"An excellent idea," said General French. "It shall be acted upon at once." He turned away, signifying that the interview was at an end.

But Hal had no intention of letting such a piece of work slip through his fingers.

"If you please, general," he said. "Chester and I would like to carry the message. You see, we are greatly interested in this matter."

The general glanced at the two lads, and a faint smile lighted up his face.

"And so you shall," he said at length. "Refresh yourselves with food and drink first, and then report to me."

Hal and Chester saluted and took their departure. Having done as the general ordered, they lost no time in returning to him. General French had already prepared his dispatch and this he placed in Hal's hand.

"General Joffre no doubt will be amazed at the contents of this message," the general told the lads, "and he probably will demand all details from you. Tell them to him as you have to me and I am sure he will be convinced. That is all, except that you return as soon as possible, for I may have other work for you."

The two lads saluted and started forth on their journey. Both had been furnished with good horses at the command of the general, for they had asked for these in preference to being carried in an army automobile.

"Those things are likely to break down any time," Hal had confided to Chester, "and you can always depend upon a good horse."

Chester had agreed with him, so now we find the two lads mounted and riding rapidly toward the southwest, in which direction they knew they should reach the French commander-in-chief.

It was a long, tedious ride, for the French general, that he might have perfect quiet in which to make his plans and direct the movement of the French forces, had made it his custom to remain well in the rear of his army. And here, the following day, the lads found him, and upon informing his orderly that they bore important communications from General French, were admitted to his presence at once.

The French commander-in-chief sat at a small desk, surrounded by members of his staff. Hal and Chester drew themselves up and saluted; then the former advanced and placed the doc.u.ment in Gen. Joffre's hand.

Quickly the French commander ran his eyes over the paper; then leaned back in his chair. For perhaps five minutes he retained this position, uttering no word, apparently deep in thought.

Then he arose, and with a wave of his hand dismissed all his staff, motioning for Hal and Chester to remain. The tent cleared, the general spoke:

"Now tell me your story," he said briefly.

Hal did so, and the general listened attentively, without asking a single question until Hal had concluded his story.

"It must be true," he said at length, half to himself. "I remember well that there was something mysterious in the traitor Dersi's escape. It was never explained satisfactorily. Yes, it must be true."

He was silent again for some moments, then finally spoke again:

"And I would have staked anything I possess on Tromp's honor. He has uncommon ability. Still, there has always been something queer about him. Yes, it must be true."

Suddenly the general sprang to his feet with agility that Hal and Chester had not believed him capable of, and struck a small bell upon his desk a sharp tap. Immediately an orderly entered.

"Have my car brought here instantly," commanded the general briefly.

The orderly saluted and withdrew.

Chester and Hal stared at each other in some surprise. What could the general be about to do? They were soon enlightened.

"I must act at once," said the general, again half to himself. "Never would Tromp have a better chance to work treachery to our cause than at this time. I must stop him, and I must do it personally and without publicity, for should this become noised abroad throughout France, nothing could prove more detrimental to our cause."

He turned suddenly to Hal and Chester.

"And you two shall come with me," he said. "You shall confront Tromp.

If he is guilty, we shall find it out some way."

At that instant the orderly entered again and saluted.

"Your car is ready, sir," he said.

The general moved toward the door, motioning for the lads to follow him.

"Come," he said. "We shall go to the front, where even now Tromp is in command and meditating mischief."

CHAPTER XIX.

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, pa.s.sing 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.