The polaroid windows in the opposite wall looked out upon a desolate scene. A barren, burning plain of blackened rock stretched beneath the stupendous glare of a blazing sun. The temperature out there was far above the terrestrial boiling point — for this was the famed Hot Side of Mercury, the hottest place in the Solar System.

Out there in the sun glare towered hundreds of huge, gleaming cylinders. They were monster photo-electric cells, colossal tubes lined with sodium, that drew torrents of electric power from the stupendous solar radiation that beat on this world. Heavy cables brought the power from the cells to this domed, air-tight central building, whence it was transmitted by high-frequency radio-beam to the other eight planets.

Stanton could hear voices from audio-phone-speakers all along the row of switch- boards, speaking from far-off worlds to the engineers and switch-men here at the Solar Station.

“Increase to ninety million kilos on the Pluto beam,” called the husky voice of a man on distant Pluto from a speaker.

Dial-needles jumped, and the great radio-electric generators in the lower levels of the Station building throbbed louder.

“Cut load on Neptune beam to one hundred and twenty million kilos,” another, shriller voice was calling from an audio-phone.