The girls were obviously cold, standing idle now after their long flight. Mercer lost no time in preparing for the return journey. He tumbled his captives unceremoniously off the platform and set the box of food and blankets beside them. "What's this, Anina?" He was holding in his palm a tiny metal cylinder. Anina took it from him. "For fire, see?" She picked up a bit of driftwood, and, holding the end of the cylinder against it, pressed a little button. A curl of smoke rose from the wood, and in a moment a wisp of flame. "A light-ray!" Mercer exclaimed. "The ray--but different." She tossed the blazing bit of wood aside, and held her hand a foot or so in front of the cylinder. "No danger! See?" She brought her hand closer. "Heat here--close--no heat far away." Mercer understood then that this was not a light-ray projector, but a method of producing heat with the property of radiation, but not of projection--a different and harmless form of the ray. He took the little cylinder from the girl, inspected it curiously, then laid it on the blankets. "They'll need it, I guess, if it's any colder where they're going." He set one of the captives free. "Anina, tell him to sit quiet until we've gone. Then he can cut the others loose." He tossed a knife into the box. "Come on, Anina; let's get away." They were about ready to start back, when Mercer suddenly decided he was hungry. He hopped off the platform. "They don't need all that food." He gathered some of the little flat cakes of dough in his hands. "Want some?" He offered them to the girls, who smilingly refused. "All right. I do. I'm hungry. Might as well take a blanket, too. It's devilish cold." He was back on the platform in a moment, sitting down with the blanket about his knees and munching contentedly at the bread. "All right, Anina. Start her off." They swung up into the air and began the return flight. A few hours more and they would be back at the Great City. Then the real work would begin. Mercer squared his shoulders unconsciously as he thought of all there was to do. But there was no danger to the Light Country from Tao, he thought with satisfaction. At least, there would be none when the other cities were rid of Tao's men, as the Great City was now. The men would find their way back all right-- At the sudden thought that came to him Mercer dropped his bit of bread and sat up in astonishment. Tao no longer a menace? He remembered my reasoning in the boat coming down the bayou. Of course, Tao would have no reason to attack the Light Country by force of arms until he was sure his propaganda among the people had failed.