A mid 19th century navigators Octant.
Unsigned brass 'T' frame design, trade label inside box for D. Mc GREGOR & Co, LIVERPOOL.
The scale is engraved from -5 degrees to 125 degrees and reading to 100 degrees. The index arm has swinging scale magnifier, the vernier scale reads from 0 to 10 seconds of arc.
Complete with two sighting telescopes, telescope sun filter and mirror adjusting pin, contained within its original mahogany box. Height: 9.75 inches / 25 cm, Radius: 7.5 inches / 19cm.
The Octant preceded the design and development of the Sextant. The Octant was invented by John Hadley and Thomas Godfrey simultaneously in 1731.
The Octant gets its name from the Latin word Octans because it is an eighth of a circle (45 degrees) and can measures angles of up to 90 degrees.
By 1780 the octant had almost completely replaced all previous navigational instruments and was half the size of a Davis Quadrant.
In the early days the instrument frames were made from wood, usually Ebony with Ivory scales, however in the later years of Octant production the frames were made from brass and the scales were either Ivory or silver.
Clipper Maritime Antiques specialises in antique navigation instruments.
We offer a wide selection of top quality antique Sextant’s, Quintant’s and Octant’s, prices range from £300 to over £1000.
Price on request: Please Email us your enquiry or if you would like any help or advice about choosing an antique celestial navigation instrument.
Front side of antique octant.
Close up of antique octant ivory scale.
Exterior of the hardwood octant carrying case / storage box.
Reverse side of the antique octant.