The Mary Baker Eddy Library is a research library, museum, and repository for the papers of Mary Baker Eddy, the founder of Christian Science.^[1]

The library is located on the Christian Science Center, Massachusetts Avenue, Boston, Massachusetts, and housed in a portion of the 11-story structure originally built for the Christian Science Publishing Society. While the library holds the archive for the letters and manuscripts of Mary Baker Eddy, it contains other exhibits, including the Mapparium, a three-story stained-glass globe that allows visitors to stand inside a globe depicting the world of 1934.

The Publishing Society building is one of several structures on the Christian Science Center. The Center was expanded in the 1970s with a design by Araldo Cossutta, Architect-in-Charge, for I. M. Pei & Partners and Araldo Cossutta, Associated Architects. The building was created of limestone and granite, and designed by a local architect, Chester Lindsay Churchill. It originally housed all publishing-related activities of the Church, including massive printing presses and bindery equipment. Engravings on the exterior include the words Purity and Mercy (facing Massachusetts Avenue), Peace and Faith (facing the Mother Church extension), and Hope and Love (facing Clearway Street), as well as verses from the Bible.

The Mapparium is the main exhibit at the library. It is a three-story, inverted globe consisting of 608 stained-glass panels. Visitors walk through the globe via a thirty-foot glass bridge from which they can stand in the middle of the world. Standing in the center of the bridge, a person can see the entire globe with none of the distortions most maps cause.^[2]

The Mapparium's other notable features were actually completely unintentional: its spherical shape and glass construction create multiple unique acoustic effects. Standing in the center of the globe, directly under the North Star, one can hear their voice in surround sound, as though they were speaking into their own ears. At either end of the bridge, visitors can also whisper from one doorway and be heard perfectly from the opposite side, 30 feet away, in a "whispering gallery" effect.

Since the Mapparium was built in 1935, none of the panels have been updated, although one was replaced after being damaged. Visitors to the Mapparium may notice such historic differences as Africa depicted as a patchwork of colonies and the USSR united as one nation. In 2002, LED lights were installed around the globe and, together with an original composition of words and music, highlight these and other major changes since its creation in 1935.

Since its opening in 2002, the church archives have been open to scholars, and has helped produce works in a variety of fields.^[5] Research & Reference Services is located on the fourth floor of the Library and provides access to original materials that document the life of Mary Baker Eddy, the church that she founded, and more. The collections include letters, manuscripts, organizational records, photographs, artifacts, books, periodicals, audiovisuals, and other materials available for in-depth research.

• The Mary Baker Eddy Library website
• Mary Baker Eddy papers, a project of the Library
• MBELibrary Vimeo Channel
• Seekers and Scholars podcast

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