Borden moved an emergency light to shine on the output meter. The needle was fast against the pin. The feed-back screen was not only drawing maximum safe power. It was working on an effective short circuit of the ship's entire power supply. Busbars carrying that current would be heating up. They would melt at any instant. Borden's fingers moved swiftly. He set up a shunt for on-switch operation of the feed-back field. He threw the last cross-over tumbler and waited, with sweat beading his forehead. Something had flung a beam of pure heat-energy at the _Danaë_. It should have volatized the small space-craft immediately, but it had been left on for four seconds. When it ended, the feed-back screen cut off, too. Then the _Danaë_ had been detected a second time and the planetary weapon used again. Now, with the feed-back field on-switch instead of relay, _if_ the heat ray turned off again the feed-back field wouldn't, and the _Danaë_ should be indetectable to anything but a permeability probe. The space-ship would seem to have been destroyed, if the heat-beam went off before the ship's power failed. * * * * * It did. A relay clicked somewhere, cut a current flow of some tens of thousands of amperes. The lights inside the ship flashed to full brightness. Borden's eyes flicked to the power-meters. The operational power-tank meter read zero. The emergency reserve power-tank meter showed a reading that made fresh sweat come out on Borden's face. But the ports stayed black. Absolutely any form of energy striking the feed-back field outside would be neutralized. No light would be reflected. Any detector-field would be exactly canceled, as if nothing whatever existed where the _Danaë_ hurtled onward some few hundred miles above the planet's surface. The _Danaë_, at the moment, was in the position of having made a hole about itself to crawl into. But it couldn't use its drive. It couldn't see out. It was hiding in blackness of its own creation, like a cuttlefish in its own ink. "Dee," Ellen Borden asked her husband in a shaky voice, "what happened?" "Something threw a heat-ray at us," said Borden. He mopped his forehead. "We should have exploded to incandescent gas. But our feed-back field stopped it. The heat-ray cut off when we should have been destroyed--and so did our field, so there we were again! And so we got a second beaming. But now we aren't. At least we appear not to be. So we can live until we crash." Sattell said in a suddenly high-pitched voice, "How long will that be?" "I don't know the gravity," Borden told him. "But it does take time to fall four hundred miles. We have some velocity, too. It's under orbital speed but it'll help. I'm going to figure something out."