Antique Ebony Octant by G. Rahtjen, Bremen.
ANTIQUE OCTANT. No.57
A mid 19th century navigators Octant made by G. Rahtjen, Bremen. with applied makers plate.
The Octant’s double ‘T’ shaped frame is constructed from ebony with brass fittings and ivory scales. The arc scale is crisp and clearly engraved, reading from -4 degrees to 108 degrees and further divided into 20 minutes of arc. This Octant can measure angles of up to 87 degrees.
This Octant comes with two telescopes, press on telescope sun filter and mirror adjusting tool. It is also fitted with a hardwood handle and has both index mirror sun shades and horizon mirror sun shades.
This Octant has a braced brass index arm, which is fitted with an ivory Vernier scale engraved from 0 to 20 and reading 1 minute of arc. There is a clamping screw to the reverse side with a fine adjustment tangent screw off to the side.
This Octant has a radius of 9.5 inches / 24cm
Front side of the antique octant with telescopes, eye piece filter and mirror adjusting tool.
A close up of the antique octant showing ivory scale and index arm Vernier.
Exterior of the hardwood octant carrying case / storage box.
Reverse side of the antique octant and accessories.
Front side of the antique octant.
Reverse side of the antique octant.
Close up of the ivory makers plaque.
Close up of the octant's Vernier and tangent screw.
Close up of antique Octant showing detail.
Close up of antique Octant showing detail.