Uploaded May 2023 | Updated September 2026, 2 hours ago

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The Quixsum Fractional Adding Machine is an adding machine for lengths in feet, inches, and fractions of an inch. It was made in 1924. It is very rare as only about 600 were ever made.

Stephen Freeborn has a nice video of it too:
youtu.be/7f4Q-YwIhKw

For more information about this and other machines in my collection, please visit my website:
jaapsch.net/mechcalc

0:00 Introduction
0:12 History
1:19 Adding
4:04 Clearing
5:02 Opening case
5:02 Opening case
5:33 Mechanism
6:57 Rarity
7:57 Outro