Do we still need the telephone?
Just as the use of social media divides opinion, so the arrival of telephones in the office was once seen as a radical intrusion, explains Lucy Kellaway.
As I sit at my desk I can hear the distant hum of a photocopier, a mobile phone vibrates along a table and somewhere far away a printer runs out of paper.
The office has become a very quiet place indeed.
Technology has changed the sound of office life. For a hundred years it was a noisy place, filled with the sound of telephones and typewriters. Now it is almost silent - just broken by the gentle sound of someone saying: "Nipping out to get a latte. D'you want one?"
In the beginning there were just paper and quills. Then came the typewriter, which brought with it a number of other late 19th Century breakthroughs - the filing cabinet, the adding machine, and in particular the telephone.
But what did these inventions mean? And did they make office life better or worse?
In the stores at the Museum of London there is a sort of giant graveyard full of old office machinery. Row after row of adding machines fill the shelves.
The earliest model is the Burroughs adding machine, which could calculate relatively complicated sums with its rows of keys and pull handle.
Another breakthrough came in 1870 - the filing cabinet. In the dark ages before this simple bit of furniture was invented, clerks wrote everything down in massive ledgers and on pieces of paper tied up in bundles. If the clerk left or died suddenly, any chances of finding anything often died with him.
With the cabinet, information could be arranged alphabetically, which meant it was theoretically possible to find it again. That was great - what wasn't so great is that this created an entire industry of unnecessary work.
I worked as a filing clerk briefly in the late 1970s and there was nothing more dispiriting than stuffing paper into bulging files knowing perfectly well that no-one would ever look at it again.
On one estimate, the UK in the pre-computer age shoved more than two million tonnes of paper into filing cabinets every year. Unnecessarily.
These new devices increased efficiency but didn't really change the nature of business.
Then came the telegraph.
"What hath God wrought," said the first long-distance telegraph by Morse Code in 1844. And what God had wrought turned out to be a very big deal indeed.
The telegraph was the Victorian internet. It made the world global. It meant you could do business without actually being there. It released the manager from the factory. It meant that the prices on the Paris stock exchange were known the same day in London.
The spread of the telegraph was almost as fast as Facebook today. By 1887, 50 million of them were being sent a year in the UK, almost all for business.
The beauty of the telegraph was that it invented brevity long before Twitter made it cool. But it also invented scarcity. Because it was expensive in its earliest form - it was the equivalent of about £80 today - you only sent a telegram if you actually had something to say. Would that were the case today.
But in 1876 came the telephone, and with it a new sort of behaviour. The telephone created an informality that the telegraph never aspired to.
The telephone made business big. Easy communication encouraged the growth of sprawling multinationals with offices everywhere. It also made them tall - without it the skyscraper never would have caught on.
As one AT&T engineer put it in 1900: "Suppose there was no telephone and every message had to be carried by a personal messenger. How much room do you think the necessary elevators would leave for offices?"
In the US they couldn't get enough of the phone. By the end of the 1920s, 40% of households had them.
Telephones made business democratic - a man on the factory floor could talk directly with the boss without having to go through all the levels in between.
"It gives a common meeting place to capitalists and wageworkers," wrote Herbert Casson in his 1910 book The History of the Telephone.
"It is so essentially the instrument of all the people, in fact, that we might almost point to it as a national emblem, as the trademark of democracy and the American spirit."
The enthusiasm wasn't shared in the UK. William Preece, chief engineer of the General Post Office, declared that the new gizmo was merely "a substitute for servants".
"There are conditions in America which necessitate the use of such instruments more than here," he told a House of Commons committee.
"Here we have a super-abundance of messengers, errand boys and things of that kind. The absence of servants has compelled America to adopt communications systems for domestic purposes. Few have worked at the telephone much more than I have, I have one in my office but more for show. If I want to send a message - I employ a boy to take it."
By 1880, the first ever British phone directory had a mere 285 names - all of them London business, and mostly traders, dealing in everything from sugar to ostrich feathers.
The Bank of England, never one to hurry into anything, was not connected until 1902 but then they were still buying quills till 1907.
The merchant bank Schroders refused to have its name in the telephone directory, for fear that incoming calls caused distraction.
And at the Hong Kong and Shanghai Bank, the phone was regarded with such suspicion that operators had to answer with the words, "I am the Hong Kong and Shanghai Bank".
People worried that the phone took away their privacy, in much the same way that we now fret over social networking. But by 1927, telephone calls were flooding in at an average of one every 1.5 days.
Women were the new masters of the telephone, just as they were with the typewriter. A new kind of an office was emerging - the telephone exchange - and women were deemed just the people to operate it.
"The dulcet tones of the feminine voice seem to exercise a soothing and calming effect upon the masculine mind," noted an early telephone engineer.
There was actually nothing soothing about working a switchboard. It was relentless and exhausting, involving cumbersome apparatus and the speedy plugging and unplugging of cords at various heights and, of course, dealing with the public, who weren't easy to please.
The Times complained about uppity switchboard girls. "Too many of the operators seem to regard the telephone user as their natural enemy and treat him with utter nonchalance, if not with an insolence and impertinence, which are all the more irritating because there appears at present to be no remedy for them."
The new technology meant a new etiquette. In 1910, the telephone company Bell put out a booklet called Dr Jekyll and Mr Hyde at the Telephone.
Some of its lessons were simple - "Speak directly into the mouthpiece keeping moustache out of the opening" - advice I've always followed.
Saying hello was much frowned upon too.
"Would you rush into an office or up to the door of a residence and blurt out 'Hello! Hello! Who am I talking to?'" asked Bell. "One should open conversations with phrases such as 'Mr Wood, of Curtis and Sons, wishes to talk with Mr White...' without any unnecessary and undignified 'hellos'."
And as for ending a call, a 1926 telephone magazine advised that it was up to the caller to signal the end, unless a man and a woman were speaking, in which case it was up to the "second sex" to ring off first.
But that was all in the US. The UK, meanwhile, continued to lag behind. In 1914, we had the worst telephone service in the civilised world, according to the Quarterly Review.
There were then fewer than two telephones per 100 people in the UK compared with 10 in US. It was not until after 1919 that the telephone really spread.
But by middle of the 20th Century most workers had a phone on their desk. They got used to the constant ringing and interruptions. People didn't get up to talk to each other, they spoke on the phone instead. The office switchboard was the hub of office, a sort of social glue connecting everyone to everyone else.
And that's how it stayed - until the last couple of years. We are now witnessing the death of the office landline, and with it the main switchboard.
If anyone really wants me, they send me an email, and because I don't like random disturbances any more than the Edwardians did, I've stopped answering my desk phone altogether.
The other day I checked my voicemail and found 100 messages stretching back over weeks. Guess what I'd missed? Nothing of any note at all.
This piece is based on an edited transcript of Lucy Kellaway's History of Office Life, produced by Russell Finch, of Somethin' Else, for Radio 4. Episode five, The Telephone and New Office Technology, is broadcast at 13:45 BST on 26 July. Episode six, The Invention of the Manager, is broadcast at 13:45 BST on 29 July.