Accession No

4616

Brief Description

ivory protractor and rule by Troughton, 19th C

Origin

London; England

Maker

Troughton

Class

drawing

Earliest Date

1800

Latest Date

1900

Inscription Date

Material

ivory

Dimensions

length 152mm; breadth 43mm; thickness 3mm

Special Collection

Provenance

Inscription

‘TROUGHTON * LONDON’ (obverse)

Description Notes

rectangular ivory rule with bevelled edges.
Obverse: protractor around edge divided [0] - [180˚] in both directions, numbered by 10˚, subdivided to 1˚. Scale of “CHO” (chords) divided [0] - 90˚, numbered by 10˚, subdivided to 1˚. Scale of 1/4 inches divided [1] - [0] - [1]8, numbered by 1, first section subdivided to 1/48 inch. Scale of 1/2 inches divided [1] - [0] - 8, numbered by 1, first section subdivided to 1/24 inch. Scale of 3/4 inches, divided [1] - [0] - 5, numbered by 1, first section subdivided to 1/16 inch. Scale of inches, marked ‘IN’, divided [1] - [0] - 3, numbered by 1, first section subdivided to 1/12.
Reverse: transversal scale for 1/4 inches and 1/2 inches giving reading to 100 parts. Scales for 30, 35, 40, 45, 50 and 60 parts to the inch, similar to those on obverse.

Condition good/fair (black and pink stains); complete.

References

Events