Uploaded September 2019 | Updated September 2026, 3 hours ago

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The Numeria mechanical calculators were made by Lagomarsino in Italy. They look very much like the Monroe calculator, and are used in exactly the same way. The internal mechanism however is somewhat different, and in this video I try to show this.

My video about the Monroe calculators:
youtube.com/watch?v=5THRNuD4ymk

For more information on these and other mechanical calculators in my collection, visit my website:
jaapsch.net/mechcalc

0:00 Introduction, History
2:17 How to use them
3:12 Mechanism Monroe L
5:50 Mechanism Numeria
10:12 Model numbers
12:27 Outro