They had to use every precaution in going after Foster. In the first place, they had to consider that he might be violently opposed to their project--that, in fact, he might go straight to the authorities with it. The only safeguard against that was simply to prevent Foster from knowing where their project was located. Without that information, he would probably find it difficult to make the authorities believe him. A mere story about mechanisms that control gravity, without any basis of fact to support it, would sound rather far-fetched. For that matter, it would have been difficult merely to visit Foster and convince him they did have such mechanisms! The only quick answer was to show him, to prove it to him. Then he would listen to them. There was a good chance that he'd approve of their project and help them with it--otherwise, Morrow wouldn't have thought of him. And he was a man who could help them. Robert Foster was a jet engineer, employed as a flight-test analyst at an aircraft corporation's experimental plant near Sacramento. Morrow had met him, however, because Foster had written many stories for the science-fiction magazines, mostly on the galactic empire theme. They had met at a private science-fiction club in New York and spent most of a long night in a bar, along with several other writers and magazine editors, discussing subjects of vast scope and consuming beverages in vast quantity. Foster had proved himself a kindred soul of fertile imagination, if not of superior intellect, and so into the wee, small hours. In short, Foster had impressed him as a man to be trusted when the going got rough. Whether or not that impression had been correct, Morrow didn't know. Tonight would certainly put it to the test. They could only ask for his help, and that was all. If he refused, he refused. They couldn't use threats or coercion or any suggestion of violence--that would gain them nothing. Foster _had_ to agree! There was no one else! Without his help, they were stymied.... The weather thickened as they turned west, coming down off the slopes of the Sierras. Silvery masses of cloud drifted by in the moonlight and a thin, gray haze obscured the ground. They cruised along, their tail-jets rumbling, descending slowly to pass beneath a long row of clouds ahead. Raindrops began streaking the transparent blister which pinged at their impact; then it began a steady, ringing sound as the downpour increased. The world was turned into a gray, trickling wetness, faintly reflecting the green glow of the luminous instrument dials. The lights of a town appeared off to the left, wavering sparks in the wet gloom. Smitty swore under his breath. They emerged from the shower to find themselves over an endless mass of cottony white, completely hiding the ground. "Now we gotta go down through that stuff!" Smitty muttered, and pushed the nose down.