Circular slide rule, c 1870.

Image number: 10328304

Circular slide rule, c 1870.

A circular slide rule made by Apps. A circular slide rule affords a long and therefore accurate logarithmic line in a small amount of space. The potential of circular rules was not really utilized until the Victorian period, when several spiral and helical designs appeared on the market.

Image number:
10328304
Credit:
Science Museum/Science & Society Picture Library
Date taken:
21 October 2003 10:10
Image rights:
Science Museum