sel as long as the journey should
endure. For the atmosphere of Venus is more than twice as dense as ours,
is practically saturated with water-vapor, carries an extremely high
concentration of carbon dioxide, and in their suits and rooms is held
at a temperature of one hundred and ten degrees Fahrenheit. The lenses
of their helmets were of heavy, yellowish-red composition, protecting
their dead-white skins and red eyes from all actinic rays--for the
Venerian lives upon the bottom of an everlasting sea of fog and his
thin epidermis, utterly without pigmentation, burns and blisters as
frightfully at the least exposure to actinic light as does ours at
the touch of a red-hot iron.

Out in space at last, cruising idly with the acceleration set at a point
bearable for the Martians, Westfall called the meeting to order and
outlined the situation facing them. Brandon then handed around folios of
papers, upon which the Venerians turned the invisible infra-red beams of
the illuminators upon their helmets, thus flooding them with the "light"
to which their retinas were most responsive.

"Here's the data," Brandon began. "As you see from Sheet 1, we can
already draw any amount of power we shall need from cosmic radiation
alone...."

"Perpetual motion--ridiculous!" snapped from the sending disk upon the
helmet of the master of mechanism.

"Not at all, Amonar," put in his fellow Venerian, "any more than
a turbo-generator at the foot of a waterfall is perpetual motion.
Those radiations originate we know not where, probably as a result
of intra-atomic reactions. The fields of force of our hosts merely
intercept these radiations, as a water-driven turbine intercepts the
water. We merely use a portion of their energy before permitting
them to go on, to we know not what end. Truly you have made a notable
achievement in science, Tellurian friends, and we congratulate you upon
its accomplishment. Please proceed."

"Upon the following sheets are described the forces employed by the
Jovians, as we shall call them until we find out who or what they really
are. We will discuss these forces later. For each force we have already
calculated a screen, and we have also calculated various other forces of
our own, with which we hope to arm ourselves before we reach Ganymede.
The problems facing us are complex, since there are some nine thousand
forcebands of the order in which we are working, each differing from all
the others as much as torque