Uploaded May 2022 | Updated September 2026, 1 week ago

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A simple adding machine designed by A.M. Stephenson, patented in the 1870s.

This is episode 60 of my video series about old calculating devices.

Pascal adder photo by Wikimedia user Rama, licenced CC-BY-SA 3.0 France.

X-ray photography taken from: R. Otnes, “A.M. Stephenson and His Adder,” Journal of the Oughtred Society, vol. 13 #2 (Fall 2004): pp. 55-60. Available online at: sliderules.lovett.com/cookiedev/extendeddisplayarticle.cgi?match=bobotnesxxxjournaloftheoughtredsocietyvol.13,no.2,fall,2004pg55.1.jpg

End song inspired by "Hotter than a Molotov" by The Coup.

Chris Staecker webarea: https://faculty.fairfield.edu/cstaecker

#beard #worstpascalineever