In remarkably pristine condition, this ebony and ivory octant was made by the Spencer Browning & Rust Company, London England. This firm existed from 1784 to 1840, preceded by Spencer Browning from 1778 to 1781, and succeeded by Spencer Browning from 1840 to 1870. Throughout the history of the companies, they specialized in navigational instruments, and were known for the quality and precision of their items, selling them to an international market. This octant measures 13" in radius, and is 16" high. The octant is completely intact, with no losses or chips and has a complete set of lenses and mirrors, as is visible in close up photos. The ivory is all engraved with numerical settings, and has both the initials and complete name. Though there is no box, the octant is in rare, near perfect condition. A prime example of this early form of navigation, this octant would please any collector of nautical instruments.