The Biblioteca do Palácio Nacional de Mafra has one of the most important Portuguese libraries with a valuable collection of about 30,000 volumes, a true repository of Knowledge. Located on the 4th floor of the monument's east wing, the Library House occupies the most noble and vast of all the building's rooms in the shape of a cross with ca. 85 m long and 9.5 m wide. Paved in lioz stone of different colors, in its centre there is a dome supported by four arches closed over a marble stone where a human face representing the sun is sculpted.
From the library's collection, some rare works are worth mentioning, such as the collection of incunabula (works printed until 1500) or the famous "Chronicle of Nuremberg" (1493), as well as several Bibles or the first Encyclopedia (known as by Diderot et D'Alembert), the illuminated Books of Hours from the 15th century, and also an important nucleus of musical scores by Portuguese and foreign authors, such as Marcos Portugal, J. de Sousa, João José Baldi, among others, written specially for the Basilica's set of six historical organs.
To attest to the importance of this collection, a Bull given by Pope Benedict XIV in 1754 grants the King of Portugal authorization to include in his collection books prohibited by the Index, while also prohibiting under penalty of excommunication the diversion or borrowing of printed or handwritten works without the King's authorization.
For the constitution of his collection, King Magnanimous sent abroad special envoys in charge of acquiring everything best and newest that might be printed there. The Library has a collection whose time span extends from the 15th to the 19th century, covering such different themes as Theology, Sermonary, Canon and Civil Law, History, Geography and Travel, Mathematics, Art and Music, and Medicine, among others. This entire collection is part of the context of improving the press up to the 18th century, an important factor in the development and dissemination of ideas.
The Library's current arrangement began at the end of the 18th century, with the subsequent elaboration of its catalog from 1809 by Frei João de Santa Anna. It is curious to see that after an exhaustive and methodical work by the friar, which resulted in a handwritten catalog in eight volumes, the rules used for its organization are still very up to date - the main entry is made by surname, anonymous works are entered by title, and there is a use of cross-references.
Three of the library's funds - Fundo Mangens; Fundo Moderno; Fundo Possidónio da Silva - are computerized and accessible for consultation.
The bibliographic catalog can be consulted at: http://biblibraries.patrimoniocultural.pt/