This compass binnacle is made of mahogany with brass fittings, which include two oil lamp holders and two chain boxes (for correcting quadrantal error). The four vertical brass strips on the binnacle give access to the corrector magnets held inside. The government mark - a broad arrow - is also stamped onto the binnacle in various places. A metal label identifies the maker as ‘HENRY HUGHES & SON MARINE OPTICIAN 58, FENCHURCH ST. LONDON’.

The liquid compass inside has a white painted mica compass card with a central float which has two needles mounted beneath. The card is marked in points to quarter points. The maker’s name – ‘HUGHES & SON’ - is also marked on the card. The bowl has an expansion chamber at the bottom and the inside is painted white with a black lubber line painted on the side.

This type of compass and binnacle was developed for commercial shipping. This example was passed to the Admiralty Compass Observatory from the trawler ‘Adda’ in 1936.