In Chapter XV of Book the Second of A Tale of Two Cities, the mender of roads climbs the stairs to the garret where once Dr. Manette had been housed by Ernest DeFarge. There he relates the story of Gaspard, the father of the poor child that was run over by the Marquis d'Evremonde's carriage. Gaspard had grabbed hold of the chain beneath the carriage of the Marquis and traveled with it to the chateau where later that night, he killed the Marquis.
Now, the mender of roads tells DeFarge and the others that Gaspard was captured;his arms tied to his sides, he was led by six soldiers to the prison on a hill where he was locked in a cage yet with his arms bound. Finally, he was brought to the fountain where a gallows is fixed right above the fountain. There he is hanged forty feet high--"and is left hanging, poisoning the water." When he and Madame DeFarge hear this story, Madame Defarge registers "The chateau and all the race" in her knitting, and M. Defarge declares, "Extermination."