omic bombs can destroy those forts,
and we can move on!" But suddenly the animation and strength left his
voice. He turned a sad, downcast face to his friend. "But Merth Skahl,
we can't do it," he complained.

"Ah--now I can see why you so want to continue this wearing and worrying
work. You need time, Gresth Gkae, only time for success. Tomorrow it may
be that you will see the first hint that will lead you to success."

"Ah--I only hope it, Merth Skahl, I only hope it."

But it was the next day that they saw the first glimpse of the secret,
and saw the path that might lead to hope and success. In a week they
were sending electric bombs across the laboratory. And in three days
more, a magnetic bomb streaked dully across the laboratory to a magnetic
shield they had set up, and buried itself in it, to explode in brilliant
light and heat.

From that day Gresth Gkae began to mend. In the three weeks that were
needed to build the apparatus into ships, he regained strength so that
when the first flight of five interstellar ships rose from Jupiter, he
was on the flagship.

To Phobos they went first, to the little inner satellite of Mars,
scarcely eight miles in diameter, a tiny bit of broken metal and rock,
utterly airless, but scarcely more than 3700 miles from the surface of
Mars below. The Mars Center and Deenmor forts were wasting no power
raying a ship at that distance. They could, of course, have damaged it,
but not severely enough to make up for the loss of their strictly
limited power. The photocells had been working overtime, every minute of
available light had been used, and still scarcely 2100 tons of charged
mercury remained in the tanks of Mars Center and 1950 in the tanks at
Deenmor.

The flight of five ships settled comfortably upon Phobos, while the
three relieved of duty started back to Jupiter. Immediately work was
begun on the attack. The ships were first landed on the near side, while
the apparatus of the projectors was unloaded, then the great ships moved
around to the far side. Phobos of course rotated with one face fixed
irrevocably toward Mars itself, the other always to the cold of space.
Great power leads trailed beneath the ships, and to the dark side. Then
there were huge water lines for cooling. On this almost weightless
world, where the great ships weighing hundreds of thousands of tons on a
planet, weighed so little they were frequently moved about by a single
man, the laying of five miles