were skillful in avoiding enemy rays, their ray men
were as accurate in placing theirs. But then, with a target of such vast
size, not so much skill was necessary.

These smaller vessels were the ships of Earth. The people of the dark
star had entered the solar system quite unannounced, except that they
had been seen in passing the orbit of Mars, for a ship had been out
there in space, moving steadily out toward Neptune, and the great
interstellar cruisers, flashing in across space, away from that frigid
planet, had not seen the tiny wanderer. But he had seen those mighty
hulks, and had sent his message of danger out on the ether, warning the
men of Earth. They had relayed it to Venus, and the ships that had gone
there had received an equally warm reception, and were even now finding
their time fully occupied trying to beat off the Interplanetary Patrol.

The battle ended as swiftly as it began, for Taj Lamor, in his machine
high above, saw that they were outclassed, and ordered them to withdraw
at once. Scarcely ten minutes had elapsed, yet they had lost twenty-two
of their giant ships.

The expedition that had gone to Venus reported a similarly active
greeting. It was decided at once that they should proceed cautiously to
the other planets, to determine which were inhabited and which were not,
and to determine the chemical and physical conditions on each.

The ships formed again out in space, on the other side of the sun,
however, and started at once in compact formation for Mercury.

Their observations were completed without further mishap, and they set
out for their distant home, their number depleted by forty-one ships,
for nineteen had fallen on Venus.

I

The Terrestrian and Venerian governments had met in conference, a grim,
businesslike discussion with few wasted words. Obviously, this was to be
a war of science, a war on a scale never before known on either world.
Agreements were immediately drawn up between the two worlds for a
concerted, cooperative effort. A fleet of new and vastly more powerful
ships must be constructed--but first they must have a complete report on
the huge invading craft that had fallen in western Canada, and on Venus,
for they might conceivably make their secrets their own.

They called for the scientists whose work had made possible their
successful resistance of the marauders: Arcot, Morey and Wade. They
found them working in the Arcot Laboratories.

"Wade," called