Without intermission the lurid flashes darted downwards and disappeared amongst the foliage, each shaft doubtless working havoc with those giant trunks. From the point our heroes looked, however, they could only watch the forked streaks of brightness disappear amongst that yielding blackness. High above the rolling clouds reflected this vivid discharge with a ghostly pallor, while the avalanche of driving rain in the distance seemed a swirling curtain of blue and silver gauze. Loud and quick thunderclaps resounded, one peal after another, like the rolling of a hundred batteries of artillery. For fully half an hour the flames and the loud rattle of thunder went on without a break. They were above this aerial fire-ship, and could overlook its dark upper side from which no flashes came. Over it spread a mighty shadow, moving as it sailed like a black opening in the sky. It was driving rapidly towards them, and looked as if it soon must strike against the cliffs. As yet no wind or rain had reached them; yet they could see the tempest coming, although there was perfect stillness around them. They held on to the rocks, and watched the approach of this death-dealing cloud with fascinated eyes. All at once it took an upward sweep, as if drawn suddenly from above. As it did so, the firing seemed to slacken and become irregular. Now it was passing over their heads and driving along with the speed of an express train. At it flew by, it dropped a fire-ball into a large tree that grew a short distance from where they stood. Like a reed, the gigantic trunk bent over the edge, and disappeared with a sound like a shuddering sob. When the next flash came, they saw a great blank where the tree had stood, with a rift in the rocks as if a ton of dynamite had exploded there. Now the rain and the wind were on them with terrific fury. The thunder-cloud was miles away, pouring desultory and wanton shots on to the plateau, as it raced towards the far-off mountains. In an instant of time they were drenched, while the tornado shrieked through the rock-rifts like a thousand vengeful furies. The Kaffirs pitched themselves face downwards, and clutched to the jutting stones, for nothing mortal could have stood upright before that blast in its first force. Our heroes crouched under the shelter of a buttress-like boulder and watched, still fascinated, that disappearing fire-cloud. In a few minutes, from the little mound ran a hundred streams and tiny cascades into the hollows. These speedily became like filled moats, which swelled upwards until the mound became an island. Then the wind and the rain left them as suddenly as they had come. The sky once more cleared and the stars burnt with increased lustre. But their fire had been put out, and for that night, at least, could not be relighted. Luckily, day was not far off, therefore they formed a square outside their packages, and stood at attention while they waited for the dawn. CHAPTER TWENTY THREE.