The Library of Congress has recently completed arrangements with the College Library and with five of the larger American Public Libraries, whereby a system of co-operative library catalogueing has been established. Each library may obtain, for about four cents each, printed cards classifying under author and subject, any volume in the Congressional Library, which they may desire to catalogue. In return they are to send to the Congressional Library information of all purchases proposed by them; which enables the former to keep in touch with the work of other libraries and to regulate its own selections for purchase. All these lists are printed, whether or not the books are purchased and the resultant classification is brought into the general scheme of distribution, which not only helps every library receiving or likely to receive these books, but also makes the card catalogue of American collections at Washington complete. In this way a person may be advised not merely upon what literature exists, dealing with a certain subject; but also where the particular books required may be most conveniently found. An investigator failing to find in one of these subscribing libraries a work dealing with his subject of research, may easily ascertain whether it is contained in the National Library by reference to these cards; and may, through the intervention of the local library, obtain the use of it under the system of interlibrary loan.

The College Library now receives proof sheets from the Congressional Library about two or three times a week, for all cards printed there, amounting to about 200 each day. Together with five other libraries it sends to Washington titles of all foreign books ordered, and receives from there cards for catalogueing all the current American books purchased.