cles back to the road. "I can hear the firing."

"Yes, and I think it must be a pretty lively skirmish, too," said Frank.
"Captain Hardy would keep them at it. Listen! The Uhlans must outnumber
them three or four to one. I hope the others get up in time."

A few minutes gave assurance that they had. They heard the firing still
more loudly; then, a few minutes later, the heavier sound of the guns
chimed in. And then there was silence behind them.

"Score one for our side," said Frank. "We know a little more than we did
before, too. I think it's a safe guess that the Germans aren't in this
direction. We can go along without worrying about them."

As he said that they were coasting down a little hill, at the bottom of
which, Henri had said, another road crossed the one on which they were
riding just around a little turn in the road. And as they took that
turn, their feet off the pedals, they almost fell off their wheels in
astonishment. For the transverse road was gray-green with soldiers;
soldiers with spiked helmets, marching south!

A moment later they did fall off their wheels, deliberately, and at a
common impulse, because it was the only way there was of stopping before
they were in the midst of the German infantry. There was just a chance
that they had not been seen and they took it, and fled to the hedge
again, leaving their bicycles behind. There was no time to bother about
such trifles now. The thing to do was to make good their escape, if they
could.

"Whew!" said Frank, whistling. "That was a close shave, if you like!
Where on earth did they come from? And how is it they didn't see the
English cavalry?"

"Perhaps they didn't care, if they did see them," said Henri, wide-eyed
with astonishment. "Look, Frank, there must be thousands of them! Where
can they be going?"

"Where did they come from? That's more to the point!" said Frank, vastly
excited. "I know! They got the railway--that's what they did! They must
have come through Arras. Jove, though, they took a terrible risk, Harry!
Because, no matter how many of them there are, they can't even begin to
compare with the allies in numbers--not around here. But how can they be
here without being seen? What are our aeroplanes doing?"

"I haven't seen one all day--not since we left Amiens, at least," said
Henri. "But I know where they are--flying over the enemy's lines, trying
to locate the guns exactly. That's what they try to do, you know. They
decide just