in behind them. But now they had a good lead and
were racing on toward the forts, toward the circle of wide swinging
searchlights.

"How are we getting on, Paul?" asked Arthur. "Are we gaining?"

"I'm afraid--no, we're not. They're coming along awfully fast. That
must be a much more powerful machine than this."

"I don't think it's that. I'm awfully afraid that our gasoline is
running low! That German must have ridden a long way. Probably he
expected to fill his tank back there! There's so much noise that I'm
not sure, but I'm afraid one cylinder is missing. That's what is
making us slower."

Over their heads now a bullet sang out sharply. There could be no
doubt about it at all, now; the other motorcycle was rapidly making up
lost ground. Then while they still raced on, and when the other
machine was less than a hundred yards behind, the whole road was paved
in light again, as the Boncelles searchlight swung around and down, and
was focused full on the chase.

Still the other cycle gained, but there were no more shots. The reason
for that was made plain in a few moments by a call to surrender.

"They're only boys!" one of the Germans had yelled to the other. "We
can catch them. Don't let's hurt them."

And then, with the distance between the two machines being reduced
every minute, they could hear one of the Germans shouting to them.

"Stop! Surrender!" he cried. "You can't escape--we're gaining all the
time! If you stop now, you won't be hurt!"

Then the searchlight swung away, and in that same moment Paul had an
inspiration. He remembered that in his pocket was a glass flask that
had contained water. He took this out now, and broke it against the
steel frame of the motorcycle. The fragments cut his fingers, but he
ignored the cuts and the flow of blood. At the risk of hurting himself
still more, he broke the fragments again in his hand. Then he began
dropping the sharp pieces of glass. And in a minute he had his reward.
From behind came two sharp explosions, and looking back, he saw the
other motorcycle swerve and fall. The two riders went sprawling.

"Get all you can out of her, Arthur!" he shouted. "I spilled them.
The glass punctured both their tires! That was luck! It won't stop
them for long, but it's given us a little more time. I don't believe
they'll put on new tires, even if they're carrying them. And if they
don't, it will make them much slower. You can't go so fas