Difference engine

Difference engine is a calculator that was thought up by Charles Babbage.

Difference Engine Media

The London Science Museum's difference engine, the first one built from Babbage's design. It has the same precision on all columns, except in calculating polynomials, the precision on the higher-order columns could be lower.
Per Georg Scheutz's third difference engine, in the Science Museum, London
Fully operational difference engine at the Computer History Museum in Mountain View, California
The Mountain View machine in action

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