Cambridge, cables and Cornwall

The West of England is a very popular destination today: very obviously for holidaymakers, but less so for submarine fibre optic cables.

A holiday in ‘The Cornish Riviera’ – the term coined by the Great Western Railway after it opened its line to Penzance in 1867 – has allowed a visit to the Porthcurno.

Porthcurno was the place that the first global submarine cable was launched to allow communication with the far flung reaches of the British Empire in 1870 – just three years after the Great Western steamed past – and as a result is the spiritual home of today’s Cable & Wireless company.

In 1870 each section of submarine cable had a team of operators sitting at its end, reading the incoming Morse code, and then manually relaying the message to the next section: a task now undertaken by a series of amplifiers laid out along the seabed.

That tenuous link with India was completed on 9 April 1870, and the new submarine cable was initiated with a message consisting of a single word – ‘Cambridge’.

In this way Mumbai (Bombay) knew the winner of that peculiarly English institution, the Oxford – Cambridge Boat Race, which is held each year on the River Thames in London. The result was known within an hour of the finish. Most of the (local) UK population, however, had to wait for the distribution of the newspapers the next day.

In 1869 John Pender had formed his first telegraph company, the Falmouth Gibraltar and Malta, with the aim of completing a chain of cables connecting India to England with cables via Gibraltar and Portugal. The name was misleading, as although Pender intended the cable to land at Falmouth, the final landing point was the more westerly Porthcurno, near Land’s End.

The completion of this cable in 1870 was the final link in the London to Bombay line, and in 1872, this was one of the companies merged to form the Eastern Telegraph Company.

Things have changed since then – but not as much as you might think. The technique for producing armoured cables had emerged only 20 years before. The only really significant difference between the cable landed in 1870 and the ones that now pass up the main street under a series of black manhole covers marked ‘telecom’ is the material in the core: in 1870 it was copper; today it is a strand of glass.

Unmarked manhole covers hide modern fibre optic cables in Porthcurno village at the entrance to the Telegraph museum
But it also seems remarkable that the basic principles of 1870 still hold today. In the Telegraph Museum there is a range of working Victorian telegraph instruments. They consist of a needle pushed first one way and then the other. As the guide will tell you, this is pure binary – a system using zeros and ones to communicate complex messages. And binary today still underpins our global communication system. Simple beginnings indeed.

The village today has a beech, a delightful cove and the famous open-air Minac Theatre. Yet a glance at Telegeography’s 2013 Submarine Cable Map¬†shows one of the world’s largest concentrations of fibre optic cables crowding into the westerly toe of Great Britain. Only a handful of the cables now make it up the narrow main street of Porthcurno. Later cables landed further west, and over on the north coast at Bude.

A performance at the open-air Minac Theatre
The audience watching the drama unfold below them on the stage of the famous open-air Minac Theatre will be totally unaware of the quite communications drama being played out behind the actors, just feet below the sea.
But the vast volume of data that now flows seamlessly through those modern cables seems a very far cry from that single 9-character word which required a significant team of operators to help it along its way.


Keith Wallace

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