ch, would show some sort of a light. Some fool would take a
chance to get a smoke. But these Germans! They're not men--they're
machines. They'll obey orders that officers wouldn't take the trouble to
give in any other army. We'll have to make sure. Up we go again!"

Frank could not see how going up would make it possible for them to get
the information that coming down hadn't afforded. But he said nothing,
because he had come to feel by this time that when Captain Greene did a
thing he had a perfectly sound reason for his action. Nor was he wrong.
Once more they climbed in a high spiral curve until they were higher
than they had been before. For the first time, Frank now felt a peculiar
ringing in his ears. He mentioned it, and Greene laughed.

"Pressure," he said. "You'll get used to it! Lord, sometimes I've felt
as if my head would burst when I started to climb. But it doesn't last
long. Feel in the seat there beside you, at your left. There ought to be
a big electric torch."

"Here it is! I've got it, sir," said Frank, a moment later.

"All right. Touch the button at the end. Let's see if it lights up
properly."

It did, decidedly, for the result was a blinding glare.

"Pretty powerful, isn't it?" said Greene. "It's used for signalling, you
see. Flash the light, and you can reproduce Morse perfectly. When you're
high up it can be seen a long way, too. Now hold it straight down and
flash it, then give a steady glare. Let us see if we cannot draw
anything."

Frank obeyed, at the same time getting a glimpse of Greene's idea. He
held the torch pointing straight down, and saw the beam of light
shooting straight down. It was not powerful enough, of course, by the
time it reached the treetops, to illuminate them, and so make anything
below visible, but it was certainly strong enough to be observed from
below, he thought. But still there was no movement, and the uncanny
silence and darkness below persisted.

"All right. There's still another chance," said Greene, patiently. He
drew a revolver from his pocket.

"Flash your little light this way. Let me see if it's all right," he
said.

Frank obeyed.

"New fangled automatic--very powerful, and shoots a .44 bullet almost as
far as an old-fashioned rifle," explained Greene. "Very useful if one
runs into another 'plane unexpectedly--and the other fellow happens to
be a German."

A moment later he opened fire, shooting straight downward. He could not
aim, of course