"Oh, no! I am their captive, as are all my people. We are but slaves of the tall ones." Brand glanced at Dex. "Here's a chance to get some information, perhaps," he murmured. Dex nodded; but meanwhile the girl had caught his thought. She smiled--a tragic, wistful smile. "I shall be happy to tell you anything in my power to tell," she informed him. "But you must be quick. I can only remain with you a little while." She sat down on the floor with them--the few bench-like things obviously used by the tall creatures as chairs were too high for them--and with the informality of adversity the three captives began to talk. Swiftly Brand got a little knowledge of Greca's position on Jupiter, and of the racial history that led up to it. * * * * * Four of the nine satellites of Jupiter were now the home of living beings. But two only, at the dawn of history as Greca knew it, had been originally inhabited. These were the fourth and the second. On the fourth there dwelt a race, "like me," as Greca put it--a kindly, gentle people content to live and let live. On the second had been a race of immensely tall, but attenuated and physically feeble things with great heads and huge dull eyes and characters distinguished mainly for cold-blooded savagery. The inhabitants of the fourth satellite had remained in ignorance of the monsters on the second till one day "many, many ages ago," a fleet of clumsy ships appeared on the fourth satellite. From the ships had poured thousands of pipe-like creatures, armed with horrible rods of metal that killed instantly and without a sound. The things, it seemed, had crowded over the limits of their own globe, and had been forced to find more territory. They had made captive the entire population of the satellite. Then--for like all dangerous vermin they multiplied rapidly--they had overflowed to the first and fifth satellites--the others were uninhabitable--and finally to the dangerous surface of Jupiter itself. Everywhere they had gone, they had taken droves of Greca's people to be their slaves, "and the source of their food," added Greca, with a shudder; a statement that was at the moment unintelligible to the two men. * * * * * Brand stared sympathetically at her. "They treat them very badly?" he asked gently. "Terribly! Terribly!" said Greca, shuddering again. "But you seem quite privileged," he could not help saying.