Monroe with Electrical Drive
(1922)

This Monroe electro-mechanical calculator was a Christmas present from my good friend Robert Poor.  The calculator belonged to Rob's dad.  Because of the many yeas with no use, it was not working, but Rob and my daughter Marisol disassembled it and fixed it.  It was a wonderful experience to see the inners of the machine and witness the ingenuity of the complex mechanism of these devices.  The machine does not have a model number, but in the back there is a label that says "Superior."  The electrical motor attached to the left has serial number M95613.  This machine was probably built in 1922 and was and adaptation made to the Model K.  Monroe was  one the first companies that used electrical power in their machines.

James Redin Jan, 2004.

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