This image is released under a 
Diamond-frame pattern sextant.
Brass sextant with polished brass diamond-pattern frame and limb, with wooden handle in fitted mahogany keystone case by John James Messer, London, England, 1845-55. Consists of inlaid polished silver 131° scale (-5° to 145°) with 15’ divisions and silver vernier (15”), four index-filter shades (red & green), three horizon filters (orange), scale magnifier on 90mm swivelling arm. Fitted with threaded telescope bracket for sighting telescopes (84mm – erect image & 146mm – inverted image) and sighting tube (83mm).
- Measurements:
-
overall: 237 mm x 265 mm x 112 mm, 1.5kg
- Materials:
- brass (copper, zinc alloy) , silver (metal) , glass , wood (unidentified) and mirror-glass (silvered)
- Object Number:
- 1933-12/1
- type:
- sextant
- Image ©
- The Board of Trustees of the Science Museum
