The concluding volumes were delayed for various reasons as Gibbon said to Lord Sheffield in July, 1786: "A book takes more time in making than a pudding." In June, 1787, he says: "I am building a great book, which, besides the three stories already exposed to the public eye, will have three stories more before we reach the roof and battlement," and promises that, with the diligence and speed then exerted, he hopes to be able to have the work ready for the press in August, or perhaps July. In an earlier letter he says:
"About a month ago I had a voluntary, and not unpleasing Epistle from Cadell; he informs me that he is going to print a new octavo edition, the former being exhausted, and that the public expect with impatience the conclusion of the excellent work, whose reputation and sale increases every day, etc. I answered him by the return of the post, to inform him of the period and extent of my labours, and to express a reasonable hope that he would set the same value on the three last as he had done on the three former Volumes. Should we conclude in this easy manner a transaction as honourable to the author and bookseller, my way is clear and open before; in pecuniary matters I think I am assured for the rest of my life of never troubling my friends, or being troubled myself; a state to which I aspire, and which I indeed deserve, if not by my management, at least by moderation."
The publishers had allowed Gibbon two thirds of the profits for the first volume, which amounted on the first edition to £490. In a letter written in 1788, to his stepmother, he refers again to his relations with Cadell: "The public, where it costs them nothing, are extravagantly liberal; yet I will allow with Dr. Johnson 'that booksellers in this age are not the worst patrons of literature.'" Allibone tells us that the historians' "profit on the whole is stated to have been £6,000, whilst the booksellers netted the handsome sum of £60,000."
The sixth volume was finished June 27, 1787, and was published with the fourth and fifth in April, 1788. Gibbon says:
"The impression of the fourth volume had consumed three months; our common interest required that we should move with quicker pace, and Mr. Strahan fulfilled his engagement, which few printers could sustain, of delivering every week three thousand copies of nine sheets. The day of publication was, however, delayed, that it might coincide with the fifty-first anniversary of my own birthday: the double festival was celebrated by a cheerful literary dinner at Mr. Cadell's house, and I seemed to blush while they read an elegant compliment from Mr. Haley."
John Hall, historical engraver to George III, and one of the engravers of the plates for Alderman Boydell's collection, executed the portrait of Gibbon, after Sir Joshua Reynolds, which faces the title-page of our first volume. The plate was issued separately in 1780, Cadell having "strenuously urged the curiosity of the public" as a reason for its immediate publication. It was most appropriate to introduce, as he did, the vignettes emblematic of Rome.
Duodecimo.
Collation: Six volumes.