In the second edition of Greenwood's “Public Libraries,” 1887, p. 137, there is a description of the Dent Indicator, from which it may be gathered that such an indicator was actually constructed. The inventor, however, is of opinion that his idea never got so far as realization in material form, though there can be hardly any doubt that Mr. Dent's indicator is the first to combine indicating with charging, and that it suggested several succeeding devices. His account of it is interesting, as it mentions the existence of an early form of card indicator which has since been reinvented in various styles. “A certain Mr. Christie, Librarian of the Constitution Hill Branch Library (Birmingham), about 1868, constructed a small rack with cards bearing the titles of a selection of the books in history, science, &c, open to the public, and the presence of one of these tickets in the rack indicated that the book was ‘in.’ If anyone wished to take one of the books thus shown, he lifted the ticket out of the rack (there was no glass in front) and handed it to the attendant who put it in a box till the book came back, and then replaced it almost anywhere in the rack. This gave me an idea that the cumberous system of day‐book, posting‐book, and constant piles of books to be marked off as returned might be done away with, if tickets in a rack representing every number in the library were substituted for book‐entry, &c.” Mr. Dent's improvement upon this idea consisted in the provision of a series of numbered shelves in columns, with spaces between to take the borrowers' cards when the books were out. The back of the borrower's card was to be ruled to allow of numbers and dates being pencilled thereon, and, of course, the presence of a borrower's card under a number indicated a book “ out.”
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Sep 1, 2004
Mark Gevisser 
Open Access