compelled to drive him from the Quai d'Orsay, where, for so many years, he had been to his contemporaries a sort of Olympian in the conduct of her foreign affairs. But even in retirement he remained the most powerful man in France; and now he was back in the cabinet again, a giant among Lilliputians, building up the navy, building up the army, strengthening the forts along the frontier, increasing the efficiency of the artillery, experimenting with air-ships, devoting his days and nights to the study of strategy, the discussion of possibilities, always with the same idea, the same hope! And now, this catastrophe!

As he sat gnawing his nails, the President glanced at him, read his thoughts, and shook his head.

"No, my friend," he said, sadly, "the country is not in danger; or, if it is, the danger is from within, not from without. This is an accident, like all the others."

"You believe so? But it seems to me that we have had more than our share of accidents!"

"So we have," the President agreed. "Let us hope that this will be the last—that it will teach us to guard ourselves, in future, from our own carelessness."

"England, America, Germany," Delcassé went on, speaking half to himself, "these nations, with navies greater than ours, never have such accidents. Small explosions, sometimes, it is true, wrecking a gun or damaging a turret—but never destroying a whole ship! Is it merely because they are never careless?"

"There was the Maine," the President reminded him.

Delcassé's hand went to his moustache to hide the ironic smile upon his lips. In that close-cropped head of his, along with many other such secrets, was that of the cause of the catastrophe in Havana harbour. In all the chancellories of Europe, it was agreed that the Maine had been destroyed by the spontaneous explosion of her own magazines. Four men knew the truth, and Delcassé was one of them. There had been a fifth, but an assassin's bullet killed him.

In an instant Delcassé's face was composed, and his eyes, behind their immense glasses, as inscrutable as ever. The President, so ingenuous and child-like, must never suspect the truth!

"True!" Delcassé agreed. "There was the Maine! I had forgotten that," and he relapsed into thoughtful silence.

Evening came, and still the train rolled southward, past Macon, past Lyons, past Vienne, everywhere greeted by surging crowds. At the latter place, Delcassé arose and, with an almost imperceptible nod to Lépine, entered the last car. The Prefect followed him, and a few minutes later, they were closeted together in a compartment, where, at a word from his superior, Inspector Pigot had joined them.

"And now," began Delcassé, when the door was closed and the train had started again, "tell me what you think of this affair, Lépine."

The little grey man spread his hands wide with a gesture of helplessness.

"At this moment I know no more than you, sir," he answered; "probably not so much. By morning, I shall have a report ready for you."

"We shall not arrive until after midnight," the Minister pointed out.

"Nevertheless, my report will be ready, sir," said Lépine, quietly. "Between midnight and dawn there are six hours."

Delcassé looked at him. He knew that this little man never made an empty promise.

"Did you go through the papers at the time of the Jena disaster?" he asked.

"I did, sir. I assisted the investigating board."

"You are, then, familiar with the theories in that case?"

"There were four theories," answered Lépine. "The first was that the ship had been blown up by treachery; that is always the first thought! But in the case of the Jena, it was quickly discovered that treachery was impossible, unless it was that of the highest officers, for only they had access to her magazines. That was unthinkable, for all of them had served France for many years. More than half of them were killed. I myself investigated the life of every one of these men, for it was necessary to be absolutely certain—but not a breath could be raised against them."

"And the second theory?"

"That there had been carelessness of some sort. That, too, was disproved, for no one had entered the magazines for many hours previous to the explosion. It is a rule of the service that, except when in use, the keys of all magazines shall be in keeping of the commander, who is responsible for them. At the inquiry, the commander of the Jena testified that the keys had not left his possession during the two days preceding the accident. There had been no occasion to enter the magazines during that time. The Jena, you will remember, was at anchor in Toulon harbour, just as the Liberté was."

Delcassé glanced at his companion keenly.

"Does that fact suggest nothing to you, Lépine?" he asked.

"Nothing, sir," said Lépine firmly. "I have thought of it all day, and I can see in it nothing except coincidence."

"Coincidence! Coincidence! I detest the word—I do not believe in coincidence!" muttered the Minister.

"Nor I," agreed Lépine; "but even less do I believe in vague theories and vague suspicions. We must have a firm foundation before we begin to build."

"Well, and the third theory?" said Delcassé, at last.

"The third theory was most interesting. It was that the explosion had been caused by waves from the wireless telegraph. It was asserted that these waves had upset the unstable equilibrium, either chemical or electrical, which sometimes exists in the components of modern powder, and that the explosion had resulted."

"And this theory also was disproved?"

"The most exhaustive tests failed to confirm it."

"Ah," said Delcassé; "but to fail to confirm a thing is not to disprove it."

"Our wireless experts agreed in pronouncing the theory absurd."

"Wireless waves penetrate metal, do they not?"

"Every metal except lead."

Delcassé turned this over for some moments in his mind.

"If that had been the cause," went on Lépine, at last, "there would have been other explosions, many of them—and our navy would not have been the only one to suffer. The whole atmosphere is charged with such waves, of every length and every degree of intensity."

"Perhaps you are right," agreed the Minister. "What was the fourth theory?"

"The fourth theory was that finally adopted by the board. It was that a certain kind of powder, known as 'B' powder, degenerates under heat, and becomes, in time, extremely combustible, so that it will sometimes explode apparently without any exciting cause."

"In what manner was the truth of this theory demonstrated?" demanded Delcassé.

"In a most convincing manner. A certain amount of this powder, which the board was examining, did explode in this way, under their very hands. Had the amount been larger, not a member of the board would have escaped. But, sir, you know all this as well as I."

"I wish to refresh my memory," Delcassé explained. "I wish to see if your memory, which I admire so much, agrees with mine. Now tell me this: what was done to prevent a recurrence of such an accident?"

"The powder in all French magazines was overhauled, and that which there was any reason to suspect was destroyed. To prevent future deterioration, the magazines of all our battleships were equipped with a special cooling apparatus. In this, we were soon followed by all other nations."

"And yet," said Delcassé, in a low voice, "the latest and best of our battleships blew up this morning!"

"I have brought my best men with me, as you suggested, sir,"