Uploaded September 2023 | Updated September 2026, 2 weeks ago
Manufactured in Japan and sold from the 1950s to the 1970s, the Magic Brain was one of the last popular iterations of the slide calculator or "addiator". Invented in the 17th Century and perfected in the 19th, for over 100 years the addiator was a commonplace tool for performing basic arithmetic, operating on an elegant mechanical implementation of the Method of Complements.
SOURCES
https://americanhistory.si.edu/collections/search/object/nmah_694509
sliderulemuseum.com/Papers/MagicBrainCalculator.pdf
sliderulemuseum.com/Adders.htm
sliderulemuseum.com/Adders.htm#Addiators
http://www.johnwolff.id.au/calculators/addiators/addiators.htm
whipplemuseum.cam.ac.uk/explore-whipple-collections/calculating-devices/pocket-calculating-devices
vintagecalculators.com/html/addiator.html
jaapsch.net/mechcalc/pocket.htm
Manufactured in Japan and sold from the 1950s to the 1970s, the Magic Brain was one of the last popular iterations of the slide calculator or "addiator". Invented in the 17th Century and perfected in the 19th, for over 100 years the addiator was a commonplace tool for performing basic arithmetic, operating on an elegant mechanical implementation of the Method of Complements.
SOURCES
https://americanhistory.si.edu/collections/search/object/nmah_694509
sliderulemuseum.com/Papers/MagicBrainCalculator.pdf
sliderulemuseum.com/Adders.htm
sliderulemuseum.com/Adders.htm#Addiators
http://www.johnwolff.id.au/calculators/addiators/addiators.htm
whipplemuseum.cam.ac.uk/explore-whipple-collections/calculating-devices/pocket-calculating-devices
vintagecalculators.com/html/addiator.html
jaapsch.net/mechcalc/pocket.htm
