_Plunk, plunk, plunk_, went the grenades. Had the scientist failed? Had something happened to Michaelson? * * * * * The night was hideous with the yells of the Ogrum. Sensing victory, they were screaming with delight. Meanwhile, all over the roof of the temple, more of the gas grenades were exploding. The wind, which had quickened to a stiff breeze, swept much of the gas away. But not all of it. One whiff of it and a man lost half his efficiency. Three whiffs and he was asleep. A man in an officer's uniform crawled to Craig's feet, looked up at him. It was Captain Higgins. "I--I guess this is it," the captain said. "I guess so," Craig said miserably. The gas stung his lungs again and he coughed. Slowly, a little at a time, he could feel a deadly lassitude stealing over him. A weight was tugging at his knees, trying to force his legs to buckle. More than anything else in the world, he wanted to lie down and go to sleep. He fought against the impulse. From this threatened sleep a man would awaken all right--in the prison pen of the Ogrum, there to wait his turn to become a sacrifice to the sun. Two or three machine guns--no more--were still firing, holding off the Ogrum horde. When those guns stopped-- The flames of the burning city danced in the night. The air was heavy with smoke. The screams of the dinosaurs were louder, as if the great beasts were excited by the conflagration in the city of the Ogrum. Craig was vaguely aware that only two guns were firing. In spite of all his efforts to resist the impulse, he sank to his knees. The grenades continued to plunk on the roof. Only one gun was firing. Beside him, Craig saw that Margy Sharp had gone quietly to sleep. She looked like a little girl who is all tired out with play and has decided to lie down and take a nap. _Boom-boom! Boom-boom-boom!_ Five thudding explosions came through the night. They did not come from the temple, or near it. They were at least half a mile away. The sound lifted Craig to his feet. "Michaelson!" he screamed. He tried to look in the direction from which the sound of the explosions had come. The smoke was too heavy. He could not see. "Michaelson--" his voice was a whisper. "For God's sake, hurry!" There was no answer. Craig waited. No more explosions came. He sank to his knees, fighting against the impulse to sleep. He was dimly aware that the screams of the Ogrum had died into abrupt silence. No more grenades were plunking on the roof. He wondered if the Ogrum were preparing to charge the temple, to strike down all who had strength left to oppose them. He lifted himself up, looked over the edge. The Ogrum were no longer watching the temple. They were staring in the direction of the explosions. They had come out into the open. He could see little groups of them nervously looking in the other direction. * * * * *