came down the wind; it maintained itself for a few seconds, ceased, and then came again, and continued at uneven intervals longer than the timed blasts of Number 25's whistle. It might be the horn of some struggling sailing vessel, which in spite of the storm and the closed season was braving the seas; at the end of each interval of silence, the horn blew twice now; the echo came abeam, passed astern, and was no longer to be heard. How far away its origin had been, Alan could only guess; probably the sailing vessel, away to windward, had not heard the whistle of Number 25 at all.
Alan saw old Burr who, on his way to the wheelhouse, had halted to listen too. For several minutes the old man stood motionless; he came on again and stopped to listen. There had been no sound for quite five minutes now.
"You hear 'em?" Burr's voice quavered in Alan's ear. "You hear 'em?"
"What?" Alan asked.
"The four blasts! You hear 'em now? The four blasts!"
Burr was straining as he listened, and Alan stood still too; no sound came to him but the noise of the storm. "No," he replied. "I don't hear anything. Do you hear them now?"
Burr stood beside him without making reply; the searchlight, which had been pointed abeam, shot its glare forward, and Alan could see Burr's face in the dancing reflection of the flare. The man had never more plainly resembled the picture of Benjamin Corvet; that which had been in the picture, that strange sensation of something haunting him, was upon this man's face, a thousand times intensified; but instead of dis-
