y located us with a loop while I was
sending your stuff. Damn! I see what they've got!"

"What?"

"A way of transmitting real power in a radio beam," said the 'copter
man. "You've seen eddy-current stoves. Everybody cooks with 'em
nowadays. A coil with a high-frequency current. You can stick your hand
in it and nothing happens. But you stick an iron pan down in the coil
and it gets hot and cooks things. Hysteresis. The same thing that used
to make transformer-cores get hot. The same thing happens near any beam
transmitter, only you have to measure the heating effect with a
thermo-couple. The iron absorbs the radio waves and gets hot. The chaps
in the Wabbly can probably put ten thousand horsepower in a damned beam.
We can't. But any iron in the way will get hot. It blows up a ship at
once. Your monocycle and your rifle too. Damn!"

He knocked the ash off his cigarette.

"Scientific, those chaps. I'll see if that metal's cool."

Something whined overhead, rising swiftly to a shriek as it descended.
Sergeant Walpole cowered, with his hands to his ears. But it was not an
earth-shaking concussion. It was an explosion, yes, but subtly different
from the rending snap of hexynitrate.

"Gas," said the Sergeant dully, and fumbled for his mask.

"No good," said the 'copter man briefly. "Vesicatory. Smell it? I guess
they've got us. No sag-suits. Not even sag-paste."

The Sergeant lit a match. The flame bent a little from the vertical.

"There's a wind. We got a chance."

"Get going, then," said the 'copter man. "Run upwind."

* * * * *

Sergeant Walpole slid over the side and ran. A hundred yards. Two
hundred. Pine-woods have little undergrowth. He heard the helicopter's
engines start. The ship tried to lift. He redoubled his speed. Presently
he broke out into open ploughed land.

In the starlight he saw a barn, and he raced toward that. Someone else
plunged out of the woods toward him. The helicopter-engine was still
roaring faintly in the distance. Then a thin whine came down from
aloft....

When the echoes of the explosion died away the pilot was grinning
queerly. The helicopter's engine was still.

"I said it could be done! Pack of fat-heads at Headquarters!"

"Huh?"

"Picking up a ship by its spark-plugs, with a loop. They're doing that
up aloft. There's a ship up there, forty thousand feet or so. Maybe half
a dozen ships. Refueling in air, I guess, and working with the thi