A bit of unwritten history.

So this is how it transpired that Hal and Chester, two American boys, happened to be present at an interview between the commander-in-chief of the French army and General Emil Tromp, an incident that has never been told, and never will find its way into history; an interview between a gallant French officer and another who, were his actions known, would be likened to the greatest of American traitors—­Benedict Arnold.

Hal and Chester followed General Joffre from his tent without a word and entered his car behind him.

“To General Tromp’s command,” said General Joffre briefly.  “Hurry!”

The chauffeur needed no second urging, and a moment later the huge car was literally flying over the ground, passing large bodies of troops moving rapidly forward as though they were stationary.

Hal and Chester found ample time to take an inventory of the general’s car.  It was a huge machine, and besides being fitted up luxuriously was also furnished as an office, that the general might still be at work while he hurried from one part of the field to another when events demanded his immediate presence.  Even now, with treachery threatening, and whirling along at a terrific speed, General Joffre, probably because of habit, fell to work sorting papers, studying maps and other drawings.

For almost two hours the car whirled along at top speed, and at length pulled up in the rear of an immense body of troops, who, even to Hal and Chester, could be seen preparing for an advance.

General Joffre was out of the car before it came to a full stop, and Hal and Chester were at his heels.  An orderly approached.

“My respects to General Tromp, and tell him I desire his presence immediately,” ordered General Joffre.

The orderly saluted and dashed away.  General Joffre paced up and down nervously.  Finally, at the approach of rapid footsteps, he raised his head.  A group of officers were approaching.  One of them advanced right up to the general and saluted, and even as he did so the sound of a bugle rang out, ordering a general advance.

“Sir—­” began the officer, whom the boys instantly knew to be General Tromp.

General Joffre interrupted him with a wave of his hand.

“Why this sudden advance?” he demanded coldly.

General Tromp started back.

“Why, sir,” he explained, “I have word that a large force of the enemy is approaching to give battle.  I am advancing to meet him.”

“Order a halt,” said General Joffre abruptly.

“But, but—­” began General Tromp in some confusion.

“Order a halt, sir!” commanded General Joffre sternly.  “Or,” as he saw that General Tromp still hesitated, “shall I do it myself?”

General Tromp turned and gave the command to one of his staff, who immediately dashed away.  A moment and a bugle rang out, and the great army came to a pause.