How far duplicate volumes should be bought should depend upon demand, and the views of the purchasing powers. There is a real need of more than one copy of almost every standard work, else it will be perpetually out, giving occasion for numerous complaints from those who use the library. It would be a good rule to keep one copy always in, and at the service of readers, of every leading history, standard poet, or popular novel. Then the duplicate copies for circulation may be one or more, as experience and ability to provide may determine. A library which caters to the novel-reading habit as extensively as the New York Mercantile (a subscription library) has to buy fifty to one hundred copies of "Trilby," for example, to keep up with the demand. No such obligation exists for the free public libraries. They, however, often buy half a dozen to a dozen copies of a very popular story, when new, and sell them out after the demand has slackened or died away. The methods of selection and purchase in public libraries are very various. In the Worcester (Mass.) Public Library, the librarian makes a list of desiderata, has it manifolded, and sends a copy to each of the thirteen members of the Board of directors. This list is reported on by the members at the next monthly meeting of the Board, and generally, in the main, approved. Novels and stories are not bought until time has shown of what value they may be. The aim is mainly educational at the Worcester library, very special pains being taken to aid all the pupils and teachers in the public schools, by careful selection, and providing duplicate or more copies of important works. In the Public Library of Cleveland, Ohio, there is appointed out of the governing Board a book-committee of three. To one of these are referred English books wanted, to another French, and to the third German books. This sub-committee approves or amends the Librarian's recommendations, at its discretion; but expensive works are referred to the whole board for determination. In the New York Mercantile Library, which must keep continually up to date in its supply of new books, the announcements in all the morning papers are daily scanned, and books just out secured by immediate order. Many publishers send in books on approval, which are frequently bought. An agent in London is required to send on the day of publication all new books on certain subjects.