the Belgian cavalry continued its
retreat, being hard pressed by the Germans, who were continually
reinforced. From the rear the firing became heavier, and then there was
heard the sound of a galloping body of horsemen.

"Halt!" cried the Belgian officer in command, and the retreating horsemen
came to a stand.

"About face!" And at the command they wheeled to meet the charge of a
force of Uhlans.

The Germans came on bravely; but, just as they hurled themselves upon
their foe, there came from the Belgian rear a fierce hail of rifle shots.
Reinforcements had arrived.

The Germans halted in their fierce charge, and then drew off, shooting as
they went. At the same instant a regiment of Belgian infantry rushed
forward on the run. They pursued the flying Germans for some distance,
and then turned back.

Then the Belgians resumed their retreat to their own lines.

Hal and Chester bore up bravely during this--their first time--under
fire. Unable to take part in the fighting themselves, being without
weapons, they watched with interest the maneuvers of the officers and the
gallantry with which the Belgian cavalry stood up against what at first
were plainly overwhelming odds.

Once in the Belgian lines the boys breathed easier.

"Well, here we are at last," said Hal. "I guess we will be able to
explain our presence in the woods satisfactorily."

"I hope so," replied Chester.

At this moment the officer who had placed them under arrest approached.

"Come with me," he ordered.

The boys accompanied him to the headquarters of the commanding officer,
where their position was explained to the latter.

He listened quietly to Hal's account of their adventures since leaving
Berlin, and it was plain to both boys that as he listened he became more
and more incredulous.

Hal finished his recital, and for some minutes the general sat silent.
Finally he said:

"You have told me a strange story--one that I find it very hard to
believe. I must have proof. It must be substantiated. You will consider
yourselves prisoners until the matter has been investigated, unless in
the meantime there should be someone here who will vouch for your honesty
and the truth of this remarkable tale."

"I will vouch for it, general," came a voice.

Turning, the boys beheld in the entrance to the general's hut the smiling
face of Captain Raoul Derevaux.

CHAPTER XII.

LIEGE.

Hal and Chester started forward.

"Captain Derevaux!"