The hill of sand that sheltered them vanished to sweep in a sheet above their heads. And the air struck down with terrific weight, then left them in an airless void that seemed to make their bodies swell and explode. It rushed back in a whirling gale to sweep showers of sand and pebbles over the helpless forms of the three who lay battered and stunned. An instant that was like an age; then the scientist pointed with a weak and trembling hand where a towering spire of metallic gray leaned slowly in the air. So slowly it moved, to the eyes of the watchers--a great arc of gathering force and speed that shattered the ground where it struck. "The gun!" was all that the still-dazed lieutenant could say. "The--the gun!" And he fell to shivering uncontrollably, while tears of pure happiness streamed down his face. The mammoth siege gun--the only weapon for bombardment of the helpless Earth--was a mass of useless metal, a futile thing that lay twisted and battered on the sands of the sea. * * * * * The submarine now showed at a distance; it had withdrawn, by prearrangement, to the shelter of the deeper water. McGuire looked carefully at the watch on his wrist, and listened to make certain that the explosion had not stopped it. Sykes had told him the length of the Venusian day--twenty hours and nineteen minutes of Earth time, and he had made his calculations from the day of the Venusians. And, morning and night, McGuire had set his watch back and had learned to make a rough approximation of the time of that world. The watch now said five-thirteen, and the sun was almost gone; a line of gold in the western sky; and McGuire knew that it was a matter only of minutes till the blast of the big gun would rock the island. One heavy section of the great barrel was resting upon the shattered base, and McGuire realized that this blocking of the monster's throat must mean it would tear itself and the island around it to fragments when it fired. He ran toward the beach and waved his arms wildly in air to urge on the speeding craft that showed dim and vague across the heaving sea. It drove swiftly toward them and stopped for the launching of the little boat. There was a delay, and McGuire stood quivering with impatience where the others, too, watched the huddle of figures on the submarine's deck. It was Althora who first sensed their danger. Her voice was shrill with terror as she seized McGuire's arm and pointed landward. "Tommy--Tommy!" she said. "They are coming! I saw them!" * * * * * A swarming of red figures over the nearby dunes gave quick confirmation of her words. McGuire looked about him for a weapon--anything to add efficiency to his bare hands--and the swarm was upon them as he looked. He leaped quickly between Althora and the nearest figures that stretched out grasping hands, and a red face went white under the smashing impact of the flyer's fist.