Suddenly Blight stumbled, kicking up a cloud of pumice dust that looked silvery in the moonlight. Two yards he traversed ere he fell headlong in the soft lava, and before he could stagger to his feet his pursuer was almost within arm's length.
"Give in, you idiot," shouted Mr. McKay, drawing his revolver.
For answer Blight laughed, and, bending low as he ran, he doubled away to the right, where the ground sloped downwards towards a line of irregularly-shaped cliffs. He was crippled. He had twisted his ankle, and everything was in Mr. McKay's favour.
Unwilling to close with the desperate fugitive, Mr. McKay prepared to maim him with a bullet through his leg; but even as he levelled the weapon, Blight disappeared from sight with a shriek of terror.
Instinctively Mr. McKay threw himself flat on his back, digging his heels into the soft yielding dust; but surely and gradually he found himself slipping towards the mouth of a gaping abyss. The very ground on which he was sprawling was moving. He could hear the rustle of the sand and small stones as they dropped over the ledge into the apparently fathomless chasm.
Desperately Mr. McKay plunged his arms into the sliding sand; but his efforts were unavailing. He was being launched towards the yawning gulf, the horrors of which seemed worse in the moonlight.
Just as he was on the point of slipping over the edge—his heels were already over the abyss—his hand, buried arm's length in the pumice, came in contact with a piece of hard rock.
Would it hold? he wondered.
Slowly his outstretched arm began to change from a vertical to an almost horizontal position as his body still continued its downward motion. The rock afforded but a slender hold: either the fabric might become loosened, or his hand might be unable to keep up the strain, and then——?
Mr. McKay ceased to struggle. He could feel the sand slipping from under him, streaming past like a solid cataract. So long as he kept quiet he was comparatively safe, but directly he commenced to find a foothold, his peril increased threefold. Yet he knew that every moment his grip upon the small pinnacle that stood between him and instant death was gradually becoming weaker.