Mitscherlich type goniometer

Augustus Oertling, Berlin
Mitscherlich type goniometer (brass) with adjustable telescope, engraved silvered scale and vernier read-out (scales are divided to 10 arc-minutes, and read to 10 arc-seconds with the verniers) with adjusting wheels and goniometric head.
Observation telescope, with swing in lens, engraved "A", with focussing wheel and internal cross hair. Telescope mount held on a column mounted onto a centring vernier above the main vernier.  Signal telescope engraved "B" with focussing wheel and internal cross hair. The telescope is mounted on a collar that allows for adjustment via 4 screws. The collar is mounted at the end of a column which is then mounted on a vernier.
Brass base. In wooden cabinet. Diameter circle 15 cm. Total height of the instrument 27 cm.
Signed on the circle "N. 956. | Aug. Oertling | in Berlin." Mid 19th century.

private collection
Photographs courtesy of Fleaglass.com