lord Hastings dashed off a message, which he handed to the operator.

“Send this!” he commanded.

The message read:

“Release the girl. Arrest Lieutenant Taylor. He is the spy. Explanation follows.”

The operator took his place beside his instrument, but, after one touch of the key, sprang to his feet.