Other notable groups are 1,400,000 maps and views; 542,000 engravings and other pictorial reproductions, including the splendid Pennell collections; the law library (404,000 volumes). The social and political sciences are represented by 890,500 volumes, language and literature by 350,000, history by 420,000, and pure science by 265,500. The most recent important development in service is the division of aeronautics, established through a benefaction of $140,000 from the Daniel Guggenheim Fund for Aeronautics, now supplemented by an annual congressional appropriation. Special facilities for serious research include some 50 individual study rooms and (elsewhere) 125 special desks or tables. Interlibrary loans for investigators whose work is likely to advance the boundaries of knowledge are sent far and wide through the United States and some abroad. There is a service for blind readers which last year loaned 42,000 volumes in embossed type to some 3,000 readers in the United States. Printed catalogue cards, numbering 110,000,000, prepared by the Library for its own catalogues, are sold at cost to some 6,300 other libraries, effecting for the subscribers prodigious savings in their cataloguing bills but yielding a revenue to the Treasury of $328,405. Until very recently Congress alone provided the funds to meet all the Library’s expenses, excepting one gift of $20,000 received in 1904. But in 1925 the Library of Congress Trust Fund Board was created by Congress, the Secretary of the Treasury and the Librarian of Congress being ex officio chairman and secretary of the board, respectively. The act authorized the board to receive and invest funds for permanent endowments, and the Librarian to receive gifts of money for immediate disbursement. Already endowments aggregating about $2,000,000 and gift funds of $1,415,000 for immediate expenditure have been received and have yielded an income from 1925 to 1938 of $726,000. These new resources add to the bibliographic apparatus and support a project for developing an archive of American folk song. One endowment yields $4,000 per year for the purchase of recent Hispanic literature and employs a consultant to suggest items for purchase in this particular field. [Illustration: THE DECLARATION OF INDEPENDENCE AND THE CONSTITUTION] Six consultants, men of professional rank and experience, are engaged (without any administrative duties) in advising the maturer users of the Library in their investigations. This unique service is to be found nowhere else in libraries. Notable among gifts are those of John D. Rockefeller, jr.--one of $450,000 for the acquisition in facsimile copies of source material for American history existing in the archives of foreign countries, and another of $250,000 for the development of a great union catalogue of important books in other American libraries. The scheme of classification, covering 5,000 printed pages, has been adopted in 80 large libraries in America and Europe.