You searched for: “arithmometer
Arithmometer (s) (noun), Arithmometers (pl)
A mechanical calculator that could add and subtract directly and perform long multiplications and divisions effectively by using movable accumulators for the results: Patented in France by Thomas de Colmar in 1820 and manufactured from 1851 to 1915, Arithmometers were the first known commercially successful mechanical calculators.

The Arithmometer was a significant contributor to the transformation from human computers to calculating machines that took place during the second half of the 19th century.

When the production of the Arithmometer started in 1851, it launched the mechanical calculator industry which built millions of machines well into the 1970s.

For almost forty years, from 1851 to 1887, the Arithmometer was the only type of mechanical calculator in commercial production which was sold all over the world.

—Compiled from information located at Wikipedia, the free enchclopedia.
This entry is located in the following unit: arithmo-, arith- (page 1)