There, on the third level, he entered a Mecho restaurant, sat down at a table and ordered from the robot waiter, pushing ivory-tipped buttons on the menu before him.

He ate leisurely, smoked ferociously, thinking. Looking at his watch, he saw that it was nearly two o'clock. He walked to the cashier machine, inserted the metallic check with the correct change and received from the clicking, chuckling register the disk that would let him out the door.

"Thank you, come again," the cashier-robot fluted.

"Don't mention it," growled Wilson.

Outside the restaurant he walked briskly. Ten blocks away he came to a building roofing four square blocks. Over the massive doorway, set into the beryllium steel, was a map of the Solar System, a map that served as a cosmic clock, tracing the movement of the planets as they swung in their long arcs around the Sun. The Solar System was straddled by glowing, golden letters. They read: INTERPLANETARY BUILDING.

It was from here that Spencer Chambers ruled his empire built on power.

Wilson went inside.

CHAPTER FOUR

The new apparatus was set up, a machine that almost filled the laboratory ... a giant, compact mass of heavy, solidly built metal work, tied together by beams of girderlike construction. It was meant to stand up under the hammering of unimaginable power, the stress of unknown spatial factors.

Slowly, carefully, Russell Page tapped keys on the control board, setting up an equation. Sucking thoughtfully at his pipe, he checked and rechecked them.

Harry Wilson regarded him through squinted eyes.

"What the hell is going to happen now?" he asked.

"We'll have to wait and see," Russ answered. "We know what we want to happen, what we hope will happen, but we never can be sure. We are working with conditions that are entirely new."

Sitting beside a table littered with papers, staring at the gigantic machine before him, Gregory Manning said slowly: "That thing simply has to adapt itself to spaceship drive. There's everything there that's needed for space propulsion. Unlimited power from a minimum of fuel. Split-second efficiency. Entire independence of any set condition, because the stuff creates its own conditions."

He slowly wagged his head.

"The secret is some place along the line," he declared. "I feel that we must be getting close to it."

Russ walked from the control board to the table, picked up a sheaf of papers and leafed through them. He selected a handful and shook them in his fist.

"I thought I had it here," he said. "My math must have been wrong, some factor that I didn't include in the equation."

"You'll keep finding factors for some time yet," Greg prophesied.

"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.

His hand went out to the power lever, eased it in. With a roar the material energy engine built within the apparatus surged into action, sending a flow of power through the massive leads. The thunder mounted in the room. The laboratory seemed to shudder with the impact.

Wilson, watching intently, cried out, a brief, choked-off cry. A wave of dizziness engulfed him. The walls seemed to be falling in. The room and the machine were blurring. Russ, at the controls, seemed horribly disjointed. Manning was a caricature of a man, a weird, strange figure that moved and gestured in the mad room.

Wilson fought against the dizziness. He tried to take a step and the floor seemed to leap up and meet his outstretched foot, throwing him off balance. His cigarette fell out of his mouth, rolled along the floor.