This article explores questions raised by the evolution of Samuel Johnson's Prefaces Biographical and Critical into the four-volume large 8° The Lives of the Most Eminent English Poets (1781, revised 1783). Examining the texts as printed and placing the work in the context of Nichols's print shop, it argues that, had the prefaces appeared as Johnson conceived and wrote them, they would have constituted a 'modern' history of letters as described by Francis Bacon in De augmentis et dignitatis scientiarum. To that end, the article examines evidence for the collaborative role of John Nichols, the possible effects of John Bell's rival edition on the booksellers' decision to publish with Johnson's work less than half complete, and how that decision affected prefaces written in 1780-1, as well as the kinds of changes required to produce the 'freestanding' four-volume edition of 1781. © Oxford University Press 1998.