tion, based upon Earthly and
Osnomian experience, I should say that after twelve or thirteen hours
would come the time for us to make the attack."

"That's good enough for me. Fine, Mart, and thanks. You've probably
saved the lives of the party. We will now sleep for eleven or twelve
hours."

"Sleep, Dick! How could you?" Dorothy exclaimed.

CHAPTER V

First Blood

The next twelve hours dragged with terrible slowness. Sleep was
impossible and eating was difficult, even though all knew that they
would have need of the full measure of their strength. Seaton set up
various combinations of switching devices connected to electrical
timers, and spent hours trying, with all his marvelous quickness of
muscular control, to cut shorter and ever shorter the time between the
opening and the closing of the switch. At last he arranged a powerful
electro-magnetic device so that one impulse would both open and close
the switch, with an open period of one one-thousandth of a second. Only
then was he satisfied.

"A thousandth is enough to give us a look around, due to persistence of
vision; and it is short enough so that they won't see it unless they
have a recording observer on us. Even if they still have rays on us,
they can't possibly neutralize our screens in that short an exposure.
All right, gang? We'll take five visiplates and cover the sphere. If any
of you get a glimpse of him, mark the exact spot and outline on the
glass. All set?"

He pressed the button. The stars flashed in the black void for an
instant, then were again shut out.

"Here he is, Dick!" shrieked Margaret. "Right here--he covered almost
half the visiplate!"

She outlined for him, as nearly as she could, the exact position of the
object she had seen, and he calculated rapidly.

"Fine business!" he exulted. "He's within half a mile of us,
three-quarters on--perfect! I thought he'd be so far away that I'd have
to take photographs to locate him. He hasn't a single ray on us, either.
That bird's goose is cooked right now, folks, unless every man on watch
has his hand right on the controls of a generator and can get into
action in less than a tenth of a second! Hang on, gang, I'm going to
step on the gas!"

After making sure that everyone was fastened immovably in their seats he
strapped himself in the pilot's seat, then set the bar toward the
strange vessel and applied fully one-third of its full power. The
_Skylark_, of course, did not move. T