Accession No

6711

Brief Description

'Henderson Dial' mining theodolite, by J. T. Letcher, English, late 19th Century

Origin

England; Cornwall; Truro

Maker

J. T. Letcher

Class

surveying

Earliest Date

1869

Latest Date

1899

Inscription Date

Material

metal (brass, iron?); hide (leather); wood (mahogany, other); cloth (felt); paper; glass; liquid (alcohol)

Dimensions

340mm (width) x 340mm (depth) x 168mm (height) [case 1, closed]; 285mm (width) x 240mm (depth) x 200mm (height) [case 2, partially closed]

Special Collection

Provenance

Purchased from Mike Read Antique Sciences in 11/2019.

Inscription

No. 6095 12.6.1916
REPAIRED AND ADJUSTED BY
W. F. STANLEY & CO.
GREAT TURNSTILE, HOLBORN, LONDON
[Paper label stuck inside box lid of case 1]

J. T. LETCHER
WHOLESALE AND RETAIL
SCIENTIFIC INSTRUMENT MAKER,
TRURO,
CORNWALL, ENGLAND
[Paper label stuck inside box lid of case 1]

SPECIALITES: Society of Arts Blowpipe Apparatus & Letcher's Improved Theodolite.
AWARDED—
In International Competition—The SILVER MEDAL and Prize of the Society of Arts.
SILVER & BRONZE MEDALS of the Royal Polytechnic Society.
CERTIFICATE OF MERIT—Mining Institute of Cornwell, their Highest Award
MODELS AND SPECIALITES OF ALL KINDS MADE TO ORDER.
[Paper label stuck inside box lid of case 1]

School [illegible] Henry James
[Handwritten in pen inside the box lid of case 1]

V R
PATENT
LEVED
[engraved on case 1 clasp]

HENDERSON, DIAL
Made by
J.T.Letcher
Truro
Cornwall
[on silvered dial of theodolite, along with degrees and N and S marked]

MANUFACTURED & SOLD BY
[Illegible] LETCHER,
(Successor to Letcher [illegible] & Jeffry
TRURO, CORNWALL
PRACTICAL MANUFACTURER OF MATHEMATICAL, PHILOSOPHICAL, OPTICAL, DRAWING AND MINING INSTRUMENTS
AND [illegible] OF
BLOWPIPE APPARATUS
[Paper label stuck inside lid of case 2, torn in places]

Henry James
[Handwritten in pen inside the box lid of case 2]

Description Notes

'Henderson Dial' mining theodolite, by J.T. Letcher, English, late 19th-century

Theodolite and accessories packed in two mahogany boxes inside leather cases. 33 parts.

Case 1:
Brown leather case with straps and handle, with some scraps of newspaper stuck to the case. Mahogany box is brass bound with a brass clasp. It contains the main parts of the theodolite. The 6" silvered dial (with a removable brass lid) has an inner circle of four 90 degree quadrants double verniers reading to two minutes of arc. The outer 360 degree circle reads with needle vernier to one minute of arc. The silvered compass has East and West transposed. The vertical inverted half circle (marked in 10 degree increments) carries an optical telescope with short and long eye pieces. The box also contains five brass points and other assorted brass pieces.

Case 2:
Brown leather case with leather clasp, with some scraps of newspaper stuck to the case. Mahogany box appears to be lockable, but no key is present. It contains three brass, four screw mounts, the candlestick, and four brass points. There is an empty space, which may or may not have contained another part.

Complete.

References

Events