Octant Sextant, Marine Instrument, Ebony, Spencer Browning & Rust, English, 18th Century, Navigation, Bone

Antique English marine octant signed Spencer Browning & Rust, London, late 18th century, made of ebony and brass, circa 1790/1820

A beautiful scientific and nautical instrument made of ebony and brass, featuring a graduated arc, a movable alidade, mirrors, optical filters, sighting devices, and a maker’s plate inscribed “Spencer Browning & Rust, London.” This instrument was used to measure the altitude of a celestial body or the sun above the horizon, particularly for maritime navigation and the calculation of latitude. It belongs to the great tradition of onboard instruments used by navigators before the widespread adoption of modern sextants.

Spencer Browning & Rust was a London-based manufacturer renowned for its nautical and scientific instruments, active in the late 18th century and the first half of the 19th century. It is associated with the production of octants, sextants, compasses, telescopes, and navigational instruments intended for sailors, officers, captains, and shipowners.

A beautiful piece for a cabinet of curiosities, maritime history, or a scientific collection. The ebony frame contrasts elegantly with the patinated brass fittings. The antique graduations, optical lenses, mirrors, and small filters give the piece a striking decorative presence. A beautiful piece for collectors of scientific instruments, enthusiasts of early maritime history, and for decorating a library, office, or cabinet of curiosities.

Dimensions:
Approximately 28 cm x 27.5 cm.

Condition:
In good overall condition for an antique instrument. Signs of age, brass oxidation, wear, marks, minor soiling, and discoloration of the mirrors and lenses are visible in the photos. Scientific functionality has not been tested. Sold as an antique collector’s item and decorative piece. See the photographs, which are an integral part of the description.