Guillaume made a gesture of despair. “Ah!” said he, “they are on the right track at last. That tool must certainly have been dropped by Salvat. He worked at Grandidier’s before he came to me for a few days. And from Grandidier they will learn all that they need to know in order to follow the scent.”

Pierre then remembered that he had heard the Grandidier factory mentioned at Montmartre. Guillaume’s eldest son, Thomas, had served his apprenticeship there, and even worked there occasionally nowadays.

“You told me,” resumed Guillaume, “that during my absence Thomas intended to go back to the factory. It’s in connection with a new motor which he’s planning, and has almost hit upon. If there should be a perquisition there, he may be questioned, and may refuse to answer, in order to guard his secret. So he ought to be warned of this, warned at once!”

Without trying to extract any more precise statement from his brother, Pierre obligingly offered his services. “If you like,” said he, “I will go to see Thomas this afternoon. Perhaps I may come across Monsieur Grandidier himself and learn how far the affair has gone, and what was said at the investigating magistrate’s.”

With a moist glance and an affectionate grasp of the hand, Guillaume at once thanked Pierre: “Yes, yes, brother, go there, it will be good and brave of you.”

“Besides,” continued the priest, “I really wanted to go to Montmartre to-day. I haven’t told you so, but something has been worrying me. If Salvat has fled, he must have left the woman and the child all alone up yonder. On the morning of the day when the explosion took place I saw the poor creatures in such a state of destitution, such misery, that I can’t think of them without a heart-pang. Women and children so often die of hunger when the man is no longer there.”

At this, Guillaume, who had kept Pierre’s hand in his own, pressed it more tightly, and in a trembling voice exclaimed: “Yes, yes, and that will be good and brave too. Go there, brother, go there.”

That house of the Rue des Saules, that horrible home of want and agony, had lingered in Pierre’s memory. To him it was like an embodiment of the whole filthy cloaca, in which the poor of Paris suffer unto death. And on returning thither that afternoon, he found the same slimy mud around it; its yard littered with the same filth, its dark, damp stairways redolent of the same stench of neglect and poverty, as before. In winter time, while the fine central districts of Paris are dried and cleansed, the far-away districts of the poor remain gloomy and miry, beneath the everlasting tramp of the wretched ones who dwell in them.

Remembering the staircase which conducted to Salvat’s lodging, Pierre began to climb it amidst a loud screaming of little children, who suddenly became quiet, letting the house sink into death-like silence once more. Then the thought of Laveuve, who had perished up there like a stray dog, came back to Pierre. And he shuddered when, on the top landing, he knocked at Salvat’s door, and profound silence alone answered him. Not a breath was to be heard.

However, he knocked again, and as nothing stirred he began to think that nobody could be there. Perhaps Salvat had returned to fetch the woman and the child, and perhaps they had followed him to some humble nook abroad. Still this would have astonished him; for the poor seldom quit their homes, but die where they have suffered. So he gave another gentle knock.