o were kindly and decent; I have let the others
prejudice me. But there was one who was my companion--and there was
McGuire, who was kind and who believed. And now you, who will give
your life for a friend and to save humanity!... You shall have it. You
shall have the ship! But I will not go with you. I want nothing of
glory or fame, and I am too old to fight. My remaining years I choose
to spend out here." He pointed where a window of heavy glass showed
the outer world and a grave on a sloping hill.

* * * * *

"But you shall have full instructions. And, for the present, you may
know that it is a continuous explosion that drives the ship. I have
learned to decompose water into its components and split them into
subatomic form. They reunite to give something other than matter. It
is a liquid--liquid energy, though the term is inaccurate--that
separates out in two forms, and a fluid ounce of each is the product
of thousands of tons of water. The potential energy is all there. A
current releases it; the energy components reunite to give matter
again--hydrogen and oxygen gas. Combustion adds to their volume
through heat.

"It is like firing a cannon in there,"--he pointed now to the massive
generator--"a super-cannon of tremendous force and a cannon that fires
continuously. The endless pressure of expansion gives the thrust that
means a constant acceleration of motion out there where gravity is
lost.

"You will note," he added, "that I said 'constant acceleration.' It
means building up to speeds that are enormous."

Blake nodded in half-understanding.

"We will want bigger ships," he mused. "They must mount guns and be
heavy enough to take the recoil. This is only a sample; we must
design, experiment, build them! Can it be done? ... It _must_ be
done!" he concluded and turned to the inventor.

"We don't know much about those devils of the stars, and they may have
means of attack beyond anything we can conceive, but there is just one
way to learn: go up there and find out, and take a licking if we have
to. Now, how about taking me up a mile or so in the air?"

* * * * *

The other smiled in self-deprecation. "I like a good fighter," he
said; "I was never one myself. If I had been I would have accomplished
more. Yes, you shall go up a mile or so in the air--and a thousand
miles beyond." He turned to close the door and seal it fast.

Beside the instrum