First published in Blackwood’s Magazine (Jan. 1845), pp. 117–32. Reprinted in SGG, Speculations, Literary and Philosophic (i). 1859, pp. 71–111. The Prefatory Note to this volume of SGG provides an addendum to the essay. A draft for the opening paragraph was transcribed and published in PW, II, 255–6. No other manuscripts have been located.