This calculating device known as 'Napier's box' is a development based on Napier's bones. It allowed multiplication and division to be done by people who knew only addition and subtraction. The device dates from around 1700.
Napier's bones, invented by the Scot John Napier (1550-1617), were individual rods. This device put the bones on cylinders, making it easier to select the correct rods and then keep them in alignment.
A design for placing the bones on cylinders was made within a year of Napier's death by William Schickard, who built an example for the famous astronomer Johannes Kepler. This device was destroyed in a fire the following year. In 1668 Gasper Schott suggested a similar device, and this time it proved very successful. These machines were made throughout the 17th and 18th centuries.
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