Margherita Cogni, "La Fornarina," a Venetian baker's wife with whom Lord Byron had an affair from ca. August 1817 to sometime in 1819. In an 1819 letter to John Murray, Byron details an incident in which Cogni, in a violent fit, cut his thumb with a knife, then threw herself in the canal. Cogni was illiterate; her letters to Byron were dictated to a professional scribe.
From the guide to the Margherita Cogni manuscript material : 2 items, 1819, (The New York Public Library. Carl H. Pforzheimer Collection of Shelley and His Circle.)