Chet glanced above him. "Come down, Kreiss!" he ordered. "Get down here, quick! This is the finish. We could have licked them on land, but these others will get us." He stood, dumb with amazement, as he saw the thin figure of Kreiss leap excitedly from his rocky perch and vanish like a terrified rabbit into the cave in the rocks. "I didn't think--" he was telling himself in wondering disbelief at this cowardice, when Kreiss reappeared. His one hand was white with a rubbery coating that Chet vaguely knew for latex. He was holding a gray, earthy mass, and he threw himself forward to the catapult where it stood idly erect in the wind that beat and whipped at it. "Help me!" It was Kreiss who ordered, and once more he spoke as if he were conducting only an interesting experiment. "Pull here! Bend it--bend it! Now hold steady; this is metallic sodium, a deposit I found deep in the earth." The gray mass was in the crude bucket of the machine. Kreiss' knife was ready. He slashed at the vine that he'd the bent sapling, and a gray mass whirled out into the dark; out and down--and the inky waters were in that instant ablaze with fire. [Illustration: _The inky waters were ablaze with fire._] Fire that threw itself in flaming balls; that broke into many parts and each part, like a living thing, darted crazily about; that leaped into the air to fall again among ape-men who screamed frenziedly in animal terror. * * * * * "It unites with water," Kreiss was saying: "a spontaneous liberation and ignition of hydrogen." The white-coated hand had dumped another mass into the primitive engine of war. "Now pull--so--and I cut it!" And the leaping, flashing fires tore furiously in redoubled madness where a shrieking mob of terrified beasts, and one white man among them, drove ashore beyond the end of a barricade. Chet felt Harkness beside him. "We drove 'em off in back. What the devil is going on here?" Walt was demanding. But Chet was watching the retreat of the blacks straight off and down the shore where the sand was smooth and neither grass nor trees could hinder their wild flight. "You've got them licked," Harkness was exulting: "and we've cleaned them up on our side. Just came over to see if you needed help." "We sure would have," said Chet; "more than you could give if it hadn't been for Kreiss." "We've got 'em licked!" Harkness repeated wonderingly; "we've won!" It was too much to grasp all at once. The victory had been so quick, and he had already given up hope. The two had clasped hands; they stood so for silent minutes. Chet had been nerved to the point of destroying his companions and himself; the revulsion of feeling that victory brought was more stupefying than the threat of impending defeat. * * * * *