Richard Ambrose explores the history of the telephone. The technology that founded the telephone system consisted of a string and cup. It has radically evolved through fiber optic and computer technology.
", "is_us_only": "false", "title": "I Didn't Know That: The Telephone", "url": "http://video.nationalgeographic.com/video/science/weird-science-sci/idkt-telephone/", "country_code_deny_list": [], "allowUserEmbed": "True", "related": { "link": [ { "url": "http://science.nationalgeographic.com/science/", "name": "More About Science" } ] }, "credit": "National Geographic", "smil": "http://video.nationalgeographic.com/video/player/data/xml/idkt-telephone.smil", "country_code_allow_list": [], "HTML5src": "/video/player/media-mp4/idkt-telephone/mp4/variant-playlist.m3u8", "still": "http://video.nationalgeographic.com/exposure/core_media/ngphoto/image/55274_0_616x346.jpg", "transcript": "RICHARD AMBROSE: This is the technology that founded our entire telephone system; it's the cup and string telephone.\u00a0 This end has been rigged by our sound man Darren to mimic placing it to your ear with a microphone, I'm going back 30 meters to show you how well it works. Can you hear me?
DARREN: I can.
RICHARD AMBROSE: Excellent. The plastic cup I'm holding acts as a diaphragm, so every time I make a sound it vibrates.\u00a0 As long as the string is taught those vibrations travel to the cup at the other end that cup also acts like a diaphragm and converts those vibrations back into sound so you can hear my voice.
This is basically transmission of sound by telephone and its discovery in the 18 hundreds sparked off a race to produce the first device to transmit human voice by wire.
This is Elijah Grey you may not know him because it was Alexander Graham Bell who in 1876 reached the patent office first by a matter hours.\u00a0 Soon after workers began stringing out copper wires across the nation to carry telephone conversations and new phrases started to enter the English language, like 'ring off' and 'she's hung up on me'.
At first telephones were considered to be so ugly that they didn't want them on display, so things like the crinoline lady were developed to cover them, oh isn't that better? Later when telephone use became more wide spread people wanted to make their phones different so they bought these lovely covers like this velveteen thing, it really is nasty.\u00a0 But when people started to buy their own telephones the designers really went crazy.
Now listen to this, each key not only plays a note but dials a number great.
Operator girls put through the calls, but at 8pm they clocked off as they weren't allowed to work the night shift and if they got married they had to give the job up. Over time they were gradually replaced with electronic switches developed by an American undertaker called Strowger.\u00a0 As well as being sent along cables phone conversations began to be transmitted on high frequency radio signals called microwaves.
In the 1980's our phone system began to go digital and our old cabling system was replaced by this optical fibre. It's just a sliver of glass that's as thin as a human hair and it's so pure that if it was 20 km thick you could see straight through it, and cables made of optical fibres can carry billions of bits of information at once.
Slowly the whole network is being linked with optical fibres, they allow our voices to be carried along like pulses of light, which makes them arrive quicker and clearer.
Mobile phones first appeared in the 1980's; at first only a few people owned them, mostly for business use, now there are over 60 million mobile phones in use in the UK.\u00a0 In the 1990's the growth in home computing meant phone lines were increasingly used to link PC's to the internet.\u00a0 Our love of surfing the net or just chatting means the phone is here to stay.
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