The O.J. Adder
Channel: Jaap Scherphuis
Date: 2023-08-20

The O.J. Adder is a simple dial adder for adding British currency. It was made in about 1958-1961. It was invented by Oscar Styles Penn, a man who had quite an interesting life.

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

Picture sources:
  Roadless Traction: http://www.classicmachinery.net/forum/viewtopic.php?t=11586
  Machine gun corps: https://en.wikipedia.org/wiki/Machine_Gun_Corps
  Tank: https://en.wikipedia.org/wiki/Mark_V_tank

Thanks to Stephen Freeborn for Oscar Penn's death notice.
https://www.youtube.com/@stephenfreeborn/videos

0:00 Introduction
0:54 History
3:22 Addition
4:51 Clearing
5:26 Opening the case
5:49 Mechanism
7:00 Outro