History of Computers and Computing, Calculating tools, Gadgets, Computometer
The Computometer of William George Cordingley
The Englishman William George Cordingley, the author of several books for commerce and stock exchange from the end of 19th and beginning of 20th centuries, was a holder of 2 British patents—№GB190715435 from 24-10-1907 (see the lower patent drawing) and №GB190901751 from 27-05-1909 for a stylus operated adder of Pascalene type, which was manufactured under the name Computometer
The device has 7 digital positions, 5 leftmost are decimal, others are divided according to the English monetary system units from the beginning of the 20th century.
The Computometer of Cordingley patent drawing
The Computometer of Cordingley
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