staggered and pitched forward heavily. Grim's
dynol bullets whined in their passage, spattered the laboratory with
flying blobs of flesh. They did terrible execution. Hilary's automatic
spat its leaden hail.

But the Mercutians were entrenched now behind tables, machinery,
whatever cover they could find. The beams from half a dozen sun-tubes
slithered across the room, burning flaming paths through the
overheated air, bringing the very walls down about them. It could not
last long. Already Hilary had a nasty burn across one shoulder; there
was a streak of red across Grim's forehead as he hid behind the panel
of the entrance, whipping his pistol around to fire, and ducking back
again. There were too many of the enemy, and overwhelming
reinforcements could be expected any moment. The Earthmen's position
was desperate.

Through it all the great weather machine hummed and crackled; the
tubes were sheets of surging flame. Hilary cursed softly. If only the
Cor had completed his sentence before he died. Hilary would have
chanced a sudden rush forward to reverse it, to bring on a deluge of
rain and clouds, even though it meant certain death. The machine
seemed to gleam at him mockingly; the hum continued with tantalizing
smoothness.

"Look out," Grim's voice came to him sharply. He jerked his head back,
just in time. A ray streaked past his ear like a thunderbolt. The heat
from it scorched his face.

* * * * *

The Mercutians were stealthily crawling nearer, pushing heavy, tables
in front of them as shields. He was almost outflanked now. In another
minute he would be exposed.

Hilary thought rapidly. His position was untenable. He would have to
run for it. A sudden dash to the door might possibly win through. But
the machine! He set his teeth hard. If he could not change the
weather, at least he could destroy the infernal thing, stop its
grinding out perfect sunshine for the Mercutians.

He lifted his weapon. Off to one side a Mercutian arm advanced
cautiously, bringing up a sun-tube. He swung on it and fired. The
sun-tube clattered to the floor and the arm jerked back, accompanied
by a howl of anguish. Hilary smiled grimly, took careful aim at the
metal sphere of the machine. The bullet leaped true for its mark. A
little round hole showed--but nothing happened. The infernal machine
hummed softly as ever.

He cursed, fired again. Another round hole, and that was all. With
increasing vi