"Repulsion would have been the answer,” said Russ bitterly. “And the Lord knows we have it. Plenty of it."
"Too much,” observed Wilson, smoke drooling from his nostrils.
"Not too much,” corrected Greg. “Inefficient control. You jump at conclusions, Wilson."
"The math didn't show that progressive action,” said Russ. “It showed repulsion, negative gravity that could be built up until it would shoot the ship outside the Solar System within an hour's time. Faster than light. We don't know how many times faster."
"Forget it,” advised Greg. “The way it stands, it's useless. You get repulsion by progressive steps. A series of squares with one constant factor. It wouldn't be any good for space travel. Imagine trying to use it on a spaceship. You'd start with a terrific jolt. The acceleration would fade and just when you were recovering from the first jolt, you'd get a second one and that second one would iron you out. A spaceship couldn't take it, let alone a human body."
"MAYBE this will do it,” said Wilson hopefully.
"Maybe,” agreed Russ. “Anyhow we'll try it. Equation 578."
"It might do the trick,” said Greg. “It's a new approach to the gravity angle. The equation explains the shifting of gravitational lines, the changing and contortion of their direction. Twist gravity and you have a perfect space drive. As good as negative gravity. Better, perhaps, more easily controlled. Would make for more delicate, precise handling."
Russ laid down the sheaf of papers, lit his pipe and walked to the apparatus.
"Here goes,” he said.