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GB2HST comemora 200 anos Shutter Telegraph

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Antonio Matias

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Sep 12, 2012, 4:56:54 AM9/12/12
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The Shutter Telegraph was conceived at the time Napoleon was a threat to Britain and followed
the successful implementation of the system employed by the Chappe Brothers in France. Britain
however, was looking for a less complicated system, cheaper and easier to operate, requiring little
or no training of personnel to run it.

In 1795 following a request from the Admiralty two designs were put forward for consideration , one
from John Gamble which employed five shutters and one from Lord Murray which used six. The
Admiralty chose Murray's design.

Murray's design consisted of a timber building with a twenty foot high frame mounted on the roof.
In this frame were six shutters: two mounted horizontally and three vertically which were pivoted
about their centres. Each shutter was approximately three feet or one metre square and could be
opened and closed using ropes from inside the building. The six shutters gave a total of sixty-three
combinations and these were used to provide letters of the alphabet, numbers and other short
codes.

The Telegraphs were erected in line-of-sight and were five to ten miles apart depending on terrain.
They only operated during the daytime and Dolland telescopes were used to read the signals from
up the line and relayed down the line and vice-versa. The first Telegraph line to be completed was
London to Deal in 1796 and later that year the London to Portsmouth line.

In 1805 the Admiralty wanted communication to its Navy based in Plymouth. A junction was then
formed on the Portsmouth line at Beacon Hill, West Sussex and a line of twenty two Telegraphs were
installed and completed by July 1806.

The stations would have up to five navy personnel at each telegraph: two glassmen (looking through
the telescopes), two to operate the shutters and a lieutenant in overall charge. If the visibility was
bad locally a horse and rider would be dispatched to take the message by hand to the next station
and pass it on. Experiments were made to use some form of lighting at night, but these were the
cause of several fires and not successful.

The Telegraph Stations were kept in operational readiness from 1795 until 1816, when the
telescopes were returned to the Admiralty. They were in actual operation whenever Napoleon was
free and Britain considered itself under threat from invasion. By 1816 the Semaphore Telegraph was
brought in and the line from London to Portsmouth was the first to have the shutters replaced with
the new Semaphore stations.

A new Telegraph line was started towards Plymouth from London which took a different route. This
was achieved only as far as Fordingbridge in Hampshire and was never completed as by then the
costs had soared and Napoleon had been imprisoned on the island of St. Helena. The Semaphore
stations remained until the electric Telegraph became operational in 1847.

 

--
António Matias

CT1FFU - CR5A 


QRV: HF, 6m, 4m,2m,70cm,23cm
SSB, CW, MGM
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