Pagination with Arabic numerals on both sides of a page was probably first used in a 1513 edition of Niccolò Perotti’s Cornucopiae. This commentary on Martial’s epigrams offered a wide- ranging commentary on every word that Martial used and was valued as the most sophis-ticated Latin dictionary of its time. But since the words were discussed in the order in which they appeared in Martial’s poems, a powerful alphabetical index was essential. The printer Aldus Manutius of Venice explained the novelty of using page numbers in his index: “a very copious index in which each word that is sought can most easily be found, since each half page throughout the whole work is numbered . . . with arithmetical numbers.”

On leaf numbering in the Middle Ages, see Saenger (1996), 258, 275–76, and Stoneman (1999), 6. Saenger notes nonetheless that printing created the context in which leaf numbering flourished in both print and manuscript.