SHELFLIST: a file of bibliographic records arranged by call number, i.e. entries are arranged in the same order as materials on the shelves.
To shelflist an item in an online environment is to ensure that the call number assigned to a particular manifestation of a work (i.e., an "edition") is a) unique and b) maintains the integrity of the file, i.e. the file arrangement follows a predictable order.
One particularly important aspect of file integrity involves collocation (bringing together related items). Collocation is a fundamental principle of bibliographic control, the underlying rationale behind authority work, classification, subject assignments, choice of entry, and so on. In shelflisting, the principle is most evident in the practice of keeping editions and translations together on the shelf, but is not restricted to these. (See, for example, the procedures for handling biography and geographic cutters, and for commentaries)
Note that the principle of collocation is not applied to accession-type numbers such as those used for microfilm, or Beinecke "idiot-numbers."
The focus of this document will be primarily on the shelflisting of LC classification call numbers.
The virtual shelflist. Another reason why the Orbis call number arrangement is not totally consistent is because a number of physically separate shelflists, each having its own file integrity, were merged into a single "virtual" (non-physical) shelflist because of recon and Voyager.
SML catalogers shelflist primarily against the YUL file. This file consists of LC classification call numbers assigned by SML, Beinecke, British Art, and Social Science catalogers. "YUL" was the Yale Union [card] Shelflist maintained by cataloging staff of those libraries. Because SML provides cataloging for a number of school and departmental libraries, YUL locations are not restricted to SML, Beinecke, British Art, and Social Science. Libraries including Arts, Classics, Cross Campus, and Kline Science are all part of the YUL file.
The YUL file does not include the LC classification files of the Divinity Library, the Law Library*, the Medical Library, and the Music Library. In practice this means that LC classification numbers assigned by these libraries do not have to be accounted for in maintaining YUL file integrity; a YUL call number only needs to be "unique" within the YUL file. For example, a call number in the Music Library for a particular title/edition can be the same number assigned to a different title/edition in Cross Campus, but a call number assigned to a particular title/edition in Social Science must be assigned to any copy of that particular title/edition held by Cross Campus.
*Note that Law Library records are not in the Orbis database.
However, the combination of recon and online shelflisting requires some adjustment because all libraries contributing records to Orbis now share the same virtual shelflist; the more consistency we achieve, the easier it will be for everyone to shelflist new numbers. At the same time, we will try to avoid disrupting the integrity of the local shelf arrangement whenever possible.