All this time a long-range artillery duel was in progress, whatever advantage there was resting with the Belgians.  Shot and shell poured into the oncoming solid ranks of the German infantry, cutting great gaps in their ranks; but these quickly filled up again, and the Germans continued their steady advance.

All this Hal and Chester saw, and more.  For they could see, to the left, the successful advance of the enemy, as it moved upon the town of Liege.  In vain the Belgians charged upon the advancing line and poured in shot and shell.  The Germans came on.  To the right the Germans also were pushing slowly, but surely, forward.

“It is terrible! terrible!” said Chester, with a shudder, as he watched men fall right and left.

“Horrible!” agreed Hal.  “But come.  We must move.  It is as Captain Derevaux said.  The Belgians will be unable to hold the town.  They must retire upon the forts; and we had better retire before them.”

The boys descended from their position of vantage and made their way to the nearest fort, which they were allowed to enter upon informing an officer of their connection with the Belgian army, just as the Belgian troops withdrew from their positions in front of the city and fell back upon the forts.

Liege was left at the mercy of the Germans.

For some minutes thereafter there was a lull, as when a great storm dies down, only to begin again with greater fury.  The enemy’s left wing, which was nearest the fort in which the boys had taken refuge, could be seen forming for a charge, while from the fort a rain of lead continued to fall upon them.  Although men were falling on every hand, the Germans formed without the least confusion.

Then came the order for the charge.  From five different points the enemy hurled itself forward upon the fort; nor did the hail of lead stop them.  Closer and closer they approached, the five sections of cavalry drawing nearer together as they did so, so that when they were within striking distance they were almost in solid formation.  In their rear the infantry, supported by field guns, already had formed for an advance.

The Uhlans must be driven back at all hazards, and an order rang out from the Belgian commander.

There sallied forth a body of Belgian cavalry and the few French that remained of the French Lancers who had borne the brunt of the fighting in the battle in which Hal and Chester had distinguished themselves.  In the center of these Hal and Chester recognized Captain Derevaux, his sword flashing aloft.

“He is a grand soldier!” whispered Hal to Chester softly.  “A brave man, indeed.  France may well be proud of him!”

“There can be none better,” answered Chester.  “May he come through the battle safely!”

Now the Belgians and French charged, and the fighting was hand-to-hand, while over the struggling horsemen the guns from the fort poured death into the ranks of the advancing German infantry.