Uploaded September 2023 | Updated September 2026, 1 week ago

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A K+E Radial Planimeter, from 1920s. It measures the average radius of a roughly circular shape!

This is episode 76 of my video series about old calculating devices.

Radial planimeter instructions: archive.org/details/radialinstructions

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

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