Accession No

0798

Brief Description

prismatic compass, by Charles Augustus Schmalcalder, English, c. 1820

Origin

England; London; 82 Strand

Maker

Schmalcalder, Charles Augustus

Class

surveying; magnetism

Earliest Date

1810

Latest Date

1826

Inscription Date

Material

metal (brass); paper; glass; rope (string)

Dimensions

length 93mm; breadth 73mm; height 83mm

Special Collection

Robert Whipple collection

Provenance

Purchased by Robert Stewart Whipple from G. Green, London, England, on 13/02/1936.

Inscription

‘Schmalcalder’s
PATENT,
No. 82 Strand
London.’ (on compass card)

Description Notes

Brass compass box and lid. Card fixed to needle. Divided [0] - 360 numbered by 10 subdivided to 1. Locking spring below sighting window and locking clamp for when compass not in use. Prism hinged to fold down when not in use and mounted on sliding plate for adjustment of focus. Vertical back-sight over prism opposite fore-sight window with string, which folds over compass when not in use.

Condition good; complete

References

Events