"I should think that the Confederation of Earth would send help, particularly since the original invaders were outlaws from that planet," Staunton said. "How about it, friend Ripon? How are conditions back on Earth at this time?" Ripon straightened up and shook his shoulders. The glow in his eyes faded away, and the lines in his face deepened once more. "The Lunarians can look for no help from Earth until one thing is accomplished," he said. "I have been letting scientific enthusiasm make me lose sight of our reason for coming here. How are conditions on Earth, you ask? I can tell you in a single sentence. Unless we of Earth very quickly get a new supply of radium salts suitable for use with the Riesling Method, in a few weeks we all perish!" "I do not understand." In a few hasty phrases Ripon sketched the development of the terrible plague that was so swiftly robbing Earth of its inhabitants. At the end Staunton leaned back in his chair. "Such salts are available on the Moon in ample quantity," he said slowly, and something in the quality of his voice robbed the words of the reassurance they would otherwise have held, "but--they are all located well within the area of the Great Barrier. And the Lords of Gral-Thala would never let you have even a single milligram!" "Then there's only one thing to be done!" Larry stood up and began to peel off his space suit. "If someone will show me the way, I'll go into Gral-Thala and bring out as much of the radiatron extract as I can carry." "And I will go with you!" boomed Pyatt of Kagan. "By Gorton and Laila, mythical gods of the Moon, it will take more than a few of those cold-eyed tyrants to stop us!" XII Time was the thing that counted. The remorseless pressure of minutes and hours that passed and could never be recalled! The tyrants who lorded it over Gral-Thala had no weapons more deadly than the electronic guns that had been common on Earth two hundred years before. A battalion of troops from Earth, wearing armor of dura-steel and carrying ray-guns, could probably have overthrown the Invaders very quickly. But--there was no time! The toll of the Gray Death was increasing with each passing hour, back there on the Good Green Planet, and the little group on the Moon would have to do what they could without hope of assistance. They could not pause for proper preparations or careful planning. It was only half an Earth day after they had landed on the Moon, time enough to snatch a few hours' sleep, that Larry found himself moving up toward the surface in a slowly crawling cable car. Chotan already lay behind and far below them, and the oxygen indicator fastened to the sleeve of the space suit showed him that the air was thinning rapidly.