At this Guillaume became grave and somewhat pale. And he confessed the truth. “Well, I did for a moment think of it.”

However, Bertheroy went on laughing, as if he regarded this answer as mere repartee, though truth to tell he had felt a slight chill sweep through his hair. “Well, my friend,” he said, “you have done far better in offering the world this marvel, which by the way must have been both a difficult and dangerous matter. So here is a powder which was intended to exterminate people, and which in lieu thereof will now increase their comfort and welfare. In the long run things always end well, as I’m quite tired of saying.”

On beholding such lofty and tolerant good nature, Guillaume felt moved. Bertheroy’s words were true. What had been intended for purposes of destruction served the cause of progress; the subjugated, domesticated volcano became labour, peace and civilisation. Guillaume had even relinquished all idea of his engine of battle and victory; he had found sufficient satisfaction in this last invention of his, which would relieve men of some measure of weariness, and help to reduce their labour to just so much effort as there must always be. In this he detected some little advance towards Justice; at all events it was all that he himself could contribute to the cause. And when on turning towards the window he caught sight of the basilica of the Sacred Heart, he could not explain what insanity had at one moment cone over him, and set him dreaming of idiotic and useless destruction. Some miasmal gust must have swept by, something born of want that scattered germs of anger and vengeance. But how blind it was to think that destruction and murder could ever bear good fruit, ever sow the soil with plenty and happiness! Violence cannot last, and all it does is to rouse man’s feeling of solidarity even among those on whose behalf one kills. The people, the great multitude, rebel against the isolated individual who seeks to wreak justice. No one man can take upon himself the part of the volcano; this is the whole terrestrial crust, the whole multitude which internal fire impels to rise and throw up either an Alpine chain or a better and freer society. And whatever heroism there may be in their madness, however great and contagious may be their thirst for martyrdom, murderers are never anything but murderers, whose deeds simply sow the seeds of horror. And if on the one hand Victor Mathis had avenged Salvat, he had also slain him, so universal had been the cry of reprobation roused by the second crime, which was yet more monstrous and more useless than the first.

Guillaume, laughing in his turn, replied to Bertheroy in words which showed how completely he was cured: “You are right,” he said, “all ends well since all contributes to truth and justice. Unfortunately, thousands of years are sometimes needed for any progress to be accomplished.... However, for my part, I am simply going to put my new explosive on the market, so that those who secure the necessary authorisation may manufacture it and grow rich. Henceforth it belongs to one and all.... And I’ve renounced all idea of revolutionising the world.”

But Bertheroy protested. This great official scientist, this member of the Institute laden with offices and honours, pointed to the little motor, and replied with all the vigour of his seventy years: “But that is revolution, the true, the only revolution. It is with things like that and not with stupid bombs that one revolutionises the world! It is not by destroying, but by creating, that you have just done the work of a revolutionist. And how many times already have I not told you that science alone is the world’s revolutionary force, the only force which, far above all paltry political incidents, the vain agitation of despots, priests, sectarians and ambitious people of all kinds, works for the benefit of those who will come after us, and prepares the triumph of truth, justice and peace.... Ah, my dear child, if you wish to overturn the world by striving to set a little more happiness in it, you have only to remain in your laboratory here, for human happiness can spring only from the furnace of the scientist.”

He spoke perhaps in a somewhat jesting way, but one could feel that he was convinced of it all, that he held everything excepting science in utter contempt. He had not even shown any surprise when Pierre had cast his cassock aside; and on finding him there with his wife and child he had not scrupled to show him as much affection as in the past.

Meantime, however, the motor was travelling hither and thither, making no more noise than a bluebottle buzzing in the sunshine. The whole happy family was gathered about it, still laughing with delight at such a victorious achievement. And all at once little Jean, Monsieur Jean, having finished sucking, turned round, displaying his milk-smeared lips, and perceived the machine, the pretty plaything which walked about by itself. At sight of it, his eyes sparkled, dimples appeared on his plump cheeks, and, stretching out his quivering chubby hands, he raised a crow of delight.

Marie, who was quietly fastening her dress, smiled at his glee and brought him nearer, in order that he might have a better view of the toy. “Ah! my darling, it’s pretty, isn’t it? It moves and it turns, and it’s strong; it’s quite alive, you see.”

The others, standing around, were much amused by the amazed, enraptured expression of the child, who would have liked to touch the machine, perhaps in the hope of understanding it.

“Yes,” resumed Bertheroy, “it’s alive and it’s powerful like the sun, like that great sun shining yonder over Paris, and ripening men and things. And Paris too is a motor, a boiler in which the future is boiling, while we scientists keep the eternal flame burning underneath. Guillaume, my good fellow, you are one of the stokers, one of the artisans of the future, with that little marvel of yours, which will still further extend the influence of our great Paris over the whole world.”