In the Rue Monge by Emma Orczy

The commissariat of police of the English Section was a low, narrow building sandwiched between a couple of taller houses in the narrow, ill-lit Rue Monge. It was not one of the busy commissariats of the city, because, being situated in so poor and squalid a quarter, there was not a great number of bourgeois and aristocrats to be hauled up before the commissary in the course of the day. True that once or twice proscribed aristos ahd been discovered lurking perdu in one of other of the tenement houses where only the poor congregate but, on the whole, the citizen commissary, by name Bossut, had mostly to deal with malefactors, night birds and suchlike, not bad enough to send to the guillotine, and thus obtain commendation for his zeal, or even promotion such as came in the way of colleagues who were able to make successful hauls of suspects and traitors.

Indeed, the citizen commissary felt distinctly depressed on this evening. He had sent a couple of pilferers to gaol, three young ruffians to the whipping-post and arrested a stupid old man named Rollin, who styled himself professor and spent his time playing about with glass tubes and instruments and all sorts of poisonous concoctions. A harmless fool enough, but Bossut happened to catch a rumour that this Rollin had a daughter married to an emigré--a rich man, seemingly, who had lived all these years in luxury in England, the arch-enemy of France. Now a man who had a son-in-law of that type was clearly a traitor himself and Bossut, in ordering the arrest of the Professor, had vague hopes that something out of the common would come of it--a sensational trial, perhaps, that would bring in its train that commendation from his superiors, or even that promotion which was the dream of the obscure commissary.