Reproduction of Catalogue Cards by Photographic Methidos

An enormous development of card catalogues is a characteristic of library science in the United States. Their most obvious advantage is that, without interruption of use, they can be kept up to date more easily than is possible with any other kind of catalogue. On the other hand, they are bulky, are costly in time and material, and must be built up with such detailed care that cataloguing is slow. It was a timely aid that the Library of Congress provided when it began to print and s ell catalogue cards. · This event resulted in standardization of the method of preparing cards for our catalogues by using sets of identical author cards, typing added entries and subject headings on their top margins. It eliminated also, when cards precisely fitting our books are obtainable, the errors and inaccuracies incident to the multiple reproduction of cards on the typewriter. \u27When Library of Congress cards are not available, it left us, however, to prepare, type and retype, revise and revise again, the copies of the author cards which an: used in making a set for each book