First edition?
The edition in 3 volumes, London, 1846, quoted in Goedeke's Grundrisz., 3. aufl., IV. bd., 3. abt. (1912) is not found in Lowndes' Manual; K. Breul's bibliography (in Poetry and truth ... rev. translation by M. S. Smith, London, 1908); E. Oswald's Goethe in England and America (Publication of the English Goethe society, no. XI, 1909)
Oxenford's translation was preceded in England by the anonymous (abridged) translation in 2 volumes, London, 1824, and a likewise anonymous translation of books I-III and part of book IV in Blackwood's magazine, v. 46-47, 1839-40. It was followed in 1849 by A. J. W. Morrison's translation of the seven remaining books.
The 2 volumes of the Autobiography, with the Letters from Switzerland and Travels in Italy (v. 2, London, 1849) are listed in Bohn's Catalogue as vols. I-II of Goethe's works, tr. by various hands, in Bohn's standard library.
Oxenford's translation of books I-X is an almost literal reprint of the translation by Parke Godwin and J. H. Hopkins, published in 1846 by Wiley & Putnam, New York. In his "Advertisement" Oxenford says that the "American version" is "not sufficiently faithful," that he found "many successful renderings" in the work of this predecessor (whose name he does not give) and that he engrafted them without hesitation. Parke Godwin in the preface to the 2d edition of his translation (New York, G.P. Putnam, 1850) states that Oxenford "simply appropriated the American edition, superadding to the wrong of the theft the injustice of a false accusation," and that "the 'many successful renderings' ... comprise nearly the whole twenty books; that is, the entire work." cf. also H. S. White, Goethe in America, Goethe jahrbuch v (1884) p. 233.