Darrow had climbed a matter of twenty feet.

Now the seamen distributed themselves for more leisurely and accurate marksmanship.  Handy Solomon lay flat on his stomach, resting the rifle muzzle across the top of a sand dune.  Pulz sat down, an elbow on either knee for the greater steadiness.  The Nigger knelt; but Thrackles remained on his feet.  No rest could be steadier than the stone-like rigidity of his thick arms.

The firing now became miscellaneous.  No one paid any attention to anyone else.  Each discovered what I could have told them, that even the human figure at five hundred yards is a small mark for a strange rifle.  The constant correction of elevation, however, brought the puffs of dust always closer, and I could not but realise that the doctrine of chances must bring home some of the bullets.  I soon discovered by way of comfort that only Thrackles and Handy Solomon really understood firearms; and of those two Thrackles alone had had much experience at long range.  He told me afterward he had hunted otter.

About halfway up the cliff Thrackles fired his fifth shot.  No dust followed the discharge; and I saw Percy Darrow stagger and almost lose his hold.  The men yelled savagely, but the assistant pulled himself together and continued his crawling.

The sun had been shining in our faces.  I could imagine its blurring effect on the sights.  Now abruptly it was blotted out, and a semi-twilight fell.  We all looked up, in spite of ourselves.  An opaque veil had been drawn quite across the heavens, through which we could not make out even the shape of the sun.  It was like a thunder cloud except that its under surface instead of being the usual grey-black was a deep earth-brown.  As we looked up, a deep bellow stirred the air, which had fallen quite still, long forks of lightning shot horizontally from the direction of the island’s interior, and flashes of dull red were reflected from the canopy of cloud.

The men stared with their mouths open.  Undoubtedly the change had been some time in preparation, but all had been so absorbed in the affair of the doctor’s assistant that no one had noticed.  It came to our consciousness with the suddenness of a theatrical change.  A dull roaring commenced, grew in volume, and then a great explosion shook the very ground under our feet.

We stared at each other, our faces whitening.

“What kind of hell has broke loose?” muttered Pulz.

The Nigger fell flat on his face, uttering deep lamentations.

“Voodoo!  Voodoo!” he groaned.

A gentle shower of white flakes began, powdering the surface of everything.  Far out to sea we could make out the sun on the water.  Gradually the roaring died down; the lightning ceased.  Comparative peace ensued.  We looked again toward the cliff.  Percy Darrow had not for one instant ceased to climb.  He was just topping the edge of the bluff.  Handy Solomon, with a cry of rage, seized another rifle and emptied the magazine at him as fast as the lever could be worked.  The dust flew wild in a half dozen places.  Darrow drew himself up to the sky line, raised his hat ironically, and disappeared.