19th Century Vernier Octant by John Todd
Vernier Octant by John Todd, London.c.1850
An eleven inch radius vernier octant by John Todd with ebonised wooden frame with inset bone scale marked from 0 to 100 degrees with inset makers plaque.
Laquered brass index arm, pinhole sights, mirrors and shades contained within a stepped ebonised box with embossed lock plate. C.1850
‘Watchmakers and clockmakers of the world’ by Brian Loomes lists John Todd as working in London from 1780.