"But this is different, Mr. Farnum. I refuse to obey any order that will tend to defeat the ends of justice."
Jacob Farnum winced at that statement of the matter. He had been anxious only to save Jack from the attempts of a dangerous crowd.
"Jack is right," broke in David Pollard, decisively.
"When he puts the case in that way, I don't dare say that he isn't," admitted the shipbuilder. "At the same time, I can't bear the thought of the lad being butchered to gratify the grudge of any of the rascally crew that we've offended here at Spruce Beach."
A slight, rustling sound at the door caused them all to wheel about. Jacob Farnum's eyes beheld a slip of white paper lying on the floor, just inside the door. Jack Benson saw it, also, but he sprang past the paper, pulling the door open.
Around a turn in the corridor the submarine boy heard the sound of fleet footsteps.
Jack pursued, but could find no one, and the sound of moving feet had also ceased. As soon as he was satisfied that he could not catch the prowler, the submarine boy returned to the room.
"Do you see this?" asked the shipbuilder, holding out the slip of paper.
"Another warning, I suppose?" Benson ventured.
"Yes; and it shows that you are being followed and watched. Something worse is almost certain yet to happen."