He listened to the animal calls in the forest and to the strange crashings of the underwood as the creatures broke cover and in vain sought safety.
Mingled with these sounds were others--yells, shrieks, and gibberings--the tumult of the perishing Horde.
Swiftly the fire spread to right and left, even as it ate northward from the river.
The mass of Anthropoids inevitably found themselves trapped; their slouching, awkward figures could here or there be seen in some clear space, running wildly. Then, with a gust of flame, that space, too, vanished, and all was one red glare.
The riflemen, meanwhile, were steadily potting such of the little demons as still were crawling up or down the cliffside opposite. Surely, relentlessly, they shot the invaders down. And, even as Stern watched, the enemy melted and vanished before his eyes.
Allan was thinking.
"What may this not result in?" he wondered as he observed the swift and angry leap of the forest-fire to northward. "It may ravage thousands of square miles before rain puts an end to it. It may devastate the whole country. A change in the wind may even drive it back on us, across the river, sweeping all before it. This may mean ruin!"
He paused a moment, then said aloud: "Ruin, perhaps. Yes; but the alternative was death! There was no other way!"
Now none of the attackers remained save a few feebly twitching, writhing bodies caught on some protuberance of rock. Here, there, one of these fell, and like the rest was borne away down stream.
Through the heated air already verberated a strange roar as the forest-fire leaped up the opposite hillside in one clear lick of incandescence. This roar hummed through the heavens and trembled over the long reaches of the river.
The fire jumped a little valley and took the second hill, burning as clear as any furnace, with a swift onward, upward slant as the wind fanned it forward through the dry brush and among the crowded palms.
Now and then, with a muffled explosion, a sap-filled palm burst. Here, or yonder, some brighter flare showed where the fire had run at one clear leap right to the fronded top of a fern-tree.
Fire-brands and dry-kye, caught up by the swirl, spiralled through the thick air and fell far in advance of the main fire-army, each outpost colonizing into swift destruction.
Already the nearer portion of the opposite cliff-edge was barren and smoking, swept clean of life as a broom might sweep an ant-hill. Tourbillons of dense smoke obscured the sky.
The air flew thick with brands, live coals and flaring bits of bark, all whirling aloft on the breath of the fire-demon. Showers of burning jewels were sown broadcast by the resistless wind.