For sale, a late Victorian ship’s pelorus by A. Black & Co of Glasgow.
Comprised of brass circular two part case and octagonal base for positioning on a binnacle type stand, with domed lid revealing a large seven and a half inch silvered compass dial or bearing plate on a double gimballed base.
The central column contains a large pointer, normally aligned to the course of the ship. The semi circular divided arc, azmith circle and adjustable double sight give this instrument significantly more flexibility and accuracy to measure bearings relative to the ship’s axis.
The company, A. Black & Co remains somewhat of a mystery but I have found one other example with very similar design characteristics made by D. McGregor & Co of Glasgow & Greenoch circa 1880.
The modern pelorus was invented in the 1850’s by Lieutenant Matthew Curling Friend of The Royal Navy (1792-1871) and Fellow of The Royal Society.