octant
Object numberP1201
Titleoctant
Creator Browning & Rust Spencer (maker)
DescriptionOctant by Spencer, Browning & Rust of London. Ebony frame with flat brass index arm. The ivory scale or vernier is graduated every 20 minutes from -2 degrees to +99 degrees 40'. In the center of the ivory degree's scale between 50 and 55 degrees is inscribed in script 'SBR' identifying this instrument as that of Spencer, Browning & Rust. It has a long brass index arm. The top horizon mirror is on an adjustable turntable and can be rotated by by loosening a screw which locks the mirror's position. The lower mirror and peep sight (the latter is missing) are used for taking back sights, and were only fitted to very early octants. The two hole peep sight with 'flap', and moveable three sun shade are both missing, as are the three brass legs. An ivory nameplate on the crossbar is engraved with the name of the maker, 'Spencer, Brown & Rust.' A small blank ivory plate has been inserted into the back of the octant, perhaps originally intended to carry the name or initials of the owner. Circa 1780-1800
Production placeLondon
Production date circa 1780 - circa 1800
Object nameoctant
Materialwood
Dimensions
- bar length: 35.5 cm
radius length: 28.5 cm