and weapons. He seemed to
notice every detail: their short, tight-fitting suits of some elastic
material that didn't hamper their movements, and their strange flesh,
which just seemed to escape being transparent. Their eyes were strangely
large, and the black spot of the pupil in their white corneas created an
unnatural effect.

Then abruptly their weapons came up--and Arcot responded with a sudden
flick of his ray, as he flung himself to one side. Simultaneously his
four companions let their beams fly toward the invaders. They glowed
strangely red here, but they were still effective. The six beings were
suddenly gone--but not before they had released their own beams. And
they had taken toll. Lieutenant Wright lay motionless upon the floor.

The Terrestrians scarcely had a chance to notice this, for immediately
there was a terrific rending crash, and clean daylight came pouring in
through a wide opening in the wall of the ship. The five rays had not
stopped on contact with the enemy, but had touched the wall behind them.
An irregular opening now gaped in the smooth metal.

Suddenly there came a second jarring thud, a dull explosion; then a
great sheet of flame filled the hole--a wall of ruddy flame swept
rapidly in. Arcot swung up his ray pistol, pointing it at the mass of
flaming gas. A mighty column of air came through the narrow corridor
from the tube, rushing toward the outside, and taking the flame with it.
A roaring mass of gas hovered outside of the ship.

"Lieutenant," said Arcot, swiftly, "turn your ray on that hole, and keep
it there, blowing that flame outside with it. You'll find you can't put
the fire out, but if you keep it outside the ship, I believe we'll be
reasonably safe." The Patrolman obeyed instantly, relieving Arcot.

Wade and Morey were already bending over the fallen man.

"I'm afraid there's nothing we can do for him," the latter said grimly,
"and every moment here is dangerous. Let's continue our investigation
and carry him back to the ship when we leave." Arcot nodded silently.

Solemnly they turned away from the motionless figure on the floor and
set out on their investigation.

"Arcot," began Morey after a moment, "why is that gas burning like that?
Can't we put it out?"

"Let's get through with this job first," replied Arcot somewhat tersely.
"The discussion comes after."

The bodies of the invaders were gone, so they could not examine them
now. That was a matter for the doctors