Accession No
2086
Brief Description
compass (Mariner’s, magnetic), by Spencer, Browning and Rust, English, 1800 (c)
Origin
England; London; [111 Minories, City of London]
Maker
Spencer, Browning and Rust
Class
navigation
Earliest Date
1800
Latest Date
1800
Inscription Date
Material
paper (card); metal (brass); glass; wood (oak)
Dimensions
box length 258mm; breadth 244mm; height 142mm
Special Collection
Provenance
Purchased from P. Delehar, London, England, 08/1975.
Inscription
‘Made by SPENCER BROWNING & RUST, London’
Description Notes
Gimbal-mounted dry card compass. Weighted brass bowl and white interior, glazed. Black and white 32-point compass rose, cardinal points marked, except North has a fleur-de-lys. Decorated E. Central brass bearing. Single brass gimbal ring mounted in oak box. 2 square brass retaining nuts. Sliding oak lid.
References
Events
Description
Magnetic compass
The magnetic compass consists of a magnetic needle attached to a compass card, graduated into angular points, and is used for navigation. The first known dry pivoted compass is dated as early as 1269.
The compass indicates the direction of the magnetic pole but there are problems caused by the difference between magnetic and true north (true north being the useful reading). The variation between the two must be calculated in order to obtain an accurate reading. True north was sometimes simply offset from the direction of magnetic north, but this did not allow for geographical variation. For this, charts were needed. The iron used in building ships during 19th century also led to problems because the magnetism of iron affected the compasses on board.
18/10/2002
Created by: Saffron Clackson on 18/10/2002
FM:42756
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