"He may have chased him right across this island. Come on, it's no use wasting time here; let's try and pick up the trail."
Andy leapt upon the flat top of the rock and assisted his chum to follow his example. Both took it for granted that there was no further need for concealment.
From where they stood the ground had the appearance of a broad belt of flat rock, divided in all directions by narrow crevices, most of which could be jumped across with the greatest ease, while ahead was the first of a series of cliffs, which incircled the base of the peak of the island.
"Look!" exclaimed Ellerton, pointing to a little heap of brown canvas which was lying on the rock about thirty feet away. "There's your father's haversack."
The lad was right, for Mr. McKay had discarded the article as he commenced the pursuit of the fugitive. From this spot the mingled tracks of the hunter and the hunted were easily traced, by reason of the deposit of lava dust, which grew thicker as the lads advanced.
Suddenly they came to an abrupt halt. Almost at their feet began the treacherous slope, ending in the horrible fissure which had been the cause of Blight's death and Mr. McKay's disaster.
Although the still sliding dust and sand had almost hidden the traces of Mr. McKay's desperate struggle to save himself from the yawning pit, there remained sufficient evidences of the disappearance of the fugitive and his pursuer.
The faces of both lads grew pale. Andy was about to rush towards the brink of the abyss when Ellerton's detaining hand was laid upon his shoulder.
"It's nothing more or less than a trap," said he. "You'll——"
The sentence remained unfinished, for from the depths of the chasm a hollow voice that the lads hardly recognised as Mr. McKay's repeated the warning: