“Thieves?” she asked in a whisper.

“I’m almost sure of it,” he answered in the same tone. “I heard a boat bump against the side of the Wisp a few minutes ago. I think they were drifting down with the tide to reconnoitre, and were swept in closer than they had expected to be.”

“Have you a pistol?”

“On the locker there. Lucky Danton lent me one of his. You aren’t afraid?”

“Not—with you.”

“I dare say they won’t come back. Listen now! See if you can make out anything to starboard. I’ll watch on this side.”

The night was very dark. The stars were obscured by light clouds, nor was there a moon visible. Their eyes could penetrate the darkness little farther than the rails where a whitish mist hid the surface of the water.

Betty gazed intently. A sidelong glance showed her Fessenden kneeling on the locker opposite her, his half-bared arms folded on his chest. His powerful form gave her a comforting sense of protection. She stared again to starboard.

From the mist two great hands gripped the rail of the sloop! Then a face—the face of a negro—rose into view, a knife gripped in his teeth. So impossible, so barbaric, did the apparition seem, that for a long breath Betty stared spell-bound.

Then her scream whirled Fessenden about. He crossed the cockpit at a bound, and struck savagely at the negro’s jaw. The latter ducked with the skill of a trained boxer. Throwing up a hand, he caught the other by the throat, dragging him forward.