Focus, Issue 100, March 2001
Millennial minds: Nikola Tesla
Forgotten genius of light and power
(image): Tesla lights Las Vegas - Huge amounts of power can be used to illuminate fluorescent lights, which Tesla invented.
(image) Nikola Tesla invented the AC dynamo - the technology that lies behind electric light
Victim of corporate backstabbing, Nikola Tesla tragically was never recognised for his outstanding work on electrical technology.
The man digging the trench cut an unusual figure: tall, thin - elegant almost: certainly not a typical labourer. His background was more incongruous still. Born the son of a Croatian priest 31 years earlier, he held a degree in engineering, and in 1884 had emigrated to the US hoping to find his fortune. What he had found instead was double-dealing and deception. Now, three years later, he had been reduced to digging sewers.
Yet within a few months, Nikola Tesla would be at the centre of a technological revolution that would transform the world. Combining brilliant scientific insight with engineering skill, he brought light and power within reach of millions. His discoveries ranked with Faraday's, and his impact on today's world outstrips even that of Edison. He was truly the modern Prometheus, whose findings still inspire researchers today.
Despide all this, however, few know of Tesla. The tragic story of how someone can achieve so much, yet die alone and all but forgotten serves as a stark reminder that mere genius is no guarantee of fame or fortune.
It could easily have turned out differently. Certainly, the omens of greatness were spookily apparent at Tesla's birth in 1856. His mother went into labour as a violent electric storm thundered around the small village of Smiljan in Croatia. On the stroke of midnight of 10 July, she gave birth - prompting the midwife to declare that Nikola must be a child of the storm.
Dynamic Achievements
The young Tesla lived up to the promise of his spectacular birth, showing a fascination with electricity from an early age. Academically gifted, he studied engineering at the Technical University of Graz, Austria. It was there that Tesla came across an electrical device that would inspire him to make his greatest achievements.
Known as a 'Gramme dynamo', it used coils of wire inside a magnetic field to act as a motor - creating motion from electric current and vice versa, as a generator. Tesla, now 22, told his teacher that he could radically improve the dynamo's clumsy design. Four years later, he succeeded - with a brilliant design featuring two 'alternating currents' (AC), which ebbed and flowed to create magnetic fields that drove the motor.
Wanting to demonstrate his highly-efficient new 'AC induction motor', Tesla moved to Paris to work for Continental Edison, the European arm of the famous American inventor's technological empire. There, he could show the power of his invention, using his induction motor to help Edison's company complete a prestigious lighting contract in Strasbourg.
His success led, in 1884, to a call to join Edison himself. At first sight, this was a match made in heaven: Edison had enormous drive and commercial sense, but no aptitude or patience for theory. Tesla, on the other hand, knew that truly amazing new inventions could flow from a deep understanding of the laws of physics. Had they been able to work together, the results would have beggared belief. As it was, they soon became bitter rivals.
Both were to blame. Edison was determined to exploit fully his invention of the electric light, and made promises of huge bonuses to Tesla for breakthroughs that would help Edison's cause. But when Tesla delivered, he repeatedly reneged on the deal. Tesla, on the other hand, blithely expected Edison to abandon his huge investment in his lighting technology to back Tesla's own ideas.
From ditches to riches
It was this clash of ruthlessness and naivety that, in 1887, led to Tesla quitting Edison's company and ending up digging ditches. It also led to the infamous 'Battle of the Currents'. For, during a break from his labouring, Tesla regaled his foreman with amazing tales of what electricity could do if only he were given the chance to develop his ideas. As luck would have it, the foreman had a friend on the lookout for investment opportunities, and arranged a meeting. Within a few months, Tesla's fortunes had been transformed. He had his own business - the Tesla Electric Company - and raced to patent the key technology needed for a whole new electrical technology based on AC.
Tesla's big break came just as Edison was struggling with his own technology, based on direct current (DC) generated by batteries. Despite its simplicity, DC technology had a crucial flaw: it could only generate relatively modest voltages, whose power dwindled hopelessly after travelling barely half a mile through the wires. Edison would have to build power stations every 1,000 yards to bring the voltage back up to 100V or so - a ludicrous prospect.
Tesla's AC technology faced no such restrictions. Using AC transformers, its initial voltage would be stepped up to 300,000V or more, allowing huge amounts of power to be sent for miles before being stepped down to safer levels again by another set of transformers.
Despite AC's clear superiority, however, Edison's huge investment in DC meant that he could not stand by idly and let Tesla's system win. Battle was joined in 1888, by which time Tesla had joined forces with another deadly rival of Edison, the industrialist George Westinghouse.
First blood went to Edison, who seized on the dangers of his rival's high-voltage AC system. His company arranged for the media to witness stray dogs and cats being 'Westinghoused' - electrocuted by standing on metal plates connected to AC supplies. He also contrived to ensure that New York State introduced a new form of capital punishment: the Electric Chair, again featuring AC current.
Westinghouse retaliated by showing that Edison's DC current could cook a whole side of beef in just 100 seconds. It was a PR stunt, but one utterly eclipsed by the horror of the first use of the Electric Chair on a convicted murderer on 6 August 1890.
Desperate for an impressive media coup, Westinghouse took a huge gamble: he would use Tesla's untried AC system to save the livelihoods of hundreds of miners. The Gold King Mine in Colorado was threatened with closure because it had become uneconomic. Everyone knew that the nearby river could provide cheap hydro-electric power that could keep the mine open. But the river was more than two miles away - beyond the reach of Edison's DC system.
[inset] Tesla and the mystery of ball lightning
(image) While testing his Tesla Coil, Tesla also experimented with lightning.
Given his fascination with the awesome power of lightning, it was inevitable that Tesla would be drawn towards its greatest mystery: the origin of ball lightning.
Reports of strange glowing balls of light that float over the ground during thunderstorms have been circulating for at least 200 years. Typically measuring about 30cm (12inc) across, ball lightning glows like a 100W light buld - yet has no obvious power supply. It's usually linked to thunderstorms, but rarely has it been directly linked to a strike of lightning. Those who've come into close contact with it say it doesn't seem to emit any heat - yet there are reports of it melting glass.
High voltage. Tesla's attempts to study this bundle of paradoxes began in 1899, at his remote electrical lab in Colorado. Using specially-designed high-tension electrical machines, he was able to generate voltages far above those produced in natural thunderstorms - up to 100 million volts.
Tesla found, however, that raw power wasn't enough to trigger ball lightning and, despite his efforts, he failed to create it in his lab. Success came later, in experiments in which electrical discharges came into contact with organic matter, such as wooden objects in the lab.
Tesla came to the conclusion that ball lightning was due to thunderbolts striking such objects and vaporising them, creating a mix of hot, electrically charged matter that floated over the ground.
As usual, Tesla seems to have hit on the right idea ahead of his time - and then been forgotten. In february 2000, scientists in New Zealand came up with what many regard as the best explanation of the many bizarre properties of ball lightning - and it centres on thunderbolts vaporising material, just as Tesla had suggested.
(image) Buzzing with new ideas - in his remote Colorado Lab in the Rockies, where he often gave exhibitions, Tesla carries out experiments with spark discharges.
(images) Tycoons George Westinghouse and Thomas Edison joined forces, after winning the contract to install the first power machinery at Niagara Falls - harnessing its colossal energy using tesla's AC technology.
(image) Marconi, didn't invent radio - as many still eblieve - Tesla did
[inset] Tesla and the health benefits of electricity
Tesla's obsession with health led him to conduct a series of bizarre experiments into the potential medical benefits of electricity. While alternating current (AC) can be extremely dangerous - as Edison has demonstrated via the Electric Chair - Tesla found that very high-frequency AC passed only through the outer layers of his skin, making it relatively safe.
Mellowing. His experiments resulted in the Tesla Therapeutic Electrotherapy Machine, which was said to "promote heart action and digestion, induce healthful sleep, rid the skin of destructive exudations and cure colds and fever". The machine consisted of a battery and coil wired up to two copper cylinders, which the patient held in each hand. Once current passed through the circuit, it produced a tingling sensation. Whether the machine actually saved "thousands of lives" each year, as its maker claimed, was somewhat doubtful.
What Tesla did discover, however, was that electricity had an effect on the brain. Passing AC current through his head, Tesla noticed that he became drowsy - prompting him to suggest that perhaps it might one day become a form of anaesthetic: today, 'stun guns' are used routinely to put animals to sleep in abattoirs.
Tesla's belief in the health-giving properties of electricity survives in one highly controversial form: electro-convulsive therapy (ECT).
Effective Jolts. First attempted by psychiatrists in Italy in 1938, ECT uses electric shocks to trigger epileptic fits in patients with severe depression. For reasons still not understood, ECT seems to be very effective, rapidly bringing patients back from the brink of suicide.
However, as Tesla himself discovered, ECT is not without side-effects. Around one in ten patients suffers from some memory loss - and many find the experience traumatic. While doctors insist that it is still the most reliable way of rapidly treating life-threatening depression, ECT remains deeply controversial.
(image) ECT: electric pulses are transmitted via two electrodes
The light fantastic
Westinghouse was convinced that Tesla's AC system could cope, and in 1891 the world's first Tesla industrial supply began feeding electricity to the mine. With this first victory over Edison in the bag, Westinghouse took another big gamble, and accepted a contract to provide electric lightning for the 1893 World Fair Chicago.
It proved to be another triumph - underlined by the presence of Tesla, who amazed visitors by passing AC current safely through his body and lightning electric lamps with his fingertips. The game was up for Edison. With the failings of his DC system all too apparent, he quit the business to pursue other interests. His company signed a deal with Westinghouse to get access to Tesla's AC technology, and together the former rival companies worked to harness the hydroelectric power of the Niagara Falls. The opening of the power station in 1895 signalled the end of the Battle of the Currents - with total victory for Tesla.
Not that he got his rightful reward: once again the corporate suits ran rings around him, with the westinghouse company cheating him out of millions of dollars. And once again Tesla failed to notice, content just to have research funding. For he was far from finished in his efforts to harness the powers of electromagnetism.
Tesla's 'party trick' at the World Fair was just a spin-off from a host of amazing discoveries he'd made during the early 1890s. They included the invention of fluorescent gas lightning, and experiments with X-rays and radio waves years before they were made famous by others (a US court declared in 1943 that Tesla, not Marconi, invented radio). His most important invention, however, was the so-called Tesla Coil, which allowed him to create electric current that alternated at very high frequency. Tesla found that such AC electricity had many bizarre properties, including the so-called 'skin effect', by which high-frequency AC travels only along the outer surface of wires. It was this that allowed him to pass electricity across his body at very high voltages - the secret of his World Fair stunt. More importantly, the Tesla Coil opened the way to radio and TV transmission, and to Tesla's most amazing discovery: the transmission of electrical power through thin air.
In a remote lab in Colorado, Tesla constructed a gigantic coil for creating powerful high-frequency electromagnetic fields - and succeeded in sending 10,000 watts through the air to light 200 electric lamps more than 40km away.
Stabbed in the back
Not surprisingly, Tesla believed he had made a historic breakthrough - one that could bring power to the whole world. But to prove it, he needed more money, and in 1900 he won backing from the famous financier John Pierpont Morgan, in return for handing over control of his patents.
In signing, Tesla again fell victim of the corporate suits. Morgan had made big investments in the fledgling AC electric companies, and he wasn't about to let Tesla's new wireless power system make them obsolete. So Morgan played Tesla along for four years - and then stopped paying him. Robbed of both backing and his own patents, Tesla's dream of wireless power was dead. He was back to square one, penniless and jobless, at 50.
Over the following years, Tesla became a pathetic figure, living alone in hotels and living off popular journalism and a small pension from his home country. Sometime between 5 and 8 January 1943, he had a heart attack and died in a New York hotel, aged 86.
Had Tesla possessed a fraction of the guile and low cunning of his great rival Edison, he would have won an exalted place in the pantheon of invention. Instead, his name is remembered only as a unit for measuring magnetic fields: the 'tesla'. It is scant reward for the misunderstood genius who brought light and power to billions of people at the flick of a switch.
Robert Matthews
For more information
http://www.neuronet.pitt.edu/~bogdan/tesla/
http://www.virtualtheater.com/tesla-bio.html
[inset]Shedding the light on Tesla
"I've had many hard-working assistants, but you take the cake"
- Edison to Tesla
"If Edison had a needle to find in a haystack, he would proceed at once with the diligence of the bee to examine straw after straw until he found the object of his search"
- Tesla on Edison
"Nikola Tesla: Our Foremost Electrician - Greater Even than Edison"
- Us press on Tesla
"What is electricity? Eighty years have gone by, and I still ask the same question, unable to answer it"
- Tesla
"The man who gave electricity to the world was Nikola Tesla ... a scientist of dazzling brilliance, a prophet who really did see into the future"
- Dr Robert Lomas, biographer
|
 讓我們程式搜尋結果更加完美 如果您覺得該文件有幫助到您，煩請按下我如果您覺得該文件是一個一無是處的文件，也煩請按下我 |
|
該文件您看起來是亂碼嗎？您可以切換編碼方式試試看！ISO-8859-1 | latin1 | euc-kr | euc-jp | CP936 | CP950 | UTF-8 | GB2312 | BIG5 |
|