Uploaded May 2025 | Updated September 2026, 2 weeks ago

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Otis King's Patent Calculator, a cylindrical slide rule patented in the 1920s by Otis King. Mine was made in 1968.

This is episode 87 of my video series about old calculating methods.

3D printable Otis King: thingiverse.com/thing:7031870

Otis King instructions: archive.org/details/otisking

Fuller Calculator photos by Wikimedia user Thincat
commons.wikimedia.org/wiki/File:Fuller%27s_calculator.jpg
commons.wikimedia.org/wiki/File:Fuller%27s_calculator_in_case.jpg

Dick Lyon's Otis King website: svpal.org/~dickel/OK/OtisKing.html

End song inspired by "Hotter than a Molotov" by The Coup. youtu.be/X8AW7PmsxAY

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

#otis