n power drive was located in the inertial center of the
ship, or as near as the great space coil would permit.

The smaller power units for vertical lift, and for steering, were in the
side walls, hidden under heavy walls of relux.

"The projectors for throwing molecular and heat rays are on the outside
of course. Both of these projectors are protected. The walls of the ship
are made of an outer wall of heavy lux metal, a vacuum between, and an
inner wall of heavy relux. The lux is stronger than relux, and is
therefore used for an outer shell. The inner shell of relux will reflect
any dangerous rays and serve to hold the heat in the ship, since a
perfect reflector is a perfect non-radiator. The vacuum wall is to
protect the occupants of the ship against any undue heat. If we should
get within the atmosphere of a sun, it would be disastrous if the
physical conduction of heat were permitted, for though the relux will
turn out any radiated heat, it is a conductor of heat, and we would
roast almost instantly. These artificial metals are both absolutely
infusible and non-volatile. The ship has actually been in the limb of a
star tremendously hotter than your sun or mine.

"Now you see why it is we need not fear a collision with a small sun,
meteor or such like. Since we are in our own, artificial space, we are
alone, and there is nothing in space to run into. But, if we enter a
huge sun, the terrific gravitational field of the mass of matter would
be enough to pull the energy of our coil away from us. That actually
happened the time we made our first intergalactic exploration. But it is
almost impossible to fall into a large star--they are too brilliant. We
won't be worrying about it," grinned Morey.

"But how did the ship we captured operate?" asked Zezdon Afthen.

"It was a very ingenious system, very closely related to ours, really.

"We distort space and change the velocity characteristics; in other
words, we distort the rate of motion through distance characteristics of
normal space. The Thessian ships work on the principle of distorting the
rate of progress through time instead of through space.

"_Velocity_ is really 'units of travel through space per unit of travel
through time.' Now if we make the time unit twice as great, and the
units traveled through space are not changed, the _velocity_ is twice as
great. That is, if we are moving five light years per second, make the
second twice as long and we are moving