They made several plates, continuing their observations until all the planets had been located, even old Pluto, where crews of Nigran technicians were obviously at work, building giant structures of lux metal. The great cities of the Nigrans were beginning to bloom on the once bleak plains of the planet. The mighty blaze of Sirius had warmed Pluto, vaporizing its atmosphere and thawing its seas. The planet that the Black Star had stolen from the Solar System was warmer than it had been for two billion years. "Well, that's it," said Arcot when they had finished taking the necessary photographs. "We can prove we went faster than light easily, now. The astronomers can take up the work of classifying the planets and getting details of the orbits when we get back. "Since the Nigrans now have a sun of their own, there should be no reason for hostility between our race and theirs. Perhaps we can start commercial trade with them. Imagine! Commerce over quintillions of miles of space!" "And," interrupted Wade, "they can make the trip to this system in less time than it takes to get to Venus!" "Meanwhile," said Morey, "let's get on with our own exploration." They strapped themselves into the control seats once more and Arcot threw in the molecular drive to take them away from the sun toward which they had been falling. When the great, hot disc of Sirius had once more diminished to a tiny white pinhead of light, Arcot turned the ship until old Sol once more showed plainly on the cross-hairs of the aiming telescope in the rear of the vessel. "Hold on," Arcot cautioned, "here we go again!" Again he threw the little red tumbler that threw a flood of energy into the coils. The space about them seemed to shiver and grow dim. Arcot had thrown more power into the coils this time, so the stars ahead of them instead of appearing violet were almost invisible; they were radiating in the ultra-violet now. And the stars behind them, instead of appearing to be green, had subsided to a dull red glow. Arcot watched the dull red spark of Sirius become increasingly dimmer. Then, quite suddenly, a pale violet disc in front of them ballooned out of nowhere and slid off to one side. The spaceship reeled, perking the men around in the control seats. Heavy safety relays thudded dully; the instruments flickered under a suddenly rising surge of power--then they were calm again. Arcot had snapped over the power switch. "That," he said quietly, "is not so good." "Threw the gyroscopes, didn't it?" asked Morey, his voice equally as quiet. "It did--and I have no idea how far. We're off course and we don't know which direction we're headed." VI "What's the matter?" asked Fuller anxiously.