Three-volume alphabetical catalogue of the library formed at Sunderland House, London, by Charles Spencer (1675-1722), 3rd Earl of Sunderland. Entitled Catalogus Bibliothecae Alphabeticus on the spine of each volume. Works are arranged alphabetically by author; volume 1 covers letters A-C, volume 2 D-L, and volume 3 M-Z. For each work the catalogue records the short title, date and place of publication, size and shelf-mark. Manuscript additions and vellum copies are noted. Dated incunables are identified by an asterisk in pencil, undated incunables by a circled asterisk. In one or two cases prices are noted, e.g. Fust and Schffer Bible on vellum, £200.
According to Katherine Swift, this is the earliest extant catalogue of the Sunderland Library, and it is, in fact, an index to the (now missing) inventory catalogue of 1728. This is demonstrated by notes on the rear endpapers, made c 1820 by Vaughan Thomas, librarian at Blenheim, that these volumes are the alphabetical index to the catalogue. The inventory did not appear in the sales of 1881-3. The precise date of the present catalogue is difficult to determine; it may be exactly contemporary with the 1728 inventory, or it may have been produced after the succession of Charles Spencer (1706-1758) in 1729.