It is instructive at the same time, for, as we said just now, history passes through the sewer. St. Bartholomew filters there drop by drop through the paving-stones, and great public assassinations, political and religious butcheries, traverse this subterranean way of civilization, and thrust their corpses into it. For the eye of the dreamer all historical murderers are there, in the hideous gloom, on their knees, with a bit of their winding-sheet for an apron, and mournfully sponging their task. Louis XI. is there with Tristan, Francis I. is there with Duprat, Charles IX. is there with his mother, Richelieu is there with Louis XIII., Louvois is there, Letellier is there, Hubert and Maillard are there, scratching the stones, and trying to efface the trace of their deeds. The brooms of these spectres can be heard under these vaults, and the enormous fetidness of social catastrophes is breathed there. You see in corners red flashes, and a terrible water flows there in which blood-stained hands have been washed. The social observer should enter these shadows, for they form part of his laboratory. Philosophy is the microscope of thought; everything strives to fly from it, but nothing escapes it. Tergiversation is useless, for what side of himself does a man show in tergiversating? His ashamed side. Philosophy pursues evil with its upright glance, and does not allow it to escape into nothingness. It recognizes everything in the effacement of disappearing things, and in the diminution of vanishing things. It reconstructs the purple after the rags, and the woman after the tatters. With the sewer it re-makes the town; with the mud it re-makes manners. It judges from the potsherds whether it were an amphora or an earthenware jar. It recognizes by a nail-mark on a parchment the difference which separates the Jewry of the Juden-gasse from the Jewry of the Ghetto. It finds again in what is left what has been,--the good, the bad, the false, the true, the patch of blood in the palace, the ink-stain of the cavern, the tallow-drop of the brothel, trials undergone, temptations welcome, orgies vomited up, the wrinkle which characters have formed in abasing themselves, the traces of prostitution in the souls whose coarseness rendered them capable of it, and on the jacket of the street-porters of Rome the mark of the nudge of Messalina. CHAPTER III. BRUNESEAU.