ng fire to a city a mile
away, then mopping up with their green flame-throwers if anyone's
left. They pick our planes out of the sky even when they're flying
without lights. Darkness means nothing to them! It was murder to send
troops in against them, troops wiped out to a man! Artillery--that's
no good either when we don't know how many of the devils there are, or
where they are. There's no profit in shelling the place when the
brutes have gone back underground."

Colonel Culver shot a warning glance from Smithy to the seated
officer. "About a hundred square miles of the finest fruit country on
earth laid waste," he admitted gravely; then sought to turn Smithy
from his rebellious mood:

"What's underground, I wonder? Must be a world of caves. Or perhaps
these mole-men can follow up a mere crack or a fault line and open it
out with their flame-throwers to make a tunnel they can go through."

The plane's captain had caught Culver's glance. "Speak your piece," he
said pleasantly. "Don't stop on my account. There's a lot to what Mr.
Smith says--but you don't know all that's going on."

He had been half turned. Now he swung about in his little swivel
chair, whose base was riveted solidly to the floor and whose safety
belt ends dangled as he turned.

"My orders are to deliver you two gentlemen at San Francisco. But
there's a show scheduled for to-night down south of there--two hundred
planes, big and little, scouts, cruisers, battle planes. They're going
to swarm in over when the enemy makes his first crack. There's a devil
of a storm in the mountains along the route we would usually take. I'm
afraid I'll have to swing off south." He was grinning openly as he
turned back to his desk.

Colonel Culver smiled back. "Attaboy!" he said.

But Smithy's forehead was still wrinkled in scowling lines as he
walked forward to an adjoining room. "Underground," he was thinking.
"We've got to carry the fight to them; got to lick 'em so they'll stay
licked. But Rawson--good old Dean--we're too late to help him. And the
lives of all the devils left in hell can't pay for that."

* * * * *

Smithy had been dozing. The shrill whistle of a high-pitched siren
brought him fully awake in an instant. Culver, too, sprang alertly to
his feet. Both men knew the signal was the call to quarters.

They had spread blankets on the floor of the fire-control room. Culver
immediately folded his into a compact bundle,