to the prosaic exigencies of space might in process of time throw it out of gear altogether. Space is the librarian's capital enemy, and the more cruel as it turns his own weapons against himself. The more ample the catalogue, the more liberal the expenditure, the more comprehensive the classification, the greater, sooner or later, are the difficulties from lack of space. It is not too early to direct the earnest attention of the public to the question of the accommodation of the national library. The pressure upon its capacity, now merely beginning to be felt, will soon become serious. It cannot from the nature of the case be divided or dispersed; books required by readers must be within reach of the Reading Room, or they might as well be nowhere. If the library does not receive its fair share of the space about to be vacated by the Natural History departments, the consequence will most assuredly be, first some years of confusion and deadlock as regards all new acquisitions, and then a large expenditure, superfluous with better management, upon new buildings, whose space will be mortgaged before they are completed. It does not seem to us very difficult to devise means for economising the existing space to the utmost, and reconciling the interests of all the departments concerned—but we must not be seduced into a disquisition upon architecture.[62:1] Free libraries and public reading-rooms are among the most important departments of library administration in our day, and constitute the most distinct expression of the growing conviction that the librarian is called upon to be a great popular educator. This sentiment has attained its fullest development in the United States, where the great free libraries have taken a most important place among national institutions. Not merely are such cities as Chicago and Cincinnati provided with libraries of which any city might be proud, but the custodians have in many instances gone beyond the strict limits of professional duty by not merely furnishing reading for the people, but instructing the people what to read. "They have tried," says Mr. Axon in the paper cited already, "and with no small measure of success, to lead readers to higher levels of intellectual interest, and to help all students to the fullest acquaintance with the capabilities of the library." There are no more remarkable examples of popular bibliography than the various catalogues and helps published by the Boston Public Library. These sheets, prepared by Mr. Justin Winsor, have been continued at Harvard since the indefatigable editor's removal thither as professor of bibliography. They include lists of the most important books in all departments of literature, with a selection of the notices of the press best adapted to explain their purport. Special bibliographies of great value are frequently interspersed, and when it is considered that the whole is rather a labour of love than of duty on Professor Winsor's