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The Scientific Revolution

The Telephone

In the 1870's those new telephone fandangles were expensive and not a lot of use if no one else you knew had one. 

The McKie water business was an early adopter, no doubt to accommodate wealthy customers.  The first telephone was invented by the Scotsman, Alexander Graham Bell.  It had restricted range and required shouting into a variety of not very practical microphones, some even using pools of mercury, to convert sound to an electrical signal. 

Most microphones, particularly those in phones today, that are based on electret materials, require some kind of electrical amplifier to convert sound waves bouncing off a diaphragm into a useful electrical signal.  This was a major handicap prior to the invention of thermionic valves or transistors.  What was required was a microphone that would be its own amplifier. Three men had a similar idea: using a small container of granulated carbon as a variable resistor, arranged so that it would change its resistance to current when compressed and decompressed by a diaphragm moving to soundwaves, like the eardrum and associated components in your ear. 

A patent dispute followed in the US, with Emile Berliner, the inventor of the modern Phonograph (with records we would recognise) claiming priority.  This was resolved when the patent for the granular carbon microphone was eventually granted to Thomas Alva Edison in 1877.

The Bell Telephone Company quickly acquired the Edison patent in 1879.  Suddenly Bell Telephones could make calls the length of England, or even more impressively, trans-continentally across the United States or Australia or Russia.

Edison's invention was of incredible importance.  So, it is this for which he should be most remembered, not the light bulb or the phonograph.  The carbon microphone is an unsung but pivotal invention of the late nineteenth century.  It was still in use in every telephone handset and telephone box in the world until well into the second half of the 20th century. I've still got one in a box somewhere. 

The carbon microphone was not fully replaced until the 1980's when smaller microphones requiring semiconductor amplification could be used, mostly after electronics had been incorporated into handsets to facilitate tone-dialling.  It was also the basis of the first hearing aids.

The carbon microphone allowed the first public address (PA) systems to be built, advancing a new type of political demagogue at mass political rallies.

Perhaps equally importantly, the first singers who had not been trained project their voice, could heard throughout a large theatre, setting the stage for radio, movies TV and electronic communications.  Imagine a world without microphones.

 

The electric light bulb

Edison is often credited with the invention of the electric light bulb too - or simply 'electric light'.  But this is not so.

At the Newcastle Literary and Philosophical Society new things were afoot. On 3rd February, 1879 Sir Joseph Wilson Swan, demonstrated his Incandescent Electric Lamp to an audience of over seven hundred people. Then on the 20th October, 1880, during a lecture, Swan gave the signal for all the seventy gas jets to be extinguished and switched on twenty of his own lamps, which ‘amazed the audience with its suddenness.’

Thus, in 1879 the Newcastle Literary and Philosophical Society’s lecture theatre had been the first public room in the world to be lit by electric light bulbs. 

This event was to change my family's future and the entire World forever.

Eleven months later, on December 31, 1879, in Menlo Park in the US Edison would make his first public demonstration of an incandescent light bulb.  It was said that he had developed the idea entirely independently.  Who knows, he was a great borrower and improver.  His US patent was applied for a full year after Swan's was granted in England.

But neither had 'invented' electric light.

Sir Humphrey Davy, George Stephenson's nemesis, had invented the electric arc lamp in the early 1800s.  Electric arc lamps were already replacing gas limelight, used in live theatres, and are still used for some theatrical purposes.  They were used in cinema projectors until the 1990's as well as military searchlights and lighthouses and provided the first practical electric light. 

As a boy I helped make a little one with a tinplate can as the reflector, using Meccano and pencil leads for electrodes. My father oversaw the project to ensure I didn't blind or electrocute myself.  A carbon arc can be exceedingly bright but the lamps continuously consume carbon electrodes and generate a lot of heat. 

In 1800's they required a large bank of batteries and/or a dedicated dynamo and they are not suitable for continuous use for more than a few hours.

It's difficult for us to recapture the marvel of bright electric light.  The public was enthralled. Crowds would gather for public demonstrations of lighting. Searchlights can still impress and are sometimes used for movie openings.

For example as early as July 1880, Lt. Col Cracknell, Superintendent of Telegraphs for NSW (Australia), publicly lit one of the caverns at Jenolan Cave’s with electric light using arc lamps.  A small dam was then built and a turbo generator, using an American Leffel wheel, was installed to light the caves, in one of the first public electric light installations in the World.  You can still see the original plumbing as well as the more modern replacement turbines along the river walk below the dam.   The caves of course are spectacular and much loved by the McKies in Australia.  People travelled from England, when it took months, just to see them.

 

 

Jenolan Jenolan
Jenolan Jenolan
Jenolan Jenolan

 

Jenolan Caves Electrification - 1889  (my photos)

 

But arc lamps were poorly matched to domestic lighting.  Not only do they consume the electrodes but they also produce ozone that smells and may be harmful; considerable heat; and dangerous ultraviolet radiation.  The challenge was to produce an affordable long-lasting pollution free electric lamp suitable for continuous domestic use, that was at least as bright and reliable as a contemporary gas mantel.

Gas mantles are still used in the gas lamps people take camping.  They produce a dimmable bright white light that can be the equivalent of an incandescent bulb of several hundred Watts. 

 

Gas Lamps Westminster AbbeyTwin mantle gas lamps - still in daily use at Westminster Abbey - very bright

 

Almost every house I've lived in as an adult, including this one, was once lit by gas mantles and I've pulled out the remnants of old gas pipes from three of them.   

Edison realised that if an electric bulb could be developed, electricity from his direct current (DC) dynamos could be reticulated through cables and sold to a mass market to compete with gas.

He was in the process of developing perhaps the World's first commercial research laboratories. This complex, over two blocks in West Orange, New Jersey, included chemistry, physics, and metallurgy laboratories; a machine shop; a pattern shop; a research library; and rooms for experiments.  It came to be known as the 'Invention Factory' with dozens, and later, hundreds, of engineers and scientists developing patentable ideas.  Edison realised the bankable importance of his reputation as the world's greatest inventor.  Thus, the inventions and developments generated by his labs were almost always attributed to him personally. 

In this he had the financial backing of J. P. Morgan and the members of the Vanderbilt family, in addition to many smaller investors.  Whereas Swan was a scientist, for whom invention was a by-product of his curiosity and experimentation, largely backed by his own resources and interests.

Wanting to avoid another patent dispute like the one with Berliner over his microphone, Edison signed-up Swan in a joint company to manufacture and market light bulbs and he subsequently used a copy of this 'Ediswan Lamp' in demonstrations of 'his' invention.

 

Ediswan Catalogue
Ediswan Catalogue 1893  (Wikipedia commons)

 

The world's first commercial manufacture of Ediswan light bulbs began in South Benwell, Newcastle upon Tyne in 1881, just 2 miles (about 3 kilometres) from the McKie Soda Water factory. 

To differentiate between the bulbs, Edison developed the Edison Screw socket.  The unique appearance of the Edison version of the bulb helped reduce confusion in the American public's mind as to who had invented it. 

The original socket used by both is described in the publication Electric Illumination in 1885:  "As in the Swan and Edison systems...  When the lamp is dropped into position and rotated to lock the bayonet joint, the heads of its two terminal screws slide over the above-mentioned curved springs...  making a good contact, which is rubbed clean every time the lamp is removed or inserted." 

 

 

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Travel

Denmark

 

 

  

 

 

In the seventies I spent some time travelling around Denmark visiting geographically diverse relatives but in a couple of days there was no time to repeat that, so this was to be a quick trip to two places that I remembered as standing out in 1970's: Copenhagen and Roskilde.

An increasing number of Danes are my progressively distant cousins by virtue of my great aunt marrying a Dane, thus contributing my mother's grandparent's DNA to the extended family in Denmark.  As a result, these Danes are my children's cousins too.

Denmark is a relatively small but wealthy country in which people share a common language and thus similar values, like an enthusiasm for subsidising wind power and shunning nuclear energy, except as an import from Germany, Sweden and France. 

They also like all things cultural and historical and to judge by the museums and cultural activities many take pride in the Danish Vikings who were amongst those who contributed to my aforementioned DNA, way back.  My Danish great uncle liked to listen to Geordies on the buses in Newcastle speaking Tyneside, as he discovered many words in common with Danish thanks to those Danes who had settled in the Tyne valley.

Nevertheless, compared to Australia or the US or even many other European countries, Denmark is remarkably monocultural. A social scientist I listened to last year made the point that the sense of community, that a single language and culture confers, creates a sense of extended family.  This allows the Scandinavian countries to maintain very generous social welfare, supported by some of the highest tax rates in the world, yet to be sufficiently productive and hence consumptive per capita, to maintain among the highest material standards of living in the world. 

Read more: Denmark

Fiction, Recollections & News

On The Secret

There is an obvious sub-text to my short story: The Secret, that I wrote in 2015 after a trip to Russia. Silly things, we might come to believe in, like 'the law of attraction' are not harmless. 

The story is also a reflection on the difference between American and Australian stereotypes, that were evident from conversations on the cruise.

I lived in New York for some time and my eldest daughter was born there. I have visited the US fairly regularly since. It is, in many ways, the closest country to Australia that you will find, outside New Zealand.  So, I have often been surprised by how different it is in other ways to Australia, given the great similarities in the median standard of living, shared popular culture and immigrant demographics.

I have come to the conclusion that this stems from our different founding origins.

Read more: On The Secret

Opinions and Philosophy

Medical fun and games

 

 

 

 

We all die of something.

After 70 it's less likely to be as a result of risky behaviour or suicide and more likely to be heart disease followed by a stroke or cancer. Unfortunately as we age, like a horse in a race coming up from behind, dementia begins to take a larger toll and pulmonary disease sees off many of the remainder. Heart failure is probably the least troublesome choice, if you had one, or suicide.

In 2020 COVID-19 has become a significant killer overseas but in Australia less than a thousand died and the risk from influenza, pneumonia and lower respiratory conditions had also fallen as there was less respiratory infection due to pandemic precautions and increased influenza immunisation. So overall, in Australia in 2020, deaths were below the annual norm.  Yet 2021 will bring a new story and we've already had a new COVID-19 hotspot closing borders again right before Christmas*.

So what will kill me?

Some years back, in October 2016, at the age of 71, my aorta began to show it's age and I dropped into the repair shop where a new heart valve - a pericardial bio-prosthesis - was fitted. See The Meaning of Death elsewhere on this website. This has reduced my chances of heart failure so now I need to fear cancer; and later, dementia.  

More fun and games.

Read more: Medical fun and games

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