must lose one one-thousandth of one per cent of our
total energy, and provision must be made for its dissipation in order to
avoid destruction of the laboratory. These air-gap resistances are the
simplest means of disposing of the wasted power."

"I get you--but say, how about disposing of it when we get the thing in
a ship out in space? We picked up pretty heavy charges in the
_Skylark_--so heavy that I had to hold up several times in the ionized
layer of an atmosphere while they faded--and this outfit will burn up
tons of copper where the old ones used ounces."

"In the projected space-vessel we shall install converters to utilize
all the energy, so that there will be no loss whatever. Since such
converters must be designed and built especially for each installation,
and since they require a high degree of precision, it is not worth while
to construct them for a purely temporary mechanism, such as this one."

* * * * *

The walls of the laboratory were opened, ventilating blowers were built,
and refrigerating coils were set up everywhere, even in the tubular
structure and behind the visiplates. After assuring themselves that
everything combustible had been removed, the two scientists put on under
their helmets, goggles whose protecting lenses could be built up to any
desired thickness. Rovol then threw a switch, and a hemisphere of
flaming golden radiance surrounded the laboratory and extended for miles
upon all sides.

"I get most of the stuff you've pulled so far, but why such a light?"
asked Seaton.

"As a warning. This entire area will be filled with dangerous
frequencies, and that light is a warning for all uninsulated persons to
give our theater of operations a wide berth."

"I see. What next?"

"All that remains to be done is to take our lens-material and go,"
replied Rovol, as he took from a cupboard the largest faidon that Seaton
had ever seen.

"Oh, that's what you're going to use! You know, I've been wondering
about that stuff. I took one back with me to the Earth to experiment on.
I gave it everything I could think of and couldn't touch it. I couldn't
even make it change its temperature. What is it, anyway?"

"It is not matter at all, in the ordinary sense of the word. It is
almost pure crystallized energy. You have, of course, noticed that it
looks transparent, but that it is not. You cannot see into its substance
a millionth of a micron--the illusion of transpa