Showing posts with label Longitude Act 1717. Show all posts
Showing posts with label Longitude Act 1717. Show all posts

Sunday 18 March 2012

Ships Clocks - a brief, broad history

We can only marvel at the amazing journeys taken by seafarers of old who predated the inventions of the industrial age. The Polynesians are understood to have regularly made long ocean voyages navigating by stars, winds, currents and possibly even floating organic materials that signified a particular island's proximity.

For all people of the Pacific, the legendary, but none the less completely true, arrival of the Polynesian forebears of the Maoris, from Hawaiiki around year 1400, to Aotearoa - The Land of the Long White Cloud - (later renamed New Zealand), is a magnificent example of these feats.

With the industrial revolution and the rise of particularly, the British Empire, successful command of the seas was primarily dependent on safe navigation. Safe is a relative term here, as the primitive nautical instruments and their concepts of operation using dead reckoning, often proved inadeqate, leading to the loss of many ships. Notable of these was the 1707 Scilly Naval Disaster where the inability to compute one of, or both longitude and lattitude, with sufficient accuracy was cited as the primary cause of this tragic event.

This lead to the Longitude Act of 1717 with it's prize for a marine chronometer with sufficient accuracy to overcome the limitations described. This signalled rise to fame of the then Barrow-on-Humber inventive clockmaker John Harrison who designed and created the first successful "Sea Clock", the forerunner of the modern marine chronometer. As with so many great creators, he was supported by other significant characters; in his case, he was championed by the then Astronomer Royal, Sir Edmund Halley (as in Halley's Comet), who understood Harrison's brilliance while Harrison had difficulty explaining his ideas to others himself, and financially, by the watch and instrument maker George Graham.

What has this to do with us today? Well, like most sea people, we are facinated by this hard-won history and while some of us may be fortunate enough to visit the Royal Observatory Greenwich and see some of the actual Harrison Sea Clocks, we can all get great use and pleasure from modern versions of marine or ships clocks.

Now, we don't have to spend the 30% of the ship's value that was the cost of one of those very early examples. The fine Wempe and widely-respected Plastimo brand and others offer fully functioning and decorative ships clocks, including radio-room and tide clock types, in both traditional and contemporary styles, that will grace either your boat or home. 

The Wempe Regatta with it's Corum-designed code flags (each flag is a recognised code flag number) as hour markers is one of our favourites.
Wempe Bremen II Ships Clock - Arabic Numerals, Radio Room/Silent Sectors - Brass Case
These are all a long way from the events of the 1700's that led, from John Harrison to our digital world, but we all owe a debt of gratitude to him and the great subsequent collective history of ship's clocks that keep accurate time, in navigation.