French sector, 1751-1774.

Image number: 10328287

French sector, 1751-1774.

A brass sector, made by Canivet, Paris, France. French sectors are less complicated than English versions. They were used for calculations involving proportions of length, area and volume. Sectors are composed of two flat arms hinged together that can be adjusted to form any angle. Each arm is engraved with logarithmic and trigonometrical lines, which radiate from the centre of the hinge.

Image number:
10328287
Credit:
Science Museum/Science & Society Picture Library
Date taken:
21 October 2003 10:09
Image rights:
Science Museum