Sunday, January 30, 2011

The new binnacle at South Coast Antiques & Gallery


A binnacle is a case or box on the deck of a ship, mounted in front of the helmsman in which housed instruments, primarily a compass, although others such as an inclinometer along with period illumination for use at night.  Some binnacles are small housings that can be removed such as for small craft, but others are permanent fixtures, bolted to the deck.  Binnacles go back as far as at least the 18th century and they have gone through a slow metamorphosis over the centuries.



 1942 Lionel/Kelvin&White Co. "Liberty Ship/WW2" Ships Binnacle
at South Coast Antiques & Gallery


 The biggest change came in the 1850s with John Gray’s patent where compasses could be corrected for magnetic deviation from the metal in a ship’s hull.  In the 1880s Lord Kelvin went further by adding two iron balls, on each side of the binnacle for compensation.  Despite folklore, the two iron balls were magnetic compensators, not for lashing the wheel.  After that period there were only refinements to that system and an upgrade to electric lights.

The body of this binnacle is made of teak with several coats of spar varnish.  It was bolted deck down with brass screws and the removable shroud is also made of brass with only a small opening.  The compass itself is on a gimbaled system so the movement of the ship didn’t disrupt compass operation.  The binnacle also features an inclinometer that showed how far over a ship was pitched.



 Brass and copper housing

This binnacle is taken from a liberty ship, made in WWII, one of  2,710 ships completed between 1941 and 1945.  Storms, U-boats and war diminished their numbers, but time has whittled the liberty ship to only two operational examples left of the thousands that plied the seas moving crucial supplies, equipment, and troops to allies.  The surviving liberty ships were put in storage after WWII and they were sold off, refitted, mothballed or scrapped.  Hatches, portholes and binnacles turn up on occasion as relics of liberty ships that survived the war, but didn’t survive the peace.

With the introduction of iron-clad ships the magnetic observed deviations in compasses became more severe. Methods of compensation by arranging iron or magnetic objects near the binnacle were developed. In 1854 a new type of binnacle was patented by John Gray of Liverpool which directly incorporated adjustable correcting magnets on screws or rack and pinions. This was improved again when Lord Kelvin patented in the 1880s another system of compass and which incorporated two compensating magnets. These are colloquially known as 'Kelvin's Balls'.



The compass