all the Earth. It was just completed, when...." She trailed
off.

* * * * *

Grim frowned. "Very interesting, but what is so terribly important
about it now?"

"You fool," Hilary exploded, "it's as important as hell. Don't you
see? What are the Mercutians' weapons? Sun-tubes, sun-rays from their
fliers, tremendous burning disks that are their space-ships.
Sun--sun--everything they have depends upon the sun. Take away the
sun, and what have they? Nothing but their hideous giant bodies--they
are weaponless. Now do you see?" He fairly shouted at him.

Grim's face lit up heavily; Wat was dancing insanely.

"Get hold of the machine, reverse the process. Make it form clouds,
great big woolly ones. Start a rain that'll make the Deluge look sick;
forty days--a year--and we'll drown them all," Wat cried.

"Exactly," Hilary nodded. "Joan darling, you and Wat get into the
_Vagabond_, and wait for us. Grim and I will take care of the
laboratory."

"What?" Tyler ejaculated. "Leave me cooped up when there's a fight on.
I'm coming."

"So am I," Joan was pale but determined.

"Oh, Lord," Hilary groaned. "Listen to me, please," he said patiently.
"Time is precious, and I can't argue. Joan, you would only be a
hindrance. I for one would be thinking more of protecting you than
fighting. As for you, Wat," he turned to the furious bantam, "I'm
sorry, but you'll have to take orders. The _Vagabond_ must be guarded.
If we're cut off, we're through. And there's Joan."

"Well. If you want to put it that way," Wat grumbled.

"I knew you'd be sensible," Hilary said hurriedly, not giving them a
chance to change their minds. "At the slightest alarm, take off. Don't
try to rescue us if we don't return. The Earth cause is more important
than any individual. If you get caught, too, the revolt will be
leaderless; at an end."

The men shook hands gravely. Joan, white-faced, kissed Hilary
passionately. "Be careful, my dear."

* * * * *

Then the two men were gone, moving cautiously down the corridor with
deadened footfalls. Hilary had retrieved his automatic; Grim had his
more modern dynol pistol. The guard had been thrust into a corner,
bound, unnoticed.

The laboratory was on the floor below. They trod carefully down the
inclined ramp connecting all the floors. The corridors, the ramp, were
deserted.

"All out fighting," Hilary whispered. "The revolt must be spreading."