Accession No

1012

Brief Description

set of drawing instruments in case, by John Rowley, English, 1703

Origin

London; England

Maker

Rowley. John

Class

drawing

Earliest Date

1703

Latest Date

1703

Inscription Date

1703

Material

Shagreen; wood; metal; brass; steel

Dimensions

Sector length 305mm; sector breadth 32mm; scale length 305mm; scale breadth 37mm; compasses radius 254mm

Special Collection

Trinity College collection

Provenance

On loan from Trinity College, University of Cambridge from 1951.

Inscription

I. Rowley Fecit 1703 (sector)
COLLEG TRINIT CANTAB (sector)
I . Rowley Fecit (plain scale)

Description Notes

Half-rounded wooden case with coarse black shagreen covering; divided into six compartments. Push-fit lid. Contains:
12-inch brass sector with two arms joined by flat circular hinge. Obverse has double scales for hords, secants, line of equal parts. Chords scale marked ‘Cho’ divided [0] - 60˚, numbered by 10˚. Secants scale marked ‘Sec’, divided 10˚ - [75˚], numbered by 10˚. Line of lines marked ‘Lin’, divided [0] - 10, numbered by 1. A scale of log numbers is set along the outer edge, becoming a continuous scale when the sector is fully open. It is marked ‘Numbers’ and is divided 1 - 10[0], numbered 1, 2,…9, 1[0], 2[0]…10[0]. Reverse has double scales of tangents and sines. Sines scale marked ‘Sin’ divided [0] - 90˚, numbered by 10˚; first tangent scale marked ‘Tan’, divided [0] - [45˚], numbered by 10˚; second tangent scale marked ‘Tan’, divided 45˚ - 75˚, numbered by 10˚. Scales of log sines and log tangents are on the outer edge, forming continuous scales when the instrument is opened out fully. Log sine scale marked ‘Sins’, divided 2˚ - 90˚, numbered 2, 3…10, 20…90. Log tangent scale marked ‘Tangents’, divided 2˚ - 45˚, numbered 1, 2…9, 10, 20…40, 45.

12-inch brass plain scale, with bevelled edge. Obverse has inch measure scale marked ‘I M’, divided [0] - 12, numbered by 1; decimal foot measure, marked ‘F M’, divided [0] - 100, numbered by 10; scale of chords, marked ‘Chord’, divided [0] - 90˚, numbered by 10˚; scales of equal parts divided [0] - 9 and [0] - 18, numbered by 1, with transversal scales at the ends for division to 10ths numbered 2, 4, 6, 8. Reverse has scales of log tangents, log numbers, log sines, meridional parts, equal parts, chords, rhumbs, longtiudes, sines, secants, latitudes, tangents, hours and half tangents. Scale of log tangents marked ‘T’, divided 1˚ - 45˚, numbered 1, 2, 3…9, 10, 20, 30, 40, 45. Log numbers marked ‘N’, divided 1 - 10[0], numbered 1, 2…9, 1[0], 2[0]…10[0]. Scale of log sines marked ‘S’, divided 1˚ - 90˚, numbered 1, 2,…9, 10, 20…90. Meridional parts marked ‘M’, divided [0] - 80˚, numbered by 10˚. Line of equal parts divided [-10] - [0] - 140, numbered by 10. Line of Chords marked ‘Cho’, divided [0] - 90˚, numbered by 10˚. Line of rhumbs marked ‘R’, divided [0] - 8, numbered by 1. Line of longitudes marked ‘Lon’, divided [0] - 60˚, numbered by 10˚. Second line of equal parts marked ‘EP’, divided [0] - 9, numbered by 1.
Line of sines marked ‘Sin’,divided [0] - 90˚, numbered by 10˚. Line of Secants divided 10˚ - [76˚], numbered by 10˚. Line of latitudes marked ‘Lat’, divided [0] - [90˚], numbered by 10˚. Scale of tangents marked ‘Tan’, divided [0] - [75˚], numbered by 10˚. Line of Hours marked ‘Hours’, divided [0] - VI, numbered by I. Line of half-tangents marked ‘HT’ divided [0] - [149˚], numbered by 10˚. Unknown scale divided [0] - 90˚, numbered by 10˚.

Pair of brass and steel compasses. Main body is brass with brass and steel hinge and steel points. One of these is fixed, the other may be removed and substituted by either a brass and steel daisy-wheel dotting pen or a brass pencil holder with steel and brass pen.

Condition good; complete.

References

Events