He looked at the panel she indicated, and saw as through a powerful telescope, a side view of the great lunar crater which he had learned to recognize as Copernicus. Shooting upward from the center of the crater was a bright band of green light. “Now look at this picture,” continued Maza, pointing to another panel. He looked, and saw a telescopic view of the earth. Despite the many storm areas which hid outlines of land and water, he made out the shape of North America, and saw that Washington and the territory surrounding it were in an immense spot of green light. “What can those rays do at that distance?” he asked Vanible Khan. “That,” replied the lunar scientist, thoughtfully stroking his long white beard, “depends wholly on the power of the ray projector which P’an-ku is employing. If powerful enough, the green rays will contract and destroy all matter which they come in contact. When nearly spent, they still have the power to remove much of the heat from everything they touch. I should say, off hand, that the area they reach at present is intensely cold—perhaps even uninhabitable for human beings.” Ted turned suddenly to Maza. “May I have a glass helmet and a suit of insulated armor?” he asked. “My own suit is useless until I can fit a new helmet to it.” “You may, of course. But where are you going?” “To destroy that green ray projector.” “Ten thousand of my _nak-kar_ cavalry will fly with you,” she said. “You are very kind to offer help,” he replied, “but I prefer to go alone. This is my war and my people are being killed.” “You refuse?” He could see that she was nettled. “I decline with sincere thanks, if you please. Time is precious, and in my vehicle I can reach the projector before your flying beasts are well on the way, thereby saving many lives which otherwise might be sacrificed by delay.” “Very well. It is your war now, because I have not yet officially declared war on P’an-ku. I will do so immediately. Then, if we cannot be allies, I will fight him in my way and you in yours.” She turned to one of the armored nobles who stood nearby. “See that Ted Dustin is outfitted for surface flying at once,” she commanded. Fifteen minutes later, Ted stood on the roof of the palace attired in the bell-like glass helmet and white, wooly, insulated armor of Maza’s people. He fidgeted impatiently while a great _nak-kar_ was being saddled in order that its rider might guide him up through one of the huge and tortuous air shafts which led from the subterranean city of Ultu to the ringed plain of Tycho above. At his side stood Vanible Khan, stroking his long white beard and coolly supervising the preparations. When the flying dragon was saddled and its rider seated, the old scientist placed his hand on Ted’s shoulder, and said: