By Matin Durrani
In this age of e-mails, satellite navigation and mobile phones, which allows scientists and everyone else of course to communicate pretty much instantly, sending messages around the world by telegram down underwater cables seems very much old hat.
But for the pioneers of cable telegraphy in the 1860s, the ability to communicate globally in seconds was a huge advance over the standard method of giving a handwritten letter to a ship’s captain. There was no guarantee the letter would arrive and, even if it did, it could take months to get a reply.
A network of undersea cables was soon formed, now dubbed the “Victorian internet” by science popularizers. Sending telegrams was a bit of a faff — and very expensive to the average punter — but soon thousands of messages were being sent and received every day by governments, military officials and even journalists.
As I discovered while on holiday in rain-soaked Cornwall last week, for Britain many of these cables arrived at a remote, secluded beach at Porthcurno in Cornwall in the south-west of the country, almost near Land’s End.
Porthcurno soon became established as the centre of international telecommunications for the UK. The first cable, laid in 1870, stretched from Cornwall to Gibraltar, before linking up with other cables that continued to Malta, Alexandria and Aden before finally reaching Bombay in India.
At each site, the signal — weakened as it travelled down copper fibres coated with a natural rubber-like material called gutta percha — would be amplified and sent back along its way.
I haven’t got space to go into all the details of how the technology worked, but if you’re in Cornwall, as I was, you can get a first-rate understanding by visiting the Porthcurno Museum.
Celebrating its 10th birthday this year, it includes fascinating details of how, in the early 1900s, scientists at Porthcurno grew more and more anxious about the work of the future Nobel-prize-winning physicist Guglielmo Marconi, who was experimenting with trans-Atlantic radio-wave transmissions from a nearby station at Poldhu on the Lizard.
Fearing that Marconi’s wireless transmission could put cable companies out of business, they set up a clandestine operation to check out what he was up to.
Of course the snag with wireless transmissions is that they can be intercepted by anyone with a suitable receiver. Cable telegraphy is much more secure.
In the end, firms using the rival technology merged to form Imperial and International Communications Limited, which later rebranded itself as…Cable and Wireless.
So important was the Porthcurno station deemed to be to the fortunes of the British Empire, that during the Second World War it was hidden in a maze of tunnels to protect it from enemy attack.
Sadly submarine telegraphy was eclipsed by telephone cables and later fibre-optics. Porthcurno role as a telegraph station ended in 1970 after exactly a century as a working station. A Cable and Wireless college at the site continued for some years, but it too shut in 1993 and transferred to Coventry.
Thankfully the story of Porthcurno can be relived in the museum. Partly housed in the war-time tunnels, it of course makes a great break from the rain.