On March 29, 1777, the night before Easter, Samuel Johnson wrote an apologetic note in his diary: “I treated with the booksellers on a bargain, but the time was not long.” By custom, Johnson set aside Easter Eve for meditation, weighing up his achievements and failures over the past year; doing any business that day seemed, to his painfully active conscience, a kind of offense against both piety and self-discipline. But at least, he reassured himself, it did not take too much time for him to agree to the proposal that the booksellers had brought him: to write brief prefaces for a new edition of English poets.

The three men who visited Johnson that day were emissaries from a much larger group of London publishers. To produce “Works of the English Poets,” a series of fifty-six volumes that promised to include all the important English poets since the Restoration, no fewer than forty-two booksellers had joined fo ...