The boatswain ceased speaking, and Syd stood laughing to himself, but treasuring up what had been said, as the wind swept overhead, and the waves kept on thundering in over the natural pier; though strangely enough the noise of the waves at this end of the gap also passed right up and away, so that it was possible to talk in a low tone, and hear the slightest sound anywhere near.

They had been standing like this for some time when Syd suddenly laid his hand on the boatswain’s arm.

“What’s that?” he said, in a low whisper.

“Dunno, sir,” whispered back the boatswain. “Trying to make out. I heard it twyste afore. What did it sound like to you?”

“One stone striking against another.”

“That’s it, sir, exact. Don’t say any more here. It’ll only scare yon chap. Sailors is easily frightened ’bout what they don’t understand.”

They stood listening for some few minutes, but there was no farther sound, so they bade the man on guard keep a sharp look-out, though for what Syd could not have said, and turned to go up to the tent and see if Mr Dallas was awake.

As they approached the place where the fire had been, a faint waft of the wind passed down the gap, and as it swept over the embers they brightened up, and shed sufficient light for Syd to see something creeping softly by the spot.

Syd caught the boatswain’s arm, and a gentle tap from the rough fellow’s hand seemed to express that he knew, and had noticed. This was so evidently the object that had twice before been seen, that now was the time to convince themselves whether it was human, or some quadruped dwelling on the rock.

“If I whisper,” thought Syd, “it will take alarm, I know.”