Robins, the wireless operator, bent closer over his instrument, and the blue fires flashed from the masthead of the steamer, cutting their way through the darkness into the black spaces beyond. The little room was lit by a dull oil light, the door was fast-closed and locked. Away into the night sped one continual message.

"Steamship City of Boston, lat…. long…. lying four points to northward of usual course. Reply."

A time came when the young man ceased from his labours and sat up with a yawn. He stretched out his hand and lit a cigarette, walked to the little round window which commanded the deck, gazed out of it steadily, and turned back once more to his chair before the instrument. Then something happened. A greater shock than any that lay in the blue lightning which he had been generating was awaiting him. His right hand was suddenly gripped and held on to the table. He found himself gazing straight down the black bore of a small but uncommonly ugly-looking revolver. A voice which seemed remarkable for its convincing qualities, addressed him.

"If you speak a word, Robins, move, or show signs of any attempt to struggle, I shall shoot you. I have the right and the power." Robins, a young man of nerve, whose name stood high on an official list of those who might be relied upon for any desperate enterprise, sat like a numbed thing. Dim visions of the face of this man, only a few feet away from his own, assailed him under some very different guise. It was Crawshay the man, stripped for action, whose lean, strong fingers were gripping the butt of that revolver, and whose eyes were holding him like gimlets.

"Now, if you are wise, answer me a few questions," Crawshay began. "I'd have brought the captain with me, but I thought we might do better business alone. You've been advertising the ship's whereabouts. Why?"

"I've only been giving the usual calls," the young man muttered.

"Don't lie to me," was the grim reply. "Your wireless was supposed to be silent from yesterday midday except for the purpose of receiving calls. I ask you again, why and to whom were you advertising our whereabouts and course?"

Robins looked at the revolver, looked at Crawshay, and was dimly conscious of a damp feeling about his forehead. Nevertheless, his lips were screwed together, and he remained silent.

"Come," Crawshay went on, "we'll have a common-sense talk. I am an agent of the British Secret Service. I have unlimited powers upon this ship, power to put a bullet through your head if I choose, and not a soul to question it. The game's up so far as you are concerned. You have received messages on this steamer of which you have kept no record, but which you have delivered secretly to a certain passenger. Of that I may or may not speak later on. At present I am more interested in your operations of to-night. You are signalling the information of our whereabouts for some definite reason. What is it? Were you trying to pick up the Blucher?"

"I wasn't trying to pick up anybody," the young man faltered.