Bordman did not consider himself a scientist, but he winced. Riki raged as they moved over the slippery ice. Her breath was an intermittent cloud about her shoulders, and there was white frost on the front of her cold-garments. Even so quickly the moisture of her breath congealed. He held out his hand quickly as she slipped, once. "But they'll beat it!" said Riki in a sort of angry pride. "They're starting to build more landing-grids, back home. Hundreds of them! Not for ships to land by, but to draw power from the ionosphere! They figure that one ship-size grid can keep nearly three square miles of ground warm enough to live on. They'll roof over the streets of cities and pile snow on top for insulation. Then they'll plant food-crops in the streets and gardens, and do what hydroponic growing they can. They're afraid they can't do it fast enough to save everybody, but they'll try!" Bordman clenched his hands inside their bulky mittens. "Well?" demanded Riki, "Won't that do the trick?" "No." "Why not?" "I just took readings on the grid, here. The voltage and the conductivity of the layer we draw power from, both depend on ionization. When the intensity of sunlight drops, the voltage drops and the conductivity drops too. It's harder for less power to flow to the area the grid can tap--and the voltage pressure is lower to drive it." "Don't say any more!" cried Riki. "Not another word!" Bordman was silent. They went down the last small slope, and passed the opening of the mine, a great drift which bored straight into the mountain. Looking into it, they saw the twin rows of brilliant roof-lights going toward the heart of the stony monster. They had almost reached the village when Riki said in a stifled voice: "How bad is it?" "Very," admitted Bordman. "We have here the conditions the home planet will have in two hundred days. Originally we could draw less than a fifth the power they count on from a grid on Lani II." Riki ground her teeth. "Go on!" she said. "Ionization here is down ten per cent," said Bordman. "That means the voltage is down, somewhat more. A great deal more. And the resistance of the layer is greater. Very much greater. When they need power most, on the home planet, they won't draw more from a grid than we do now. It won't be enough." They reached the village. There were steps to the cold-lock of Herndon's office-hull. They were ice-free, because like the village walk-ways they were warmed to keep frost from depositing on them. Bordman made a mental note. In the cold-lock, the warm air pouring in was almost stifling. Riki said defiantly: "You might as well tell me now!"