It was hot in the control room. Even Lazarus had voluntarily shed his kilt and shucked down to Venus styles. Metal was hot to the touch. On the great stellarium screen an enormous circle of blackness marked where the Sun's disc should have been; the receptors had cut out automatically at such a ridicubus demand.

Lazarus repeated Libby's last words. "'Thirty-seven minutes to perihelion.' We can't take it, Andy. The ship can't take it."

"I know. I never intended us top this close."

"Of course you didn't. Maybe I shouldn't have maneuvered. Maybe we would have missed the mines anyway. Oh, well-" Lazarus squared his shoulders and filed it with the might-have-beens. "It looks to me, son, about time to try out your gadget." He poked a thumb at Libby's uncouth-looking "space drive." "You say that all you have to do is to hook up that one connection?"

"That is what is intended. Attach that one lead to any portion of the mass to be affected. Of course I don't really know that it will work," Libby admitted. "There is no way to test it."

"Suppose it doesn't?'

"There are three possibilities." Libby answered methodically. "In the first place, nothing may happen."

"In which case we fry."

"In the second place, we and the ship may cease to exist as mattei as we know it."

"Dead, you mean. But probably a pleasanter way."

"I suppose so. I don't know what death is. In the third place, if my hypotheses are correct, we will recede from the Sun at a speed just under that of light."

Lazarus eyed the gadget and wiped sweat from his shoulders. "It's getting hotter, Andy. Hook it up-and it has better be good!"

Andy hooked it up.

"Go ahead," urged Lazarus. "Push the button, throw the switch, cut the beam. Make it march."

"I have," Libby insisted. "Look at the Sun."

"Huh? Oh!"

The great circle of blackness which had marked the position of the Sun on the star-speckled stellarium was shrinking rapidly. In a dozen heartbeats it lost half its diameter; twenty seconds later it had dwindled to a quarter of its original width.

"It worked," Lazarus said softly. "Look at it, Slayton! Sign me up as a purple baboon-it worked!"

"I rather thought it would," Libby answered seriously. "It should, you know."

"Hmm- That may be evident to you, Andy. It's not to me. How fast are we going?"

"Relative to what?"

"Uh, relative to the Sun."

"I haven't had opportunity to measure it, but it seems to be just under the speed of light. It can't be greater."

"Why not? Aside from theoretical considerations."

"We still see." Libby pointed at the stellarium bowl.

"Yeah, so we do," Lazarus mused. "Hey! We shouldn't be able to. I ought to doppler out."

Libby looked blank, then smiled. "But it dopplers right back in. Over on that side, toward the Sun, we're seeing by short radiations stretched to visibility. On the opposite side we're picking up something around radio wavelengths dopplered down to light."

"And in between?"

"Quit pulling my leg, Lazarus. I'm sure you can work out relatively vector additions quite as well as I can."

"You work it out," Lazarus said firmly. "I'm just going to sit here and admire it. Eh, Slayton?"

"Yes. Yes indeed."

Libby smiled politely. "We might as well quit wasting mass on the main drive." He sounded the warner, then cut the drive. "Now we can return to normal conditions." He started to disconnect his gadget.

Lazarus said hastily, "Hold it, Andy! We aren't even outside the orbit of Mercury yet. Why put on the brakes?"

'Why, this won't stop us. We have acquired velocity; we will keep it."

Lazarus pulled at his cheek and stared. "Ordinarily I would agree with you. First Law of Motion. But with this pseudospeed I'm not so sure. We got it for nothing and we haven't paid for it-in energy, I mean. You seem to have declared a holiday with respect to inertia; when the holiday is over, won't all that free speed go back where it came from?"

"I don't think so," Libby answered. "Our velocity isn't 'pseudo' anything; it's as real as velocity can be. You are attempting to apply verbal anthropomorphic logic to a field in which it is not pertinent. You would not expect us to be transported instantaneously back to the lower gravitational potential from which we started, would you?"

"Back to where you hooked in your space drive? No, we've moved."

"And we'll keep on moving. Our newly acquired gravitational potential energy of greater height above the Sun is no more real than our present kinetic energy of velocity. They both exist."

Lazarus looked baffled. The expression did not suit him. '~I guess you've got me, Andy. No matter how I slice it, we seemed to have picked up energy from somewhere. But where? When I went to school, they taught me to honor the Flag, vote the straight party ticket, and believe in the law of conservation of energy. Seems like you've violated it. How about it?"

"Don't worry about it," suggested Libby. "The so-called law of conservation of energy was merely a working hypothesis, unproved and unprovable, used to describe gross phenomena. Its terms apply only to the older, dynamic concept of the world. In a plenum conceived as a static grid of relationships, a 'violation' of that 'law' is nothing more startling than a discontinuous function, to be noted and described. That's what I did. I saw a discontinuity in the mathematical model of the aspect of mass-energy called inertia. I applied it. The mathematical model turned out to be similar to the real world. That was the only hazard, really-one never knows that a mathematical model is similar to the real world until you try it."

"Yeah, yeah, sure, you can't tell the taste till you bite it- but, Andy, I still don't see what caused it!" He turned toward Ford. "Do you, Slayton?"

Ford shook his head. "No. I would like to know... but I doubt if I could understand it."

"You and me both. Well, Andy?"

Now Libby looked baffled. ~'But, Lazarus, causality has nothing to do with the real plenum. A fact simply is. Causality is merely an old-fashioned-postulate of a pre-scientific philosophy."

"I guess," Lazarus said slowly, "I'm old-fashioned."

Libby said nothing. He disconnected his apparatus.

The disc of black continued to shrink. When it had shrunk to about one sixth its greatest diameter, it changed suddenly from black to shining white, as the ship's distance from the Sun again was great enough to permit the receptors to manage the load.

Lazarus tried to work out in his head the kinetic energy of the ship-one half the square of the velocity of light (minus a pinch, he corrected) times the mighty tonnage of -the New Frontiers. The answer did not comfort him, whether he called it ergs or apples.