new speed
law?"

"Oh, no," said Wade, waving his pipe in a grand gesture of importance.
"Arcot just decided he didn't like that law and made a new one himself."

"Now _wait_ a minute!" said Fuller. "The velocity of light is a property
of space!"

Arcot's bantering smile was gone. "Now you've got it, Fuller. The
velocity of light, just as Einstein said, is a property of space. What
happens if we change space?"

Fuller blinked. "Change space? How?"

Arcot pointed toward a glass of water sitting nearby. "Why do things
look distorted through the water? Because the light rays are bent. Why
are they bent? Because as each wave front moves from air to water, _it
slows down_. The electromagnetic and gravitational fields between those
atoms are strong enough to increase the curvature of the space between
them. Now, what happens if we reverse that effect?"

"Oh," said Fuller softly. "I get it. By changing the curvature of the
space surrounding you, you could get any velocity you wanted. But what
about acceleration? It would take years to reach those velocities at any
acceleration a man could stand."

Arcot shook his head. "Take a look at the glass of water again. What
happens when the light comes _out_ of the water? It speeds up again
_instantaneously_. By changing the space around a spaceship, you
instantaneously change the velocity of the ship to a comparable velocity
in that space. And since every particle is accelerated at the same rate,
you wouldn't feel it, any more than you'd feel the acceleration due to
gravity in free fall."

Fuller nodded slowly. Then, suddenly, a light gleamed in his eyes. "I
suppose you've figured out where you're going to get the energy to power
a ship like that?"

"He has," said Morey. "Uncle Arcot isn't the type to forget a little
detail like that."

"Okay, give," said Fuller.

Arcot grinned and lit up his own pipe, joining Wade in an attempt to
fill the room with impenetrable fog.

"All right," Arcot began, "we needed two things: a tremendous source of
power and a way to store it.

"For the first, ordinary atomic energy wouldn't do. It's not
controllable enough and uranium isn't something we could carry by the
ton. So I began working with high-density currents.

"At the temperature of liquid helium, near absolute zero, lead becomes a
nearly perfect conductor. Back in nineteen twenty, physicists had
succeeded in making a current flow for four hours in a closed circuit.
It was ju