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The telegraph

The telegraph was the first form of telecommunication. 'Telegraph' means 'writing from far away' or 'distant writing' and the word originally applied to semaphore systems. But the search for ways of sending signals over long distances had been around for thousands of years.

First steps
The first telegraph systems were developed thousands of years ago.

They used many different ways of signalling: smoke, fiery beacon, drums, lights, mirrors, flags and semaphores. But the basic idea was always the same - transmit a message faster than a man could run or a horseman could ride.

The limitations were always the same, too. Signals had to be relayed in stages defined by how far a human could see or hear. And the signals had to be simple, or in a code.
Looking for the electric telegraph
For thousands of years, people dreamed of being able to exchange messages further than they could see or hear. But this meant discovering something that would work independently of sight or sound.

That something was electricity - discovered in the mid 18th century. So the idea of an electric telegraph goes back further than you might think.
The first electric telegraphs
When the electric telegraph finally arrived in the early 19th century, it was a real breakthrough.

It had needed three ingredients to make it reality: the science of electromagnetism, the ability to generate or store electricity and the Industrial Revolution to be able to produce the mechanical devices and wires needed.

But there was one more key - the creation of codes to turn electrical pulses into a kind of language. During the first decades of the 19th century, all the elements finally fell into place.
The telegraphic age dawns
By the time Queen Victoria came to the throne in 1837, many inventors had built simple electric telegraphs - but no one had managed to construct a working commercial system.

That year, however, the race was won by two Englishmen - William Cooke and Charles Wheatstone. They were first to patent a working system.

At the same time, though, an American inventor, Samuel Morse, was perfecting his version of the telegraph - and it was Morse's system that came to dominate the future.
Development of the telegraph
The first telegraphs were cumbersome and slow - but as the telegraphic age progressed the world started to move faster. More and more messages had to be sent - at greater speed and over longer distances.

New types of telegraph had to be invented - and new ways to cram more information down those thin wires. This constant search produced new types of telegraph and took the inventors into new and unexplored areas that would eventually lead to entirely new kinds of telecommunication.
Building telegraph networks
The telegraphic age produced a new phenomenon - the wiring of a nation into a network. Wired networks are so much a part of life today that we hardly think about them - but the first telegraph wires seemed both alien and wondrous in Victorian times. The construction of that first network required huge feats of engineering and also gave rise to some hard fought battles.
Developing telegraphic services
Being able to send messages by telegraph was all very well - theoretically. But why would you want to? Life in the 1840s still moved at the speed of the horse and carriage. There was one exception - the railway. They needed to be able to send messages faster than the trains could travel - and, at that time, trains were the fastest things on Earth.

As the railways speeded up the pace of life so did the telegraph - with the infant telegraph companies having to adapt their services to the new realities of a fast changing world.
International telegraph connections
By the 1850s, telegraph lines crossed Europe and spanned the United States. But there was a final frontier to cross - the ocean. In the mid 19th century, laying a cable under the sea required almost unimaginable levels of investment, engineering expertise and navigational skill - the equivalent of space exploration today. Yet there were men with the money and the determination to take on the challenge - and win.
Into the 20th century
The First World War marked the peak of the telegraph era. Diplomatic telegrams sped Europe's slide into the abyss, cabled military orders triggered mass mobilisation and the knock of the telegram messenger forewarned mothers and wives that the worst had happened.

After the war, the world of communications belonged increasingly to the telephone and the radio. Nevertheless, the telegraph was far from finished - its life extended by newer and more sophisticated devices.

The telephone

The telephone was based on the telegraph and used electrical signals carried along copper wires. Instead of an on-off signal, it carried a replica of the sound waves created by a human voice. For the first time, people could use this 'analogue waveform' to communicate over distance.

First steps
The telephone was discovered almost by accident. What people thought they were looking for was a way to make the telegraph work faster and more profitably - by sending distinct musical notes or tones simultaneously along the wires with a separate message sent on each frequency.

But they soon realised it could also include the human voice - a speaking telegraph. And if you could talk down a wire, wouldn't that be an entirely new and better way of communicating?

The individual parts of the telephone were discovered and developed by different people at different times.

Someone needed to take all those connections and draw them together into one working instrument. In the end that someone was Alexander Graham Bell - but he only just won the race.
Developing the telephone
Owning a telephone was all very well - but not much use without someone to call . It was one of many 'chicken and egg' situations in the history of telecommunications - which comes first, the network or service? The application or the need?

Without selling telephones, you have no users. But without a group of users, other people have no reason to buy a telephone. Breaking through this barrier involved some hard selling - and some tough business battles.
From local to national networks
The first telephone networks were tiny, connecting a handful of users in closely located buildings, with a small switchboard in between.

But it didn't take long for those networks to grow from tens of people to hundreds, then thousands.

At the same time, the local networks began to be connected together as trunk lines were set up - long distance wires connecting the towns and cities all over Britain.
International networks
As we stand at the beginning of the 21st century, there are four main trends that are shaping the world of telecommunications, media and entertainment.
Those trends are digitalisation, convergence, fragmenting audiences and the growth of the internet.

Mobile communications

The introduction of mobile phones took over half a century. The introduction of radio telephony in the 1920s made it theoretically possible for people to talk on the move. However, effective deployment had to wait for the development of computers to allow networks to be created and miniaturisation to make the devices small enough to be really mobile.

When true mobile telephony finally arrived in the early 1980s it was a revolution - for the first time telecommunications really was person to person rather than just place to place.

The origins of mobile
Mobile telephones had been around for almost 60 years before we got our first cellphones in the 1980s.

To start with there were radiotelephones for ships, aircraft and military vehicles. Then radiophones for cars and finally personal mobiles.

The theories for cellular mobile telephony were shaped by the 1940s - but getting there would take a further 40 years.
The first true mobiles
All the basic technologies for mobile phones were in place from the late 1940s: wireless, telephony, cellular network design and frequency re-use. All that it required was the software and hardware to make it work.

But it was to prove difficult to come up with something that would work - and something that people would want to use.
Building the networks
All telephones are only as good as the network supporting them - and that's certainly the case when we use a mobile phone.

With cellular networks, design and equipment not only dictates whom we can call - but whether we can call at all. 'No service'are not good news for any mobile user.
Finding new markets
The world got along fine without mobile phones for 100s of years... but that wasn't to say people didn't want one. After all, who knew they wanted a car, computer or dishwasher.

The arrival of the truly individual telephone with its own special number was a revolution - and one that changed people's attitudes to keeping in touch. But for the revolution to take hold, some sweeping changes and innovations were required.

A wireless world

Wireless did what its name suggested - it did away with the wire connecting sender to receiver. This meant that telegraphy, then telephony, could be extended across oceans and around the world. Wireless signals could be picked up by any number of receivers, but range proved a problem.

The origins of radio
Radio developed as a logical next step from telegraph - the need to find a way to send telegraph signals over of water without cables. But the discovery process goes back much further than that - and features some remarkable leaps of deduction - as well as feats of technological daring.
Wireless comes of age
With the development of wireless, we moved a big step closer to a 'joined up world' - in which every part of Earth was brought within contact.

The technological development that made this possible involved wireless going to sea and taking to the air. The development of radio telephony allowed real conversations over the airwaves - and extended the reach of the telephone.
Radio was the first means of instant mass communication - allowing the possibility to talk to whole populations at once. From the late 1920s on, important events started to become shared experiences for entire nations.

In Britain the technology of broadcasting evolved rapidly so that in just ten years it was accessible to millions of people all over the country.

The video age

Television means being able to view moving images at distance and video allows us to record and replay picture and sound. Both are part of daily life.

TV was invented over 70 years ago but its progress from the first black and white images to colour took little more than 25 years.

The origins of television
The basic principle of television is a little like that of film and works because of the way we see. When we look at a series of still images send rapidly and sequentially, the trace of each one lingers at the back of our eyes even as the next is being seen. Therefore our brains translate the sequence of still images into one continuous moving one.

The invention of television meant finding ways to capture movement as a series of still images and then separating them into strips (scanning) to allow them to be transmitted as electrical signals - down wires or over the airwaves.
Developing television
Television got off to a slow start. This was a new and expensive form of entertainment and the technology was far from assured.

Even before World War Two intervened to close television broadcasting operations in most countries for the duration, television showed every sign of catching on in a big way.

Maybe the real surprise is how much investment was made in television - and how quickly.

Satellite and microwave

The story of microwave and satellite transmission is about harnessing the power of high intensity radio waves and focussing them between fixed points on Earth - or in Space. We may think that these are 'Space Age' technologies but their story starts well over 70 years ago.

Origins of microwave
In a sense, microwave and satellite links go right back to one of the ancient principles of primitive signal beacons - that you need a line of sight between two points.

The difference is now the two points can be thousands of miles apart - and not even on the surface of the Earth.

Microwave is one of the most effective technologies in the telecommunications field - a system that allows huge amounts of data or voice signal to be beamed from point A to point B.

Why did we need microwave links? Once again it was the need to send more messages ('bandwidth') that pushed technological progress. Wartime experience with radar showed how dish antennas could be used to focus beams of energy that could carry large amounts of information.
Into space
The start of the space age can be dated from two separate events towards the end of World War Two. First was the development of rockets that could escape the Earth's atmosphere - and with it, the potential to fire objects into orbit.

The second was the realisation that those orbiting objects - called satellites - could be used as reflectors to bounce signals around the Earth...
The first satellites
The theory of satellites was simple enough - shoot something out into space at the right speed and on the correct trajectory and it will stay up there, orbiting Earth, for years - if not forever.

And if that orbit is just the right distance out in space the satellite will keep pace with the rotation of the Earth - remaining on station out there in the skies.

Theory was one thing - but achieving the vision was not so simple.
Satellite tracking
The technological challenges faced by the pioneers in satellite communications were enormous. They had to find ways of tracking relatively tiny objects in space - objects that were moving at thousands of miles an hour.

And with the primitive computers of the time that stretched the technology of the 1950s and 1960s to the very limits.

But their success paved the way for the 'Global Village' and introduced a new era in television.
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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