The manuscript is a set of notes written by De Quincey on the rear endpapers of his copy of Ralph Waldo Emerson’s Essays: First Series, New Edition (Boston: James Munroe, 1847). The volume was presented to De Quincey by Emerson in February 1848, when Emerson was lecturing and visiting in Edinburgh. Emerson wrote an inscription on the front free endpaper: ‘Thomas De Quincey, Esq / With the respects of / R. W. Emerson’. The volume is now in private hands. De Quincey’s notes are published here for the first time.