"Our present course will take us very close to Europa, which the hexans believe to be like Ganymede, entirely devoid of civilized life. Its original humanity was totally destroyed, and all its civilized hexans are finding shelter from our torpedoes upon Jupiter until we of Callisto shall likewise have been annihilated. The temperature of Europa will suit you. Its atmosphere, while less dense than that to which you are accustomed, will adequately support your life. If we are not detected in the course of the next few hours we can probably land upon Europa in safety, since its neighborhood is guarded but loosely. In fact, we have a city there, as yet unsuspected by the hexans, in which our scientists will continue to labor after Callisto's civilization shall have disappeared. We think that it will be safe to use your power for the short time necessary to effect a landing. We shall land in a cavern, in a crater already in communication with our city. In that cavern, instructed and aided by some of us, you will build a rocket vessel--no rays can be used because of the hexans--in which you will be able to travel to a region close enough to your earth so that you can call for help. You will not be able to carry enough fuel to land there--in fact, nearly all the journey will have to be made without power, traveling freely in a highly elongated orbit around the sun--but if you escape the hexans, you should be able to reach home safely, in time. It is for the consideration of this plan that this meeting has been called." * * * * * "Just one question," Breckenridge spoke. "The hexans are intelligent. Why are they leaving Europa and Ganymede so unguarded that human beings can move back there and that we can land there, all undetected?"