To the surprise of many, the Library of Congress has not had a separate department for the storage and servicing of rare books during most of its history. Early in the historic tenure of Ainsworth Rand Spofford, Librarian of Congress from 1864 to 1897, a practice developed whereby works considered of great value and significance were housed on the bookshelves located in Mr. Spofford's office. Gradually this collection of rarities came to be known simply as the "office collection." Although now long obsolete, the term "office" can still be seen to this day in the catalog entries of hundreds of works at the Library.