Until the introduction of OPACs the printed catalog card (and before that the handwritten catalog card and the bound catalog) was a major limitation for the kinds of subject data and subject points that were made available to the user.
Cards were printed in a number of copies and were supplemented with classification codes and subject headings. The card put constrains on how much text could be used to describe the documents, just as economic constrains put limitations on how many cards could be placed in the catalog. For example, the Royal Library in Copenhagen had no entry for book titles.
"Melvil Dewey of the American Library Association were developing the efficient cataloging systems that prevail to this day. Besides inventing the Dewey Decimal System, Dewey instituted the use of the 3" x 5" catalog card, the size of a standard postcard in those days. In an early example of ergonomic engineering, the dimensions had been carefully calculated to facilitate handling. In Japan, the first library cards appeared in 1890. "
"The familiar 3" x 5" library card stemmed from his [Herbert Putnam's] idea of cataloging books as quickly as the Library of Congress received them via copyright deposit or exchange, and then selling the resulting catalog cards at cost to local libraries. Thus the smaller institutions would be spared the trouble and expense of doing the same work themselves when they bought the same book. "
Microcards were card-catalog-sized* opaque white cards with photographically reduced black printing.
*Catalog cards in the U.S. are dimensioned metrically as 75mm x 125mm (approx.3" x 5"), as prescribed by Melvil Dewey, a metric-system enthusiast.
Paul Otlet introduced this standard in Europe.
Coyle, K. (2005). Catalogs, card - and other anachronisms. Journal of Academic Librarianship, 31(1), 60-62.
Riedesel, L. (2002). Remembrance of Catalog Cards Past. NLA Quarterly, 33(4), 17-19. Available: http://www.nebraskalibraries.org/nlaquarterly/2002-4-Riedesel.htm
Last edited: 17-10-2006