Accession No

2923

Brief Description

rule by Crichton Bros. c.1900

Origin

London; England

Maker

Crichton Brothers

Class

calculating

Earliest Date

1900

Latest Date

1900

Inscription Date

Material

ivory

Dimensions

length 304mm; breadth 62mm

Special Collection

Provenance

Purchased from Christie’s, South Kensington, London, England; lot 161, 09/12/1982.

Inscription

‘CRICHTON BROS LONDON’

Description Notes

Ivory rule with bevelled edges, divided [0] - [180] and [180] - [0] round 3 edges. [0] - 34 ( [0] - 42; 10-2-2000) in quarter inches along 4th edge. Table of CHORDS [0] - 90 and division of the inch from 1/8 to 1 1/2. Verso diagonal scale divided [0] - 22 in half inches with diagonals over first and last half inch. Table of divisions of the inch from 1/60 to 1/10.

Condition: fair (crack, one chip); complete.

References

Events

Description
Scale Rule
A straight rule with a scale engraved along the length is the simplest instrument for making linear measurements, and has been used since antiquity. However, scale rules were not commonly used for making scale drawings until around 1550 in Northern Europe. Anthropomorphic dimensions such as the foot were commonly used for the scale.

Scale rules can be straight or folding and often have even scales on one side and diagonal scales on the other, which enable the user to divide any measurement into 100 parts. They were often decorated by the maker, demonstrating artistic as well as mathematical skills (although they became more purely functional from mid 18th century). They were usually made of brass, silver, ivory or boxwood.

FM:42484