Nikola Tesla



         


July 10, 1856 - January 7, 1943) (Baptism name: Николай; Nikolaj; Name in Cyrillic alphabet: Никола Тесла) was a Serb-American physicist, inventor, and electrical engineer, born in the village of Smiljan near Gospić in Austria-Hungary, on a territory which is today in Croatia. Tesla's most famous contribution was the theory of polyphase alternating current electricity, which he used to build the first induction motor in 1882, as well as developing the designs of numerous other electrical machines and related technology. His theory and many of his patents form the basis for the modern electric power system. Tesla is also noted for inventing the Tesla coil and a bladeless turbine (which functions on the principles of fluid viscosity and the boundary layer effect).

Life magazine, in a special double issue, listed Tesla in the "100 Most Important People in the Last 1000 Years". He occupied the 57th position, cited as "[one of] the most farsighted inventors of the electrical age". They state his work on the rotating magnetic field and alternating currents helped electrify the world.

The scientific compound derived SI unit measuring magnetic flux density or magnetic induction (commonly known as the magnetic field B), the tesla, was named in his honor (at the Conférence Générale des Poids et Mesures, Paris, 1960).

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Biography

Some additional information is available in Biography of Nikola Tesla.

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Early years

Tesla was born in Smiljan near Gospić, Lika, (the Military Frontier (Krajina) of Austro-Hungarian Empire, now in Croatia). His Baptism Certificate reports his birth at June 28 (Julian calendar; July 10 in the Gregorian calendar), and baptised in the Old Church Slavonic rite by the Serb Orthodox priest, Toma Oklobdžija.

His Serb father, the Rev. Milutin Tesla, was a priest in the Serb Orthodox Metropolitanate of Karlovci. His mother, Đuka Mandić, from a prominent Serb family of the Banija, made home craft tools. Tesla was one of five children, having one brother and three sisters. His godfather, Jovan Drenovac, was a Captain in the Krajina army. His family moved to Gospić in 1862.

Tesla went to school in Karlovac (Austria-Hungary), then studied electrical engineering at the Austria Politechnic in Graz, Austria (1875). While there, he studied the uses of alternating current.

In 1881 he moved to Budapest to work for the telegraph company, American Telephone Company. On the opening of the telephone exchange in Budapest, 1881, Tesla became the chief electrician to the company, later engineer to the Yugoslav government and the country's first telephone system. He also developed a telephone repeater (or amplifier).

For a while he stayed in Maribor. He was employed at his first job as an assistant engineer. Tesla suffered a nervous breakdown during this time. In 1882 he moved to Paris to work as an engineer for the Continental Edison Company on designing improvements to electric equipment. In the same year, Tesla conceived the induction motor and began developing various devices that use rotating magnetic fields (for which he received patents in 1888). Tesla hastened from Paris to his mother's side as she lay dying, arriving hours before her death in 1882. After her death, Tesla fell ill. He spent two to three weeks recuperating in Gospić and Tomingaj.

In 1896, according to an interview he gave in 1916, Tesla invented a type of loudspeaker. The sounds were of the quality of the telephones of that time. The invention was never patented nor released publicly (till years later by Tesla himself).

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Middle years

In 1884, leaving the warfare of his birthplace behind, Tesla moved to the United States of America to accept a job with the Edison Company in New York City. He arrived in the US with 4 cents to his name, a book of poetry, and a letter of recommendation (from Charles Batchelor, his manager in his previous job).

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Early employment

Tesla worked for Thomas Edison, who offered him $50,000 for improvements in Edison's DC dynamos. Tesla worked nearly a year to redesign them and, when inquired about the $50,000, Edison replied him, "Tesla, you don't understand our American humor." Tesla resigned. In 1886, Tesla formed his own company, Tesla Electric Light & Manufacturing. The initial financial investors disagreed with Tesla on his plan for an alternating current motor and eventually relieved him of his duties at the company. Tesla was unemployed for a time.

Tesla worked in New York as a common laborer from 1886 to 1887 to feed himself and raise capital for his next project. In 1887, he constructed the initial brushless alternate-current induction motor, which he demonstrated to the American Institute of Electrical Engineers (now IEEE) in 1888. Same year, he developed the principles of his Tesla coil and began working with Westinghouse, Westinghouse's Pittsburgh labs. Westinghouse listened to his ideas for polyphase systems which would allow transmision of AC electricity over large distances.

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X-rays and friendships

In April 1887, Tesla began investigating what would later be called X-rays using his own devices, which differed from other X-ray tubes in that they had no target electrode, as well as Crookes tubes. The modern term for this is the bremsstrahlung process.

In 1891, he became a naturalized American citizen and established his Houston Street laboratory in New York. He lit vacuum tubes wirelessly in it, providing evidence for the potential of wireless power transmission. Around this time, Tesla developed a close and lasting friendship with Mark Twain. They spent a lot of time together in Tesla's lab and elsewhere. Tesla's closest friends were artists. He also befriended R. A. Jonson, who adapted several Serbian poems of Jovan Jovanović Zmaj (which Tesla translated).

When he was 36 years old, the first patents concerning the polyphase power system were granted. He continued research of the system and rotating magnetic field principles. By 1892, Tesla became aware of what Wilhelm Röntgen later identified as effects of X-rays. He performed several experiments (including photographing the bones of his hand; later, he sent these images to Röntgen) but didn't make his findings widely known; much of his research was lost in the 1895 Houston Street lab fire.

Tesla was one of the first to report the hazards of working with x rays, but for the wrong reasons: "As to the hurtful actions on the skin... I note that they have been misinterpreted... They are not due to the Roentgen rays, but merely to the ozone generated in contact with the skin. Nitrous acid may also be responsible, but to a small extent." (Tesla, in Electrical Review, 30 November 1896)

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Wireless and the AIEE

Tesla served as the Vice-President of the American Institute of Electrical Engineers (now part of the IEEE) from 1892 to 1894. From 1893 to 1895, he investigated high frequency alternating currents. He generated AC of one million volts using a conical Tesla coil and investigated the skin effect in conductors, designed tuned circuits, invented a machine for inducing sleep, cordless gas discharge lamps, and transmitted electromagnetic energy without wires, effectively building the first radio transmitter.

In St. Louis, Missouri, Tesla made a demonstration related to radio communication (he demonstrated radio energy crossing space (one side of a stage to the other)) in 1893. Addressing the Franklin Institute in Philadelphia, Pennsylvania and the National Electric Light Association, he described and demonstrated in detail its principles. Heinrich Hertz had made such demonstrations, repeatedly, five years previously. Hertz' demonstrations were not public (they were conducted during his physics lectures) but strictly speaking neither were Tesla's (the Franklin Institute didn't open to the general public until 1934).

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World's Fair Exposition

At the 1893 World's Fair, the World Columbian Exposition in Chicago, Illinois, an international exposition was held which for the first time devoted a building to electrical exhibits. It was a historic event as Tesla and Westinghouse introduced visitors to AC power by using it to illuminate Exposition.

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War of currents

In the "War of Currents" era in the late 1880s, Nikola Tesla and Thomas Edison became adversaries due to Edison's promotion of direct current (DC) for electric power distribution over the more efficient alternating current (AC) advocated by Tesla. See War of Currents for more details.

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1896-1899

When Tesla was 41 years old, he filed the first basic radio patent (No. US645576). A year later, he demonstrated a remote controlled boat to the US military, believing that the military would want things such as radio-guided torpedoes. These devices had an innovative coherer and a series of logic gates. Radio remote control remained a novelty until the Space Age. Same year, Tesla devised an electric igniter for gasoline engines which was nearly identical to ideas about the same process used by modern internal combustion engines.

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Colorado Springs

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Moving in

In 1899, Tesla decided to move and began research in Colorado Springs, Colorado, where he could have room for his high-voltage high-frequency experiments. He chose this location primarily because of the frequent thunderstorms, the high altitude (where the air, being at a lower pressure, had a lower dielectric breakdown strength, making it easier to ionize), and the dryness of the air (minimizing leakage of electric charge through insulators). Also, the property was free and electric power available from the El Paso Power Company. Today, magnetic intensity charts also show that the ground around his lab possesses a denser magnetic field than surrounding area. Tesla reached Colorado Springs on May 17, 1899. Upon his arrival he told reporters that he was conducting experiments transmitting signals from Pikes Peak to Paris.

Tesla kept a diary of his experiments in the Colorado Springs lab where he spent nearly nine months. It consists of 500 pages of handwritten notes and nearly 200 drawings, recorded chronologically between June 1, 1899 and January 7, 1900, as the work occured, containing explanations of his experiments. He was developing a system for wireless telegraphy, telephony and the transmission of power, experimented with high-voltage electricity and the possibility of wireless transmitting and distributing large amounts of electrical energy over long distances. He also conceived a system for geophysical exploration--seismology--which he called telegeodynamics, based on his reciprocating mechanical oscillator patented in 1894, and explained that a long sequence of small explosions could be used to find ore and create earthquakes large enough to destroy the Earth. He did not experiment with this as he felt there would not be "a desirable outcome".

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Laboratory construction

Tesla, a local contractor, and several assistants commenced the construction of the laboratory shortly after arriving in Colorado Springs. The lab was established on Knob Hill, east of the Colorado School for the Deaf and Blind and one mile east of downtown. Its primary purpose were experiments with high frequency electricity and other phenomena, and secondary--research into wireless transmission of electrical power.

Tesla's design of the lab was a building fifty feet by sixty feet with eighty-foot ceilings. A one-hundred-forty-two foot conducting aerial with a thirty-inch copper-foil-covered wooden ball was erected on the roof. The roof was rolled back to prevent fire from sparks and other dangerous effects of the experiments. The laboratory had sensitive instruments and equipment.

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Magnifying transmitter

The lab possessed the largest Tesla Coil ever built (fifty-two feet in diameter), known as the Magnifying Transmitter (further MT). Not identical to a classic Tesla Coil, it was a three-coil magnifying system requiring different forms of analysis than lumped-constant coupled resonant coils presently described to most. It resonated at a natural quarter wavelength frequency and could work in a continuous-wave mode and in a partially damped-wave resonant mode. According to accounts, Tesla used it to transmit tens of thousands of watts of power wirelessly; it could generate millions of volts of electricity and produce lightning bolts more than one-hundred feet (30.5 metres) long. Tesla posted a large fence around it with a sign "Keep Out - Great Danger".

Tesla became the first man to create electrical effects on the scale of lightning. The MT produced thunder which was heard as far away as Cripple Creek. People near the lab would observe sparks emitting from the ground to their feet and through their shoes. Some have observed electrical sparks from the fire hydrants (Tesla for a time grounded out to the plumbing of the city). The area around the laboratory would glow with a blue corona (similar to St. Elmo's Fire). One of Tesla's experiments with the MT destroyed Colorado Springs Electric Company's generator by backfeeding the city's power generators, and blacked out the city. The company denied Tesla further access to the backup generator's feed if he did not repair the primary generator at his own expense; it was working again in a few days.

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Tuned circuits

Tesla also constructed many smaller resonance transformers and discovered the concept of tuned electrical circuits. He also developed a number of coherers for separating and perceiving electromagnetic waves and designed rotating coherers which he used to detect the unique types of electromagnetic phenomenon he observed. They had a mechanism of geared wheels driven by a coiled spring-drive mechanism which rotated small glass cylinders. These experiments were the final stage of years of work on synchronized tuned electrical circuits.

These transceivers were constructed to demonstrate how signals could be "tuned in". Tesla logged in the diary on July 3, 1899 that a separate resonance transformer tuned to the same high frequency as a larger high-voltage resonance transformer would transceive energy from the larger coil, acting as a transmitter of wireless energy, which was used to confirm Tesla's patent for radio during later disputes in the courts. These air core high-frequency resonate coils were the predecessors of systems from radio to radar and medical magnetic resonance imaging devices.

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Propagation and resonance

On July 3, 1899, Tesla discovered terrestrial stationary waves within the earth. He demonstrated that the Earth behaves as a smooth polished conductor and possesses electrical vibrations. He experimented with waves characterized by a lack of vibration at points, between which areas of maximum vibration occur periodically. These standing waves were produced by confining waves within constructed conductive boundaries. Tesla demonstrated that the Earth could respond at predescribed frequencies of electrical vibrations. At this time, Tesla realized that it was possible to transceive power around the globe.

Tesla conducted experiments contributing to the understanding of electromagnetic propagation and the Earth's resonance. It is well documented (from various photos from the time) that he lit hundreds of lamps wirelessly at a distance of up to twenty-five miles (forty kilometres). He transmitted signals several miles and lit neon tubes conducting through the ground. He researched ways to utilize the ionosphere to transmit energy wirelessly over long distances. He transmitted extremely low frequencies through the earth and portions of the ionosphere, called the Kennelly-Heaviside layer, in his experiments. Tesla made mathematical calculations and computations based on his experiments and discovered that the resonant frequency of this area was approximately eight hertz. In the 1950s, researchers confirmed the resonant frequency was in this range.

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Cosmic waves

In the Colorado Springs lab, Tesla recorded what he concluded were extraterrestrial radio signals and announced his findings in some of the scientific journals of the time. His announcements and data were rejected by the scientific community who did not believe him. He notes measurements of repetitive signals from his receiver which are substantially different from the signals he had noted from storms and earth noise. Specifically, he later recalled that the signals appeared in groups of clicks 1, 2, 3, and 4 clicks together. He stated in the article "A Giant Eye to See Round the World", of Feburary 25, 1923, that:

"Twenty-two years ago, while experimenting in Colorado with a wireless power plant, I obtained extraordinary experimental evidence of the existence of life on Mars. I had perfected a wireless receiver of extraordinary sensitiveness, far beyond anything known, and I caught signals which I interpreted as meaning 1--2--3--4. I believe the Martians used numbers for communication because numbers are universal." Albany Telegram — February 25, 1923

Clearly, Tesla felt the signal groups originated on the planet Mars. In 1996 Corum and Corum published an analysis of Jovian plasma torus signals which indicate that there was a correspondence between the setting of Mars at Colorado Springs, and the cessation of signals from Jupiter in the summer of 1899 when Tesla was there. Further, analysis by the Corums indicate that Tesla's transceiver was sensitive in the 18 kHz gap in the Kennelly-Heaviside layer which would have allowed that reception from Jupiter. Therefore, there is evidence the signals Tesla noticed came from Jupiter, among other possible sources. Tesla spent the latter part of his life trying to signal Mars.

It is important to recognize that when he says he "recorded" these signals, it is meant that he wrote down the data and his impressions of what he had heard. He did release reports at the time. Tesla’s inital announcement of the existence of extraterrestrial radio signals was in 1899. In March of 1907, Tesla wrote about signaling to Mars in Harvard Magazine and how it was a problem of electrical engineering. Additional descriptions come from remembrances twenty years later. All this was met with resistance and disbelief by his contemporaries.

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Colorado departure

Tesla left Colorado Springs on January 7, 1900. The lab was torn down, broken up, and its contents sold to pay debts. The Colorado experiments prepared Tesla for his next project, the establishment of a wireless power transmission facility that would be known as Wardenclyffe.

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Wardenclyffe

Main article: Wardenclyffe Tower

In 1900, Tesla began planning the Wardenclyffe Tower facility. In June 1902, Tesla's lab operations were moved to Wardenclyffe from Houston Street. Of the 700-plus patents accumulated by Tesla, the most controversial today is his Wardenclyffe Tower. The tower was meant to be the start of a global system for wireless telecommunications and also intended as a demonstration of wireless electrical power distribution. The tower was finally dismantled for scrap during wartime. Newspapers of the time labeled Wardenclyffe "Tesla's million-dollar folly."

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Nobel rumors

Due to the fact that the Nobel Prize was awarded to Marconi for radio in 1909, it was believed that Tesla and Edison were to share the Nobel Prize of 1912 (or 1915; some accounts differ). Tesla's rumored nomination for the Nobel Prize in Physics was primarily for his experiments with tuned circuits using high-voltage high-frequency resonant transformers. It was possible that Tesla was told of the plans of the physics award committee and let it be known that he would not share the award with Edison.

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Later years

Prior to the First World War, Tesla looked overseas for investors to fund his research. When the war started, Tesla lost funding he was receiving from his European patents. Wardenclyffe Tower was also demolished towards the end of WWI. Tesla had predicted the relevant issues of the post-World War I environment (a war which theoretically ended) in a printed article (December 20, 1914). Tesla believed that the League of Nations was not a remedy for the times and issues. In 1915, Tesla filed a lawsuit against Marconi attempting, unsuccessfully, to obtain a court injunction against the claims of Marconi. Around 1916, Tesla filed for bankruptcy because he owed so much in back taxes. He was living in poverty.

Tesla started to exhibit pronounced symptoms of obsessive-compulsive disorder in the years following. He became obsessed with the number three. He often felt compelled to walk around a block three times before entering a building, demanded a stack of three folded cloth napkins beside his plate at every meal, etc. The nature of OCD was little understood at the time and no treatments were available, so his symptoms were considered by some to be evidence of partial insanity and this probably hurt what was left of his reputation. This obsessive-compulsive behavior may have originated from the observations over repeated polyphase systems in nature that Tesla researched.

At this time, he was staying at the Waldorf-Astoria, renting in an arrangement for deferred payments. In 1917, around the time that the Wardenclyffe Tower was demolished, Tesla received the highest engineering award from the IEEE, the Edison Medal. The irony of this honor was probably not lost on Tesla.

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Radar

Tesla, in August 1917, first established principles regarding frequency and power level for the first primitive radar units in 1934. In the 1917 The Electrical Experimenter, he stated the principles of modern military radar in detail. His study of high-voltage, high-frequency alternating current led to this development. He had formed the concept of using radio waves to detect objects at a distance.

Tesla stated,

"For instance, by their [standing electromagnetic waves] use we may produce at will, from a sending station, an electrical effect in any particular region of the globe; [with which] we may determine the relative position or course of a moving object, such as a vessel at sea, the distance traversed by the same, or its speed."

Tesla proposed to use electromagnetic waves to determine the relative position, speed, and course of a moving object and other modern concepts of radar. He had proposed it might help find submarines (which it isn't well-suited for), though it was first applied successfully to find aircraft (after their later proliferation) and surface ships during World War II. Emil Girardeau, working with the first French radar systems, stated he was building radar systems "conceived according to the principles stated by Tesla".

By the twenties, Tesla was reportedly negotiating with the United Kingdom government under Prime Minister Chamberlain about a ray system. Tesla had also stated that efforts had been made to steal the "death ray" (though they had failed). The Chamberlain government was removed, though, before any final negotiations occurred. The incoming Baldwin government found no use for Tesla's suggestions and ended negotiations.

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1930s

On Tesla's seventy-fifth birthday in 1931, Time magazine put him on its cover. The cover caption noted his contribution to electrical power generation. In 1935, many of Marconi's patents relating to the radio were declared invalid by the United States Court of Claims. The Court of Claims decided that the prior work of Tesla (specifically US645576 and US649621) had anticipated Marconi's later works. Tesla got his last patent in 1928 on January 3, an apparatus for aerial transportation which was the first instance of VTOL aircraft. In 1934, Tesla wrote to consul Janković of his homeland. The letter contained the message of gratitude to Mihajlo Pupin who initiated a donation scheme by which American companies could support Tesla. Tesla refused the assistance, and chose to live by a modest pension received from Yugoslavia and to continue researching.

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Dynamic theory of gravity

When he was eighty-one, Tesla challenged Albert Einstein's theory of relativity, announcing he was working on a dynamic theory of gravity and argued that a field of force was a better concept and did away with the curvature of space. Unfortunately the theory was never published, but Tesla may have been developing a theory about gravity waves. This theory provides a basis for plasma cosmology.

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Death and afterwards

Tesla died alone in the hotel New Yorker of heart failure, some time between the evening of January 5 and the morning of January 8, 1943. Despite selling his AC electricity patents, he was essentially destitute and died with significant debts.

At the time of his death, Tesla had been working on some form of teleforce weapon, or death ray, the secrets of which he had offered to the United States War Department on the morning of January 5. It appears that his proposed death ray was related to his research into ball lightning and plasma. He was found dead three days later and, after the FBI was contacted by the War Department, his papers were declared to be top secret.

Immediately after Tesla's death became known, the Federal Bureau of Investigation instructed the Office of Alien Property to take possession of his papers and property, despite his US citizenship. All of his personal effects were seized on the advice of presidential advisors. J. Edgar Hoover declared the case "most secret," because of the nature of Tesla's inventions and patents. Tesla's Serbian-Orthodox family and the Yugoslav embassy struggled with American authorities to gain these items after his death due to the potential significance of some of his research. Eventually, his nephew, Sava Kosanovich, got possession of some of his personal effects (which are now housed in the Nikola Tesla Museum in Belgrade, Yugoslavia). Tesla's funeral took place on January 12, 1943 at the Cathedral of Saint John the Divine in Manhattan, New York City.

Tesla always disputed the claim that Marconi invented radio. An ongoing lawsuit regarding this was finally resolved in Tesla's favor after his death. This decision was based on the fact that there was prior work existing before the establishment of Marconi's patent. At the time, the United States Army was involved in a patent infringement lawsuit with Marconi regarding radio, leading some to posit that the government granted Tesla the patent in order to nullify any claims Marconi would have to compensation (as, some posit, the government's initial granting to Marconi the patent right in order to nullify any claims Tesla had for compensation).

In 1976, a bronze statue of Tesla was placed at Niagara Falls.

Perhaps because of Tesla's personal eccentricity and the dramatic nature of his demonstrations, conspiracy theories about applications of his work persist. The common Hollywood stereotype of the "mad scientist" mirrors Tesla's real-life persona, or at least a caricature of it—which may be no accident considering that many of the earliest such movies (including the first movie version of Mary Shelley's Frankenstein) were produced by Tesla's old rival, Thomas Edison. There are at least two films describing Tesla's life. In the first, arranged for TV, Tesla was portrayed by Rade Šerbedžija. In 1980, Orson Welles produced a Yugoslavian film named Tajna Nikole Tesle (The Secret of Nikola Tesla).

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Views on war

Tesla believed that war could not be avoided until the cause for its recurrence was removed, but was opposed to wars in general. He possessed a hatred of war, from his parents and homeland, and sought to end warfare scientifically by devising protective measures that would prevent wars. He found exceptions and some justifiable situations where conflict was necessary. He envisioned wars of machines, not of humans, and of more terrible weapons in the future. He made the first of a race of robots which could carry out combat maneuvers. These weapons' destructive actions and ranges would have virtually no limit, he believed. He sought to reduce distance, such as in communication (for better understanding), transportation, and transmission of energy, as a means to insure friendly international relations.

Tesla's other solutions included the development of expedients for preventing any conflict. By the 1930s, he had developed what is known as a "Tesla shield", an electromagnetic shell which armaments could not penetrate. Tesla shields would transmit electrical energy without wires and produce destructive effects at a distance. A wireless transmitter, as described in the technical patent US1119732 (the Tesla coil), projected electrical energy (not necessarily destructive) in any amount to any distance and could be applied for innumerable purposes, both in peace and war.

A system for "Projecting Concentrated Non-Dispersive Energy Through Natural Media" known as teleforce was reportedly developed later in his life [commonly known as a "death ray" or "peace ray"] (primarily a defensive weapon, with characteristics of a weapon of offense). Teleforce was a type of defensive particle-beam weapon that would provide protection from invasion by enemies approaching by sea or air. Tesla could not find financing for demonstration of the "death ray" discoveries. The system's large dimensions naturally limited its use as an offensive weapon. Tesla also advocated developing wireless energy transmission and electrically powered airplanes.

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Education

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Association memberships

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Other honors

[[Image:Serbia100Dinara.jpg|thumb|right|222px|Tesla on 100 Serbian Dinars in 2004. Photo courtesy of tesla (symbol T) - compound derived SI unit of magnetic flux density.

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Quotations

See for Nikola Tesla's Quotations

"Tesla has contributed more to electrical science than any man up to his time." —Lord Kelvin
"[Tesla is] an eminent pioneer in the realm of high frequency currents... I congratulate [him] on the great successes of [his] life's work." —Albert Einstein
"The world, I think, will wait a long time for Nikola Tesla's equal in achievement and imagination." - Edwin H. Armstrong
"... all scientific men will be delighted to extend their warmest congratulations to Tesla and to express their appreciation of his great contributions to science." —Ernest Rutherford
"Tesla is entitled to the enduring gratitude of mankind." —Arthur Compton
"I am sending [Dr. Tesla]... my gratitude and my respect in overflowing measure." —Robert Millikan
"The evolution of electric power from the discovery of Faraday to the initial great installation of the Tesla polyphase system in 1896 is undoubtedly the most tremendous event in all engineering history." —Jonathan Zenneck
"We think of his contribution much oftener than that of Ampere and Ohm ... the induction motor and our power system are enduring monuments to Nikola Tesla." — Dr. E.F.W. Alexanderson
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See also

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References

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External links and resources









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