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Wires over the ground

Telegraph poles under bridge, Shropshire Union Canal, 1930s

Keeping the wires up : keeping a delicate balance

Although they are insulated today, wires were originally bare and left open to the elements where they are particularly vulnerable. Wire expands and contracts according to temperature so the lines were always rigged using a thermometer and slide rule - to make sure they never sagged or contracted to dangerous levels in sunny or icy weather.

The bare wires had to be placed on insulators on the pole with enough space between them for the wires not to cross. The wires themselves came in many sizes, thicker for the trunk routes and thinner for local connections.

Home connections were kept loose and were generally safe, but the heavier network wires were kept much more taut and repairs had to be made cautiously. Cutting a wire could cause it to whip back like a wire razor, but equally the release of tension could snap the top of the pole off in the other direction.

Maintenance work on 'H' telegraph pole, 1934

What's in a name? : a matter of opinion

The poles that carry telephone messages around the world are still known as telegraph poles to most people and in a sense that is still exactly what they are. The only difference now is that the telegraph message being carried is a voice communication, in other words a telephone call, rather than a Morse Code message.

That's not to say that the word telephone pole is wrong, in fact both of them are accurate descriptions, it's more a matter of what you're used to. What do you say? Is it the same as your friends and family?

Collapse of iron pole route, in Ditchling Road, Brighton; June 19, 1914

Pole materials : blowing in the wind and keeping upright

Telegraph poles can be dangerous if they snap or break so a variety of materials have been tried to find the safest one. The poles have to carry the tension and weight of the wires, which means there needs to be enough flexibility to cope with the sudden release of a broken wire.

To start with The GPO used wooden and cast iron poles. However, eventually cast iron was rejected as being unsuitable. This was extraordinarily demonstrated in Brighton after a lorry backed into and snapped an iron pole. The release of tension caused a long line of consecutive poles to snap in a domino effect until a wooden one managed to break the chain.

There have also been concrete poles and more recently hollow fibreglass and stainless steel poles, which can be rigged from the ground with the wire raised through the middle. But wood has consistently proved to be the most suitable for the job.

Woodpecker hole in telegraph pole - a Connected Earth artefact, now at Amberley Museum

Telegraph pole : making a nuisance of himself

Telegraph poles are a common sight up and down the length of the country. However, some have encountered some unforeseen hazards.

From a bird's perspective they look like trees and one particular pole caught the eye of a passing woodpecker, who decided it was the perfect spot to make a home.

Unfortunately once he'd drilled his way in and created a nest, the pole became unsafe and had to be replaced. Unfazed by his forced eviction, the bird returned again to make a new hole for another home in the replacement. The pole had to be replaced a second time, since when there has been no sign of the woodpecker.

This picture shows the section of pole where the woodpecker made his nest.

Pair of glass insulators - from the Connected Earth collection, now at the Amberley Museum

Insulator collection : keeping the wires off the ground

These two insulators form just a fraction of a huge variety that have been used over the years.

The Connected Earth collection includes around 500 insulators which all share similar characteristics; they're around 10cm to 13cm long and made from non-conductive materials such as rubber, porcelain or earthenware to avoid electrical leakage from the bare line wires to earth.

The insulators came in many different shapes from all around the world including England, Germany, Russia, USA, even the Orkney Islands. The manufacturers registered a variety of patents claiming that their design was an improvement on what had come before. The rubber models were particularly useful against young boys hurling stones at the insulators trying to break them, which was a minor national pastime in the late 19th century.

BSA motorcycle combination - a Connected Earth artefact, now at the Amberley Museum

Lineman's motorcycle (c1933) : a neat way to get to work

Back in the 1930s the Post Office were busy installing telephones deeper and deeper into rural Britain. And with all the kit to carry, a bicycle just wouldn't do.

One answer was this motorcycle and sidecar. The sidecar wasn't for anyone to sit in but held the tools of the trade. A toolbox and spares (and frequently a lunchbox) lay in the top with a ladder folded and nestled into the bottom.

This BSA 595cc bike was used in London for a number of years before being sold. It was bought back by the Post Office in 1979 for complete restoration.

Morris Commercial truck

Morris commercial truck (1940s) : the head of the fleet

This was the standard vehicle used by the working gangs, who laid and fixed the network. It was big enough to carry spades, cement, cables and whatever else was needed to carry out the heavy work.

There was a companion trailer that could be attached to the back of the truck for even bigger jobs that needed extra kit. It also had a hooped cover that could be erected over the top of the trailer to give some protection to the crew and their equipment in bad weather.

fun and games

Can you beat our games? Explode equipment to see what's inside, hear the changing sounds of telecommunications, see how telecommunications designs have changed over time or send an e-postacard.

what's on

The UK's first permanent gallery dedicated to the history of information and communication technologies opens in the new Information Age gallery at London’s Science Museum.

audio history

Take a trip down memory lane with extracts of the interviews which have been recorded as part of the Connected Earth oral history programme.

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