What's on your Workbench for February?

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Here is a bit of background for the interested.




Semaphore towers by Brigade models in 6mm.




Your basic signalling code.

Rob.

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Here is the tower in real life in Surrey.




Rob.

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I just found this article on the tower.

Semaphore Stations.





From the Late 18th Century Surrey formed part of a crucial communication link to London. Consisting of a line of buildings with odd looking structures built on the roofs, we look into one of Surrey’s more unusual buildings.

Origins of the Semaphore Station.

In 1796 the Admiralty authorised the construction of a line of communication stations developed in response to the levered semaphore signalling system developed by the French in 1792. The Shutter Telegraph Stations were little more than temporary hut structures with 20 ft vertical frames set upon the roofs. This contained a system of 6 shutters in two columns which could be moved to provide 64 permutations (Hunt 2017).
The stations were built to provide a fast communication Link between the Admiralty to the Royal Dockyards in Portsmouth and the fleet. This system would be crucial during the French Revolutionary Wars and the following Napoleonic War. Two designs were produced for a visual semaphore system the first machine, by Reverend John Gamble, used five shutters and allowed 32 signals, with the second machine, developed by Reverend Lord George Murray, being of 6 shutters (Hunt 2017). After trials of both systems the Admiralty accepted Murray’s system and construction began.




Architectural Model by George Murray.

© National Maritime Museum, Greenwich, London, Admiralty Collection
The Surrey sites formed the Portsmouth Line and were situated at Netley Heath and Hascombe). With the end of the Napoleonic War the stations were shut down by the Admiralty in 1816. Today the early stations no longer survive.

The New London to Portsmouth Line.





An artist’s impression of the semaphore station on Telegraph Hill in the process of sending a message. Image: Dudley Mallinson.

In 1815 an act of government was passed giving the Admiralty permission to buy land for a more permanent Semaphore Telegraph Line. Following the closure of the Shutter stations in 1816, designs were being accepted for the replacement of the Murray Shutter Stations by the Admiralty. The design chosen was by Rear Admiral Sir Home Riggs Popham. This was based on the French Chappe system but used a simpler two signalling arm system in place of three. An experimental line was built in 1818 from the Admiralty to Chatham, to prove if the new semaphore system would work.

With the success of the experimental line, construction began on the new London to Portsmouth Line, becoming operation in 1822. Following a similar route to the previous stations, a number of fortunately survive today. In Surrey these are situated at Chatley Heath (SHER 502), Pewley Hill (SHER 329), Bannicle Hill (SHER 3504), Coopers Hill (SHER 275) Poyle Hill (SHER 1751), Worplesden Glebe (SHER 1829) and Haste Hill (SHER 3531). The Line stayed in operation until the last signal on the 31^st December 1847, following the introduction of the electronic telegraph making the semaphore stations redundant.

An example of the only complete tall tower station survives at Chatley Heath. In 1989 the tower underwent a complete restoration and includes a fully working signalling mechansim. Today the Surrey Wildlife Trust holds open days at the tower so you can explore this building with a unique history.




Chatley Heath Semaphore Tower signalling shutters Copyright Martin Higgins Surrey County Council

Further Reading.

Hunt B http://www.portsdown-tunnels.org.uk/ancient_sites/telegraph_p1.html Accessed 13/02/2017
http://www.bbc.co.uk/news/magazine-22909590

For more information please visit: http://www.surreywildlifetrust.org/e...day?instance=0
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Rob.