of historical books, documents, and artifacts related to the history of computing, communications, and knowledge dating back to 1605, including original manuscripts by Francis Bacon and Rene Descartes and original copies of Newton's Principia & Opticks and Locke's Essay Concerning Human Understanding. The museum also has a vast collection of early office technologies including mechanical adding machines like the Arithmometer, electromechanical/electronic calculators (Friden, SCM, Monroe, Mathatron, Anita, Cal Tech (calculator), and Wang), telephones, telegraphs, typewriters, cash registers, and several telephone switchboards. It also holds an IBM 409 (relay-based tabulator) and a IBM 604 (vacuum tube calculator), mechanical adding machines, and a variety of slide rules. The museum also has military technology, including a Minuteman 1 Missile Guidance Computer and a Norden bombsight. The museum's collection also includes mechanical, electrical, and electronic toys, an industrial robot, and early consumer robots like Hubot. Additionally, the museum has a replica of the Model K, the first binary adder, built for the museum by its inventor, George R. Stibitz. Also, the ACRM holds many mainframe computers and associated hardware from the 1950s to 1990s including the IBM 1620 Model II, the IBM System/360 Model 20, the Burroughs 205, PDP-8, PDP-8/ and the UNIVAC 1004. Signed artifacts at the ACRM include an original Altair 8800 signed by Ed Roberts and an original Apple I signed and donated by Steve Wozniak. The museum also has an original January 1975 Popular Electronics Magazine announcing the Altair signed by Ed Roberts, Bill Gates, Paul Allen and Monte Davidoff. See also Computer museum References External links American Computer & Robotics Museum website Museums established in 1990 Computer museums in the United States History museums in Montana Museums in Bozeman, Montana 1990 establishments in Montana Science museums in Montana