Consists of eleven library accession register log books. The amount of information varies, but they generally provide accession number, accession date, author, title, publisher, publication date, binding type, source of accession, cost, and remarks. These books were the official record of library accessions beginning in 1859, the year following the Society’s founding in 1858. Books 4 through 9 are American Library Association standard accession-books, produced by the Library Bureau, and contain detailed rules for accessioning and lists of abbreviations to be used. Two of the books (6 and 7) overlap in the years covered.