“What you say,” replied the inventor, “is undoubtedly true; yet I am determined that the name of Lambelle shall go down in history coupled with the most destructive agent the world has ever known, or will know. If the Government of France will build for me a large stone structure as secure as a fortress, I will keep my secret, but will fill that building with bottles like this, and then——”

“I do not see,” said the Minister, “that that would lessen the danger, if the unscrupulous man I speak of once became possessed of the keys; and, besides, the mere fact that such a secret existed would put other inventors upon the track, and some one else less benevolent than yourself would undoubtedly make the discovery. You admitted a moment ago that the chances were a future investigator would succeed in getting the right ingredients together, even without the knowledge that such an explosive existed. See what an incentive it would be to inventors all over the world, if it were known that France had in its possession such a fearful explosive! No Government has ever yet been successful in keeping the secret of either a gun or a gunpowder.”

“There is, of course,” said Lambelle, “much in what you say; but, equally of course, all that you say might have been said to the inventor of gunpowder, for gunpowder in its day was as wonderful as this is now.”

Suddenly the Minister laughed aloud.

“I am talking seriously with you on this subject,” he exclaimed, “as if I really believed in it. Of course, I may say I do nothing of the kind. I think you must have hypnotized me with those calm eyes of yours into crediting your statements for even a few moments.”

“All that I say,” said the inventor quietly, “can be corroborated to- morrow. Make an appointment with me in the country, and if it chances to be a calm and sunny day you will no longer doubt the evidence of your own eyes.”

“Where do you wish the experiment to be made?” asked the Minister.

“It must be in some wild and desolate region, on a hill-top for preference. There should be either trees or old buildings there that we can destroy, otherwise the full effects can hardly be estimated.”

“I have a place in the country,” said the Minister, “which is wild and desolate and unprofitable enough. There are some useless stone buildings, not on a hill-top, but by the edge of a quarry which has been unworked for many years. There is no habitation for several miles around. Would such a spot be suitable?”

“Perfectly so. When would it be convenient for you to go?”