Traicté des plus belles bibliothèques publiques et particulières published in Paris in 1644 by cleric, bibliophile and historian Louis Jacob de Saint-Charles, was the first detailed history of public and "private" libraries, though it could be argued that none of the institutional libraries about which Jacob wrote were "public" in the modern sense of the term. Jacob's work was far more extensive than that of Justus Lipsius (1602), which focussed primarily on Greek and Roman libraries.
Jacob described about 1000 European libraries, and in some cases his description is the only one available. His account of British libraries covered 60 pages—quite extensive for a French scholar.
(This entry was written on the Oceania Riviera off the coast of Turkey in June 2015.)