NICOLA TESLA
Autor: Luiz Candido | Publicado: 2011-04-07T15:16:00-07:00

 Nikola TeslaFrom Wikipedia, the free encyclopedia      Jump to: navigation,      search     
 Nikola Tesla 
 
circa 1890. 
 Born 10 July 1856(1856-07-10)
Smiljan, Austrian Empirea
(Croatian Military Frontier) 
 Died 7 January 1943(1943-01-07) (aged&nbsp;86)
New York City, New York, USA 
 Fields Mechanical and electrical engineering 
 Institutions Edison Machine Works
Tesla Electric Light &amp; Manufacturing
Westinghouse Electric &amp; Manufacturing Co. 
 Known&nbsp;for   &nbsp;[show]Tesla coil
Tesla turbine
Teleforce
Tesla's oscillator
Tesla electric car
Tesla principle
Tesla's Egg of Columbus
Alternating current
Induction motor
Rotating magnetic field
Wireless technology
Particle beam weapon
Death ray
Terrestrial stationary waves
Bifilar coil
Telegeodynamics
Electrogravitics
 
 Influences Ernst Mach 
 Influenced Gano Dunn 
 Notable awards Edison Medal (1916)
Elliott Cresson Medal (1893)
John Scott Medal (1934) 
 Signature
 
  Notes
a Austrian Empire (1804–1867) reorganized and renamed into Austria-Hungary (1867-1918) in 1867. 
Nikola Tesla (Serbian: Никола Тесла; 10 July 1856&nbsp;– 7 January 1943) was an inventor, mechanical engineer, and electrical engineer. He was an important contributor to the birth of commercial electricity, and is best known for his many revolutionary developments in the field of electromagnetism in the late 19th and early 20th centuries. Tesla's patents and theoretical work formed the basis of modern alternating current (AC) electric power systems, including the polyphase system of electrical distribution and the AC motor. This work helped usher in the Second Industrial Revolution.
Born an ethnic Serb in the village of Smiljan (now part of Gospić), in the Croatian Military Frontier[1] of the Austrian Empire (modern-day Croatia), Tesla was a subject of the Austrian Empire by birth and later became an American citizen.[2] Because of his 1894 demonstration of wireless communication through radio and as the eventual victor in the "War of Currents", he was widely respected as one of the greatest electrical engineers who worked in America.[3]  He pioneered modern electrical engineering and many of his discoveries  were of groundbreaking importance. In the United States during this  time, Tesla's fame rivaled that of any other inventor or scientist in  history or popular culture.[4] Tesla demonstrated wireless energy transfer  to power electronic devices as early as 1893, and aspired to  intercontinental wireless transmission of industrial power in his  unfinished Wardenclyffe Tower project.
Because of his eccentric personality and his seemingly unbelievable  and sometimes bizarre claims about possible scientific and technological  developments, Tesla was ultimately ostracized and regarded as a mad scientist by many late in his life.[5] Tesla died with little money at the age of 86 in a hotel suite in New York City.[6]
The SI unit measuring magnetic field B (also referred to as the magnetic flux density and magnetic induction), the tesla, was named in his honor (at the CGPM, Paris, 1960).

   Contents[hide]1 Early years 1.1 France and the United States

2 Middle years 2.1 American citizenship
2.2 Edison
2.3 Colorado Springs

3 Wardenclyffe years
4 Nobel prize and Tesla
5 Later years 5.1 Field theories
5.2 Directed-energy weapon
5.3 Theoretical inventions

6 Personal life 6.1 Death

7 Legacy and honors 7.1 Monuments
7.2 Portrayals in popular culture

8 See also
9 References 9.1 Notes
9.2 Sources
9.3 Further reading 9.3.1 Publications
9.3.2 Books
9.3.3 Journals
9.3.4 Filmography


10 External links
 
Early years   Nikola Tesla's birth house and statue in the village of Smiljan, Croatia  
  
  
  Nikola Tesla c.1879 at age 23, and his passport from 1883 
Tesla was born to Serbian parents in the village of Smiljan, Austrian Empire near the town of Gospić, in the territory of modern-day Croatia. His baptismal certificate reports that he was born on 28 June (N.S. 10 July), 1856, to Father Milutin Tesla, a priest in the Serbian Orthodox Church.[7] His paternal origin is thought to be either of one of the local Serb clans in the Tara valley or from the Herzegovinian noble Pavle Orlović.[8] His mother, Đuka, daughter of a Serbian Orthodox Church priest, came from a family domiciled in Lika and Banija, but with deeper origins to Kosovo. She was talented in making home craft tools and memorized many Serbian epic poems, but never learned to read.[9]
Nikola was the fourth of five children, having one older brother  (Dane, who was killed in a horse-riding accident when Nikola was five)  and three sisters (Milka, Angelina and Marica).[10] His family moved to Gospić in 1862. Tesla attended school at Higher Real Gymnasium in Karlovac.[11] He finished a four-year term in the span of three years.[12]
Tesla went on to study electrical engineering at the Austrian Polytechnic in Graz  (1875). While there, he studied the uses of alternating current. Some  sources say he received Baccalaureate degrees from the university at  Graz.[13][14][15]  However, the university says that he did not receive a degree and did  not continue beyond the first semester of his third year, during which  he stopped attending lectures.[16][17][18][19] In December 1878, Tesla left Graz and broke all relations with his family. His friends thought that he had drowned in the Mur River. He went to Marburg, (today's Maribor, in Slovenia), where he was first employed as an assistant engineer for a year. He suffered a nervous breakdown during this time. Tesla was later persuaded by his father to attend the Charles-Ferdinand University in Prague, which he attended for the summer term of 1880. Here, he was influenced by Ernst Mach. However, after his father died, he left the university, having completed only one term.[20]
Tesla engaged in reading many works, memorizing complete books, supposedly having a photographic memory.[21]  Tesla related in his autobiography that he experienced detailed moments  of inspiration. During his early life, Tesla was stricken with illness  time and time again. He suffered a peculiar affliction in which blinding  flashes of light would appear before his eyes, often accompanied by  visions. Much of the time the visions were linked to a word or idea he  might have come across, at other times they would provide the solution  to a particular problem he had been encountering; just by hearing the  name of an item, he would be able to envision it in realistic detail.  Modern-day synesthetes  report similar symptoms. Tesla would visualize an invention in his mind  with extreme precision, including all dimensions, before moving to the  construction stage; a technique sometimes known as picture thinking.  He typically did not make drawings by hand, instead just conceiving all  ideas with his mind. Tesla also often had flashbacks to events that had  happened previously in his life; these began during his childhood.[21]
In 1880, he moved to Budapest to work under Tivadar Puskás in a telegraph company,[22] the National Telephone Company.  There, he met Nebojša Petrović, a young, Serbian inventor who lived in  Austria. Although their encounter was brief, they did work on a project  together using twin turbines to create continual power. On the opening  of the telephone exchange  in Budapest, 1881, Tesla became the chief electrician to the company,  and was later engineer for the country's first telephone system. He also  developed a device that, according to some, was a telephone repeater or amplifier, but according to others could have been the first loudspeaker.[23]
   Drawing from U.S. Patent 381968, illustrating principle of alternating current motor inventionFrance and the United StatesIn 1882 he moved to Paris, to work as an engineer for the Continental Edison Company,  designing improvements to electric equipment brought overseas from  Edison's ideas. According to his autobiography, in the same year he  conceived the induction motor and began developing various devices that use rotating magnetic fields for which he received patents in 1888.
Soon thereafter, Tesla was awakened from a dream in which his mother had died.[24] After her death, Tesla fell ill. He spent two to three weeks recuperating in Gospić and the village of Tomingaj near Gračac, his mother's birthplace.
On 6 June 1884, Tesla first arrived in the United States, in New York City[25] with little besides a letter of recommendation from Charles Batchelor, a former employer. In the letter of recommendation to Thomas Edison,  it is claimed that Batchelor wrote, 'I know two great men and you are  one of them; the other is this young man', but the exact contents of the  letter is disputed in McNichol's book. Edison hired Tesla to work for  his Edison Machine Works. Tesla's work for Edison began with  simple electrical engineering and quickly progressed to solving some of  the company's most difficult problems. Tesla was even offered the task  of completely redesigning the Edison company's direct current generators.[26]
Tesla claimed he was offered US$50,000 (~ US$1.1&nbsp;million in 2007, adjusted for inflation)[27] if he redesigned Edison's inefficient motor and generators, making an improvement in both service and economy.[28] In 1885 when Tesla inquired about the payment for his work, Edison replied, "Tesla, you don't understand our American humor," thus breaking his word.[29][30]  Earning US$18 per week, Tesla would have had to work for 53 years to  earn the amount he was promised. The offer was equal to the initial  capital of the company. Tesla immediately resigned when he was refused a  raise to US$25 per week.[31]
Tesla, in need of work, eventually found himself digging ditches for a  short period of time for the Edison company. He used this time to focus  on his AC polyphase system.[32]
Middle years
      Wireless transmission of power and energy demonstration during his high frequency and potential lecture of 1891Electromechanical devices and principles developed by Nikola Tesla:  Various devices that use rotating magnetic fields (1882)
The Induction motor, rotary transformers, and "high" frequency alternators
The Tesla coil,[33] his magnifying transmitter, and other means for increasing the intensity of electrical oscillations (including condenser discharge transformations and the Tesla oscillators[34][35])
Alternating current long-distance electrical transmission system[36] (1888) and other methods and devices for power transmission
Systems for wireless communication (prior art for the invention of radio) and radio frequency oscillators[37]
Robotics and the electronic logic gate[38]
Electrotherapy Tesla currents[39][40][41]
Wireless transfer of electricity and the Tesla effect[42][43]
Tesla impedance phenonomena[44]
Tesla electro-static field
Tesla principle
Bifilar coil
Telegeodynamics
Tesla insulation
Tesla impulses[45]
Tesla frequencies[33]
Tesla discharge[33]
Forms of commutators and methods of regulating third brushes
Tesla turbines (e.g., bladeless turbines) for water, steam and gas and the Tesla pumps
Tesla igniter
Corona discharge ozone generator
Tesla compressor
X-rays Tubes using the Bremsstrahlung process
Devices for ionized gases and "Hot Saint Elmo's Fire".[46]
Devices for high field emission
Devices for charged particle beams
Phantom streaming devices[47]
Arc light systems
Methods for providing extremely low level of resistance to the passage of electric current (predecessor to superconductivity)
Voltage multiplication circuitry
Devices for high voltage discharges
Devices for lightning protection
VTOL aircraft
Dynamic theory of gravity
Concepts for electric vehicles
Polyphase systems
 
In 1886, Tesla formed his own company, Tesla Electric Light &amp; 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 worked in New York as a laborer from 1886 to 1887 to  feed himself and raise capital for his next project. In 1887, he  constructed the initial brushless alternating current induction motor, which he demonstrated to the American Institute of Electrical Engineers (now IEEE) in 1888. In the same year, he developed the principles of his Tesla coil, and began working with George Westinghouse at Westinghouse Electric &amp; Manufacturing Company's Pittsburgh  labs. Westinghouse listened to his ideas for polyphase systems which  would allow transmission of alternating current electricity over long  distances.
In April 1887, Tesla began investigating what would later be called X-rays using his own single terminal vacuum tubes (similar to his patent #514,170).  This device differed from other early X-ray tubes in that it had no  target electrode. The modern term for the phenomenon produced by this  device is bremsstrahlung (or braking radiation). We now know that this device operated by emitting electrons from the single electrode through a combination of field electron emission and thermionic emission. Once liberated, electrons are strongly repelled by the high electric field  near the electrode during negative voltage peaks from the oscillating  HV output of the Tesla Coil, generating X rays as they collide with the  glass envelope. He also used Geissler tubes. By 1892, Tesla became aware of the skin damage that Wilhelm Röntgen later identified as an effect of X rays.
In the early research, Tesla devised several experimental setups to  produce X-rays. Tesla held that, with his circuits, the "instrument will  [... enable one to] generate Roentgen rays of much greater power than obtainable with ordinary apparatus".[48]
He also commented on the hazards of working with his circuit and  single-node X-ray-producing devices. Of his many notes in the early  investigation of this phenomenon, he attributed the skin damage to  various causes. He believed early on that damage to the skin was not  caused by the Roentgen rays, but the ozone generated in contact with the skin, and to a lesser extent, nitrous acid. Tesla incorrectly held that x-rays were longitudinal waves, such as those produced in waves in plasma. There are known examples of this and these plasma waves can occur in the situation of force-free magnetic fields.[49][50] His hypotheses and experiments were confirmed by others.[51]
Tesla continued research in the field. He performed several  experiments prior to Roentgen's discovery (including photographing the  bones of his hand; later, he sent these images to Roentgen) but did not  make his findings widely known; much of his research was lost in the 5th  Avenue laboratory fire of March 1895.
Tesla demonstrated wireless energy transmission as early as 1891. The Tesla effect  is a term for an application of this type of electrical conduction  (that is, the movement of energy through space and matter, not just the  production of voltage across a conductor).[52][42]
American citizenshipOn 30 July 1891, he became a naturalized citizen of the United States at the age of 35. Tesla established his South Fifth Avenue laboratory in New York in the same year. Later, Tesla established his Houston Street laboratory in New York at 46 E. Houston Street.  He lit electric lamps wirelessly at both of the New York locations,  providing evidence for the potential of wireless power transmission.[53]
Some of Tesla's closest friends were artists. He befriended Century Magazine editor Robert Underwood Johnson, who adapted several Serbian poems of Jovan Jovanović Zmaj (which Tesla translated). Also during this time, Tesla was influenced by the Vedic philosophy (i.e., Hinduism) teachings of the Swami Vivekananda; so much so that, after his exposure to Hindu-Vedic thought, Tesla started using Sanskrit words to name some of his fundamental concepts regarding matter and energy.[54]
   Nikola Tesla's AC dynamo used to generate AC which is used to transport electricity across great distances. It is contained in U.S. Patent 390,721.When Tesla 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. Tesla served, from 1892 to  1894, as the vice president of the American Institute of Electrical Engineers, the forerunner (along with the Institute of Radio Engineers) of the modern-day IEEE. 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, building the first radio transmitter. In St. Louis, Missouri, Tesla made a demonstration related to radio communication in 1893. Addressing the Franklin Institute in Philadelphia, Pennsylvania and the National Electric Light Association,  he described and demonstrated in detail its principles. Tesla's  demonstrations were written about widely through various media outlets.  Tesla also investigated harvesting energy that is present throughout space.  He believed that it was merely a question of time when men would  succeed in attaching their machinery to the very wheelwork of nature,  stating: "Ere many generations pass, our machinery will be driven by a  power obtainable at any point of the universe."[55]
At the 1893 World's Fair, the World's Columbian Exposition  in Chicago, an international exposition was held which, for the first  time, devoted a building to electrical exhibits. It was a historic event  as Tesla and George Westinghouse introduced visitors to AC power by using it to illuminate the Exposition. On display were Tesla's fluorescent lamps and single node bulbs. An observer noted:
 Within the room was suspended two hard-rubber plates covered with  tin foil. These were about fifteen feet apart, and served as terminals  of the wires leading from the transformers. When the current was turned  on, the lamps or tubes, which had no wires connected to them, but lay on  a table between the suspended plates, or which might be held in the  hand in almost any part of the room, were made luminous. These were the  same experiments and the same apparatus shown by Tesla in London about  two years previous, "where they produced so much wonder and  astonishment".[56]Tesla also explained the principles of the rotating magnetic field and induction motor by demonstrating how to make an egg made of copper stand on end in his demonstration of the device he constructed known as the "Egg of Columbus".
The Tesla generator was developed by Tesla in 1895, in conjunction with his developments concerning the liquefaction  of air. Tesla knew, from Lord Kelvin's discoveries, that more heat is  absorbed by liquefied air when it is re-gasified and used to drive  something, than is required by theory; in other words, that the  liquefaction process is somewhat anomalous or 'over unity'.[57]  Just prior to Tesla's completion of his work and the filing of a patent  application, Tesla's laboratory burned down, destroying all his  equipment, models and inventions. Immediately after the fire, Carl von Linde, in Germany, filed a patent application for the same process.[58]
A "world system" for "the transmission of electrical energy without wires" that depends upon the electrical conductivity  of the earth was proposed, in which transmission in various natural  media with current that passes between the two points are used to power  devices. In a practical wireless energy transmission system using this  principle, a high-power ultraviolet beam might be used to form a  vertical ionized channel in the air directly above the  transmitter-receiver stations. The same concept is used in virtual lightning rods, the electrolaser electroshock weapon,[59] and has been proposed for disabling vehicles.
EdisonAlso in the late 1880s, Tesla and Thomas Edison became adversaries in part because of Edison's promotion of direct current (DC) for electric power  distribution over the more efficient alternating current advocated by  Tesla and Westinghouse. Until Tesla invented the induction motor, AC's  advantages for long distance high voltage transmission were counterbalanced by the inability to operate motors on AC. As a result of the "War of Currents",  Edison and Westinghouse went nearly bankrupt, so in 1897, Tesla  released Westinghouse from contract, providing Westinghouse a break from  Tesla's patent royalties. Also in 1897, Tesla researched radiation, which led to setting up the basic formulation of cosmic rays.[60]
In 1897, at age 41, Tesla filed the first radio patent (U.S. Patent 645,576). A year later, he demonstrated a radio-controlled boat to the US military, believing that the military would want things such as radio-controlled torpedoes. Tesla claimed to have developed the "Art of Telautomatics", a form of robotics, as well as the technology of remote control.[61] In 1898, he demonstrated a radio-controlled boat to the public during an electrical exhibition at Madison Square Garden. Tesla called his boat a "teleautomaton".[62] In the same year, Tesla devised an "electric igniter" or spark plug for Internal combustion gasoline engines. He gained U.S. Patent 609,250, "Electrical Igniter for Gas Engines", on this mechanical ignition system.  Tesla lived in the former Gerlach Hotel, renamed The Radio Wave  building, at 49 W 27th St. (between Broadway and Sixth Avenue), Lower Manhattan, before the end of the century where he conducted the radio wave experiments. A commemorative plaque was placed on the building in 1977 to honor his work. Remote radio control remained a novelty until WWI and afterward, when a number of countries used it in military programs.
Colorado SpringsSee also: Magnifying transmitter   Publicity picture of a participant sitting in his laboratory in Colorado Springs with his "Magnifying transmitter" generating millions of volts. The arcs are about 7&nbsp;meters (23&nbsp;ft) long. (Tesla's notes identify this as a multiple exposure photograph.)   An experiment in Colorado Springs. This bank of lights is receiving  power by means of electrodynamic induction from a nearby transmitter   A Colorado Springs experiment: here a grounded tuned coil in resonance with a distant transmitter illuminates a light near the bottom of the picture.In 1899, Tesla decided to move and began research in Colorado Springs, Colorado in a lab located near Foote Ave. and Kiowa St.,[63]  where he would have room for his high-voltage, high-frequency  experiments. Upon his arrival he told reporters that he was conducting wireless telegraphy experiments transmitting signals from Pikes Peak to Paris. Tesla's diary contains explanations of his experiments concerning the ionosphere and the ground's telluric currents via transverse waves and longitudinal waves.[64] At his lab, Tesla proved that the earth was a conductor, and he produced artificial lightning (with discharges consisting of millions of volts, and up to 135&nbsp;feet long).[65] Tesla also investigated atmospheric electricity,  observing lightning signals via his receivers. Reproductions of Tesla's  receivers and coherer circuits show an unpredicted level of complexity  (e.g., distributed high-Q helical resonators, radio frequency feedback, crude heterodyne effects, and regeneration techniques).[66] Tesla stated that he observed stationary waves during this time.[67]
Tesla researched ways to transmit power and energy wirelessly over  long distances (via transverse waves, to a lesser extent, and, more  readily, longitudinal waves). He transmitted extremely low frequencies through the ground as well as between the Earth's surface and the Kennelly–Heaviside layer.  He received patents on wireless transceivers that developed standing  waves by this method. In his experiments, he made mathematical  calculations and computations based on his experiments and discovered  that the resonant frequency  of the Earth was approximately 8 hertz (Hz). In the 1950s, researchers  confirmed that the resonant frequency of the Earth's ionospheric cavity  was in this range (later named the Schumann resonance).
In Colorado Springs Tesla carried out various long distance wireless transmission-reception experiments. Tesla effect  is the application of a type of electrical conduction (that is, the  movement of energy through space and matter; not just the production of  voltage across a conductor). Through longitudinal waves,  Tesla transferred energy to receiving devices. He sent electrostatic  forces through natural media across a conductor situated in the changing  magnetic flux and transferred electrical energy to a wireless receiver.
In the Colorado Springs lab, Tesla observed unusual signals that he later thought may have been evidence of extraterrestrial radio wave communications coming from Venus or Mars.[68]  He noticed repetitive signals from his receiver which were  substantially different from the signals he had noted from storms and  earth noise. Specifically, he later recalled that the signals appeared  in groups of one, two, three, and four clicks together. Tesla had  mentioned that he thought his inventions could be used to talk with  other planets. There have even been claims that he invented a "Teslascope"  for just such a purpose. It is debatable what type of signals Tesla  received or whether he picked up anything at all. Research has suggested  that Tesla may have had a misunderstanding of the new technology he was  working with,[69] or that the signals Tesla observed may have been non-terrestrial natural radio source such as the Jovian plasma torus signals.[70]
Tesla left Colorado Springs  on 7 January 1900. The lab was torn down ca. 1905 and its contents sold  to pay debts. The Colorado experiments prepared Tesla for the  establishment of the trans-Atlantic wireless telecommunications facility  known as Wardenclyffe.
Wardenclyffe yearsIn 1900, with US$150,000 (51% from J. Pierpont Morgan), Tesla began planning the Wardenclyffe Tower  facility. In June 1902, Tesla's lab operations were moved to  Wardenclyffe from Houston Street. The tower was dismantled for scrap  during World War I.[71] Newspapers of the time labeled Wardenclyffe "Tesla's million-dollar folly". In 1904, the US Patent Office reversed its decision and awarded Guglielmo Marconi  the patent for radio, and Tesla began his fight to re-acquire the radio  patent. On his 50th birthday in 1906, Tesla demonstrated his 200&nbsp;hp (150&nbsp;kW) 16,000&nbsp;rpm bladeless turbine. During 1910–1911 at the Waterside Power Station in New York, several of his bladeless turbine engines were tested at 100–5000&nbsp;hp.
Nobel prize and TeslaSince the Nobel Prize in Physics was awarded to Marconi for radio in 1909, Thomas Edison and Tesla were mentioned in a press dispatch as potential laureates to share the Nobel Prize of 1915, leading to one of several Nobel Prize controversies.  Some sources have claimed that because of their animosity toward each  other neither was given the award, despite their scientific  contributions; that each sought to minimize the other's achievements and  right to win the award; that both refused to ever accept the award if  the other received it first; and that both rejected any possibility of  sharing it.[9][72]
In the years after these rumors, neither Tesla nor Edison won the  Prize (although Edison did receive one of 38 possible bids in 1915, and  Tesla did receive one bid out of 38 in 1937).[73] Earlier, Tesla alone was rumored to have been nominated for the Nobel Prize of 1912.  The rumored nomination was primarily for his experiments with tuned  circuits using high-voltage high-frequency resonant transformers.
Later yearsIn 1915, Tesla filed a lawsuit against Marconi attempting,  unsuccessfully, to obtain a court injunction against Marconi's claims.  After Wardenclyffe, Tesla built the Telefunken  Wireless Station in Sayville, Long Island. Some of what he wanted to  achieve at Wardenclyffe was accomplished with the Telefunken Wireless.  In 1917, the facility was seized and torn down by the Marines, because it was suspected that it could be used by German spies.
   The Wardenclyffe Tower facilityBefore World War I,  Tesla looked overseas for investors to fund his research. When the war  started, Tesla lost the funding he was receiving from his patents in  European countries. After the war ended, Tesla made predictions  regarding the relevant issues of the post-World War I environment, in a  printed article (20 December 1914). Tesla believed that the League of Nations was not a remedy for the times and issues. 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 undoubtedly hurt  what was left of his reputation.
At this time, he was staying at The Waldorf-Astoria Hotel, renting in an arrangement for deferred payments. Eventually, the Wardenclyffe deed was turned over to George Boldt,  proprietor of the Waldorf-Astoria, to pay a US$20,000 debt. In 1917,  around the time that the Wardenclyffe Tower was demolished by Boldt to  make the land a more viable real estate asset, Tesla received AIEE's highest honor, the Edison Medal.
Tesla, in August 1917, first established principles regarding frequency and power level for the first primitive radar units.[74]
In 1934, Émile Girardeau,  working with the first French radar systems, stated he was building  them "according to the principles stated by Tesla". By the 1920s, Tesla  was reportedly negotiating with the United Kingdom government about a  ray system. Tesla had also stated that efforts had been made to steal  the so called "death ray". It is suggested that the removal of the Chamberlain government ended negotiations.
On Tesla's 75th birthday in 1931, Time magazine put him on its cover. The cover caption noted his contribution to electrical power generation. Tesla received his last patent in 1928 for an apparatus for aerial transportation which was the first instance of VTOL aircraft. By the end of 1931, Tesla released "On Future Motive Power" which covered an ocean thermal energy conversion system. In 1934, Tesla wrote to consul Janković of his homeland. The letter contained a message of gratitude to Mihajlo Pupin  who had initiated a donation scheme by which American companies could  support Tesla. Tesla refused the assistance, choosing instead to live on  a modest pension received from Yugoslavia, and to continue his  research.
In 1936, Tesla wrote in a telegram to Vladko Maček: "I'm equally proud of my Serbian origin and my Croatian homeland. Long live all Yugoslavs."
Field theoriesWhen he was 81, Tesla stated he had completed a "dynamic theory of  gravity". He stated that it was "worked out in all details" and that he  hoped to soon give it to the world.[75] The theory was never published.
The bulk of the theory was developed between 1892 and 1894, during  the period that he was conducting experiments with high frequency and  high potential electromagnetism and patenting devices for their use. Reminiscent of Mach's principle, Tesla stated in 1925 that:
   Nikola Tesla, with Ruđer Bošković's book Theoria Philosophiae Naturalis, sits in front of the spiral coil of his high-frequency transformer at East Houston Street, New York. There is no thing endowed with life—from man, who is enslaving the  elements, to the nimblest creature—in all this world that does not sway  in its turn. Whenever action is born from force, though it be  infinitesimal, the cosmic balance is upset and the universal motion  results.
Tesla was critical of Einstein's relativity work, calling it:
 ...[a] magnificent mathematical garb which fascinates, dazzles and  makes people blind to the underlying errors. The theory is like a beggar  clothed in purple whom ignorant people take for a king&nbsp;... its  exponents are brilliant men but they are metaphysicists rather than  scientists&nbsp;...[76]
Tesla also argued:
 I hold that space cannot be curved, for the simple reason that it can  have no properties. It might as well be said that God has properties.  He has not, but only attributes and these are of our own making. Of  properties we can only speak when dealing with matter filling the space.  To say that in the presence of large bodies space becomes curved is  equivalent to stating that something can act upon nothing. I, for one,  refuse to subscribe to such a view.[77]
Tesla also believed that much of Albert Einstein's relativity theory had already been proposed by Ruđer Bošković, stating in an unpublished interview:
 ...the relativity theory, by the way, is much older than its present  proponents. It was advanced over 200 years ago by my illustrious  countryman Ruđer Bošković, the great philosopher, who, not withstanding  other and multifold obligations, wrote a thousand volumes of excellent  literature on a vast variety of subjects. Bošković dealt with  relativity, including the so-called time-space continuum&nbsp;...'.[78]
Directed-energy weaponLater in life, Tesla made remarkable claims concerning a "teleforce" weapon.[79] The press called it a "peace ray" or death ray.[80][81] In total, the components and methods included:[82][83]
An apparatus for producing manifestations of energy in free air instead of in a high vacuum as in the past. This, according to Tesla in 1934, was accomplished.
A mechanism for generating tremendous electrical force. This, according to Tesla, was also accomplished.
A means of intensifying and amplifying the force developed by the second mechanism.
A new method for producing a tremendous electrical repelling force. This would be the projector, or gun, of the invention.
Tesla worked on plans for a directed-energy weapon from the early 1900s until his death. In 1937, Tesla wrote a treatise entitled "The Art of Projecting Concentrated Non-dispersive Energy through the Natural Media", which concerned charged particle beams.[84] Tesla published the document in an attempt to expound on the technical description of a "superweapon that would put an end to all war." This treatise describing the particle beam is currently in the Nikola Tesla Museum archive in Belgrade.  It describes an open-ended vacuum tube with a gas jet seal that allows  particles to exit, a method of charging particles to millions of volts,  and a method of creating and directing nondispersive particle streams  (through electrostatic repulsion).[84]
His records indicate that the device is based on a narrow stream of atomic clusters of liquid mercury or tungsten accelerated via high voltage (by means akin to his magnifying transformer). Tesla gives the following description concerning the particle gun's operation:
 [The nozzle would] send concentrated beams of particles through the  free air, of such tremendous energy that they will bring down a fleet of  10,000 enemy airplanes at a distance of 200 miles from a defending  nation's border and will cause armies to drop dead in their tracks.[85]
The weapon could be used against ground based infantry or for antiaircraft purposes.[86] Tesla tried to interest the US War Department in the device.[87] He also offered this invention to European countries.[88] None of the governments purchased a contract to build the device. He was unable to act on his plans.[89]
Theoretical inventionsAnother of Tesla's theorized inventions is commonly referred to as Tesla's Flying Machine, which appears to resemble an ion-propelled aircraft.[90]  Tesla claimed that one of his life goals was to create a flying machine  that would run without the use of an airplane engine, wings, ailerons, propellers,  or an onboard fuel source. Initially, Tesla pondered about the idea of a  flying craft that would fly using an electric motor powered by grounded  base stations. As time progressed, Tesla suggested that perhaps such an  aircraft could be run entirely electro-mechanically. The theorized  appearance would typically take the form of a cigar or saucer.[91]
Personal life   Tesla's father Milutin TeslaTesla was fluent in eight languages. Along with Serbian, he spoke Czech, English, French, German, Hungarian, Italian, and Latin.[92]
Tesla may have suffered from obsessive-compulsive disorder, and had many unusual quirks and phobias.  He did things in threes, and was adamant about staying in a hotel room  with a number divisible by three. Tesla was physically revolted by  jewelry, notably pearl earrings.[93] He was fastidious about cleanliness and hygiene, and was by all accounts mysophobic.
Tesla was obsessed with pigeons, ordering special seeds for the pigeons he fed in Central Park  and even bringing injured ones into his hotel room to nurse them back  to health. Tesla was an animal-lover, often reflecting contentedly about  a childhood cat, "The Magnificent Mačak." Tesla never married. He was celibate and claimed that his chastity was very helpful to his scientific abilities.[21]  Nonetheless there have been numerous accounts of women vying for  Tesla's affection, even some madly in love with him. Tesla, though  polite, behaved rather ambivalently to these women in the romantic  sense.
Tesla was prone to alienating himself and was generally soft-spoken.  However, when he did engage in a social life, many people spoke very  positively and admiringly of him. Robert Underwood Johnson described him  as attaining a "distinguished sweetness, sincerity, modesty,  refinement, generosity, and force." His loyal secretary, Dorothy  Skerrit, wrote: "his genial smile and nobility of bearing always denoted  the gentlemanly characteristics that were so ingrained in his soul."  Tesla's friend Hawthorne wrote that "seldom did one meet a scientist or  engineer who was also a poet, a philosopher, an appreciator of fine  music, a linguist, and a connoisseur of food and drink."
Nevertheless, Tesla displayed the occasional cruel streak; he openly  expressed his disgust for overweight people, once firing a secretary  because of her weight.[94]  He was quick to criticize others' clothing as well, on several  occasions directing a subordinate to go home and change her dress.[21]
Tesla was widely known for his great showmanship, presenting his  innovations and demonstrations to the public as an artform, almost like a  magician. This seems to conflict with his observed reclusiveness; Tesla  was a complicated figure. He refused to hold conventions without his  Tesla coil blasting electricity throughout the room, despite the  audience often being terrified, though he assured them everything was  perfectly safe.
   Mark Twain in Tesla's lab, early 1894In middle age, Tesla became close friends with Mark Twain. They spent a lot of time together in his lab and elsewhere.
Tesla remained bitter in the aftermath of his dispute with Edison. The day after Edison died the New York Times contained extensive coverage of Edison's life, with the only negative opinion coming from Tesla, who was quoted as saying:
 He had no hobby, cared for no sort of amusement of any kind and  lived in utter disregard of the most elementary rules of hygiene &nbsp;...  His method was inefficient in the extreme, for an immense ground had to  be covered to get anything at all unless blind chance intervened and, at  first, I was almost a sorry witness of his doings, knowing that just a  little theory and calculation would have saved him 90 percent of the  labor. But he had a veritable contempt for book learning and  mathematical knowledge, trusting himself entirely to his inventor's  instinct and practical American sense.[95]Shortly before he died, Edison said that his biggest mistake had been  in trying to develop direct current, rather than the superior  alternating current system that Tesla had put within his grasp.[96]
Tesla was good friends with Robert Underwood Johnson. He had amicable relations with Francis Marion Crawford, Stanford White, Fritz Lowenstein, George Scherff, and Kenneth Swezey. He ripped up a Westinghouse  contract that would have made him the world's first billionaire, in  part because of the implications it would have on his future vision of  free power, and in part because it would run Westinghouse out of  business, and Tesla had no desire to deal with the creditors.[citation needed]
Tesla lived the last ten years of his life in a two-room suite on the 33rd floor of the Hotel New Yorker,  room 3327. There, near the end of his life, Tesla showed signs of  encroaching senility, claiming to be visited by a specific white pigeon  daily. Several biographers note that Tesla viewed the death of the  pigeon as a "final blow" to himself and his work.
Tesla believed that war could not be avoided until the cause for its  recurrence was removed, but was opposed to wars in general. However,  Tesla came to find exceptions in which he thought certain situations and  wars were justifiable.[97]  Tesla sought to reduce distance, such as in communication for better  understanding, transportation, and transmission of energy, as a means to  ensure friendly international relations.[98]
Tesla was a life-long bachelor. Like many of his era, he became a proponent of a self-imposed selective breeding version of eugenics. In a 1937 interview, he stated:
 ... man's new sense of pity began to interfere with the ruthless  workings of nature. The only method compatible with our notions of  civilization and the race is to prevent the breeding of the unfit by  sterilization and the deliberate guidance of the mating instinct ....  The trend of opinion among eugenists is that we must make marriage more  difficult. Certainly no one who is not a desirable parent should be  permitted to produce progeny. A century from now it will no more occur  to a normal person to mate with a person eugenically unfit than to marry  a habitual criminal.[99]In 1926, Tesla commented on the ills of the social subservience of women and the struggle of women toward gender equality,  indicated that humanity's future would be run by "Queen Bees". He  believed that women would become the dominant sex in the future.[100]
In his later years Tesla became a vegetarian. In an article for Century Illustrated Magazine  he wrote: "It is certainly preferable to raise vegetables, and I think,  therefore, that vegetarianism is a commendable departure from the  established barbarous habit." Tesla argued that it is wrong to eat  uneconomic meat when large numbers of people are starving; he also  believed that plant food was "superior to [meat] in regard to both  mechanical and mental performance". He also argued that animal slaughter  was "wanton and cruel".[101]
In his final years he suffered from extreme sensitivity to light, sound and other influences.[102]
Death   Urn with Tesla's ashes, Nikola Tesla Museum, BelgradeTesla died of heart failure alone in room 3327 of the New Yorker Hotel, on 7 January 1943.[103] Despite having sold his AC electricity patents, Tesla died with significant debts. Later that year the US Supreme Court upheld Tesla's patent number 645576 in a ruling that served as the basis for patented radio technology in the United States.[104]
Tesla's funeral took place on 12 January 1943, at the Cathedral of Saint John the Divine in Manhattan, New York City.[105] His body was cremated and his ashes taken to Belgrade, Serbia, then-Yugoslavia in 1957. The urn was placed in the Nikola Tesla Museum in Belgrade.
   Bust of Tesla by Ivan Meštrović, 1952, in Zagreb, CroatiaSoon after his death Tesla's safe was opened by his nephew Sava  Kosanović. Shortly thereafter Tesla's papers and other property were  impounded by the United States' Alien Property Custodian office in Tesla's compound at the Manhattan Warehouse, even though he was a naturalized citizen.
Dr. John G. Trump was the main government official who went over  Tesla's secret papers after his death in 1943. At the time, Trump was a  well-known electrical engineer serving as a technical aide to the  National Defense Research Committee of the Office of Scientific Research  &amp; Development, Technical Aids, Div. 14, NTRC (predecessor agency to  the CIA's Office of Scientific Intelligence). Trump was also a  professor at M.I.T., and had his feelings hurt by Tesla's 1938 review  and critique of M.I.T.'s huge Van de Graaff generator with its two  thirty-foot towers and two 15-foot-diameter (4.6&nbsp;m) balls, mounted on  railroad tracks—which Tesla showed could be out-performed in both  voltage and current by one of his tiny coils about two feet tall.[106]  Trump was asked to participate in the examination of Tesla's papers at  the Manhattan Warehouse &amp; Storage Co. Trump reported afterwards that  no examination had been made of the vast amount of Tesla's property,  that had been in the basement of the New Yorker Hotel, ten years prior  to Tesla's death, or of any of his papers, except those in his immediate  possession at the time of his death. Trump concluded in his report,  that there was nothing that would constitute a hazard in unfriendly  hands.
At the time of his death, Tesla had been working on the Teleforce  weapon, or 'death ray,' that he had unsuccessfully marketed to the US  War Department. It appears that Teleforce was related to his research  into ball lightning and plasma, and was conceived as a particle beam weapon. The US government did not find a prototype of the device in the safe.
After the FBI was contacted by the War Department, his papers were declared to be top secret. The personal effects were sequestered on the advice of presidential advisers; J. Edgar Hoover declared the case most secret, because of the nature of Tesla's inventions and patents.[107]  One document stated that "[he] is reported to have some 80&nbsp;trunks in  different places containing transcripts and plans having to do with his  experiments [...]". Altogether, in Tesla's effects, there were the  contents of his safe, two truckloads of papers and apparati from his  hotel, another 75 packing crates and trunks in a storage facility, and  another 80 large storage trunks in another storage facility. The Navy  and several "federal officials" spent two days microfilming some of the  stuff at the Office of Alien Properties storage facility in 1943, and  that was it, until Oct., 1945.[108]
Tesla's family and the Yugoslav embassy struggled with the American  authorities to gain these items after his death because of the potential  significance of some of his research. Eventually Mr. Kosanović won  possession of the materials, which are now housed in the Nikola Tesla Museum.[109]
Legacy and honorsSee also: Nikola Tesla in popular culture   Nikola Tesla on contemporary 100 Serbian dinar bill.The tesla (symbol T) - compound derived SI unit of magnetic flux density.[110]
Tesla - a crater on the far side of the moon of 26 kilometers in diameter at -2,0° width, -132.0° height.[111]
2244 Tesla - a minor planet.[111]
TPP Nikola Tesla - the largest power plant in Serbia.
The rock band Tesla takes its name from Nikola Tesla.[112]
An electric car company, Tesla Motors, named their company in tribute to Tesla.[113]
The Belgrade Nikola Tesla Airport is named in his honor.[114]
Google honoured Tesla on his birthday on 10 July 2009 by displaying a doodle in the Google search home page, that showed the G as a tesla coil.[115][116]
MonumentsA monument to Tesla was established at Niagara Falls, New York. This monument, portraying Tesla reading a set of notes, is a copy of a monument standing in front of the University of Belgrade Faculty of Electrical Engineering. Another monument to Tesla, featuring him standing on a portion of an alternator, was established at Queen Victoria Park in Niagara Falls, Ontario, Canada.  The monument was officially unveiled on 9 July 2006 on the 150th  anniversary of Tesla's birth. The monument was sponsored by St. George  Serbian Church, Niagara Falls, and designed by Les Drysdale of Hamilton, Ontario. Drysdale's design was the winning design from an international competition.
In 1994, acting on the advice of the President's Advisory Council on  Historic Preservation, a formal nomination process was initiated by the Tesla Wardenclyffe Project  seeking placement of the Wardenclyffe laboratory-office building and  the Tesla tower foundation on both the New York State and National  Registers of Historic Places. This would result in the creation of a  monument to Tesla out of the Wardenclyffe site itself.[117]
Portrayals in popular cultureMain article: Nikola Tesla in popular cultureNikola Tesla has appeared in popular culture as a character in books,  films, radio, TV, music, live theatre, comics and video games. The lack  of recognition received by Tesla during his own lifetime has made him a  tragic and inspirational character well suited to dramatic fiction. The  impact of the technologies invented by Tesla is a recurring theme in  several types of science fiction.
See also 
  Electronics portal 
List of Tesla patents
Electrical Experimenter
Timeline of low-temperature technology
ReferencesNotes ^ Bock-Luna 2007, p. 53
^ "Electrical pioneer Tesla honoured". BBC News. 2006-07-10. http://news.bbc.co.uk/2/hi/europe/5167054.stm. Retrieved 2009-08-15.&nbsp;
^ "Nikola Tesla - electrical engineer and inventor". Serbian Unity Congress. Archived from the original on 2008-02-19. http://web.archive.org/web/20080219051318/http://www.serbianunity.net/people/tesla/index.html. Retrieved 2009-08-15.&nbsp;
^ Valone, Thomas (2002). Harnessing the Wheelwork of Nature: Tesla's Science of Energy. Adventures Unlimited Press. p.&nbsp;102. ISBN&nbsp;1931882045. http://books.google.com/?id=ZNqo1zaZRTYC&amp;printsec=frontcover&amp;dq=Harnessing+the+Wheelwork+of+Nature:+Tesla%27s+Science+of+Energy#v=onepage&amp;q&amp;f=false. Retrieved 21 November 2010.&nbsp;
^ Robert Lomas (1999-08-21). "Spark of genius". Independent Magazine. http://www.robertlomas.com/Tesla/Independent_Article.html. Retrieved 2008-07-29.&nbsp;
^ Bennett, Scott (2007). Encyclopedia of Energy. ISBN&nbsp;818994052X. http://books.google.com/?id=DZXhE38wOKoC&amp;pg=PT59&amp;dq=tesla+death+hotel+room+alone#v=onepage&amp;q=tesla%20death%20hotel%20room%20alone&amp;f=false. Retrieved 24 November 2010.&nbsp;
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^ Obrad Mićov Samardžić, "Porijeklo Samardžića i ostalih bratstava roda Orlovića", Mostar 1992.ISBN 86-82271-53-2.&nbsp;
^ a b Seifer 2001, p.&nbsp;7
^ Cheney, Uth &amp; Glenn 1999, p.&nbsp;3
^ O'Neill 2007, p.&nbsp;32
^ O'Neill 2007, p.&nbsp;33
^ Wysock, W.C.; J.F. Corum, J.M. Hardesty and K.L. Corum (22 October 2001). "Who Was The Real Dr. Nikola Tesla? (A Look At His Professional Credentials)" (PDF). Antenna Measurement Techniques Association, posterpape. http://www.teresonic.com/pdf/Who%20was%20the%20real%20Tesla.pdf.&nbsp;
^ "The Book of New York: Forty Years' Recollections of the American Metropolis" says he matriculated 4 degrees (physics, mathematics, mechanical engineering and electrical engineering)
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^ Nikola Tesla: the European Years, D. Mrkich
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^ Wohinz, Josef W. (Ed,) (2006). Nikola Tesla und die Technik in Graz. Graz, Austria: Verlag der Technischen Universität Graz. pp.&nbsp;&nbsp;16. ISBN&nbsp;3902465395.&nbsp;
^ Kulishich, Kosta (27 August 1931). "Tesla Nearly Missed His Career as Inventor: College Roommate Tells". Newark News.&nbsp;. Cited in Seifer, Marc, The Life and Times of Nikola Tesla, 1996
^ Seifer 2001, p.&nbsp;18
^ a b c d Cheney 2001, p.&nbsp;33
^ Wilson, James Grant; John Fiske (1901). Appleton's cyclopædia of American biography. p.&nbsp;261. http://books.google.com/?id=f6oLAAAAIAAJ&amp;pg=PA261&amp;dq=Appleton%27s+Cyclop%C3%A6dia+of+American+Biography+tesla#v=onepage&amp;q&amp;f=false. Retrieved 21 November 2010.&nbsp;
^ Klein, Maury (26 May 2009). The Power Makers: Steam, Electricity, and the Men Who Invented Modern America. Bloomsbury Press. ISBN&nbsp;159691677X. http://books.google.com/books?id=w0o5Ld53wAEC&amp;lpg=PT180&amp;dq=Did%20Tesla%20really%20invent%20the%20loudspeaker%3F&amp;pg=PT180#v=onepage&amp;q&amp;f=false. Retrieved 14 November 2010.&nbsp;
^ Seifer 2001, p.&nbsp;94
^ "Coming to America". Public Broadcasting Service. http://www.pbs.org/tesla/ll/ll_america.html. Retrieved 14 November 2010.&nbsp;
^ Carey, Charles W. (2002). American inventors, entrepreneurs &amp; business visionaries. Infobase Publishing. p.&nbsp;337. ISBN&nbsp;0816045593. http://books.google.com/?id=XKiGgl36bkgC. Retrieved 27 November 2010.&nbsp;
^ "Adjusting the reported given amount of money for inflation, the US$50,000 in 1885 would equal US$1,140,112.60 in 2007". Westegg.com. http://www.westegg.com/inflation/. Retrieved 2010-08-01.&nbsp;
^ Cheney 2001, pp.&nbsp;54&nbsp;– 57
^ Pickover, Clifford A. (1999). Strange brains and genius: the secret lives of eccentric scientists and madmen. Harper Perennial. p.&nbsp;14. ISBN&nbsp;0688168949. http://books.google.com/?id=P0CSxB2aHMcC&amp;printsec=frontcover&amp;dq=Strange+Brains+and+Genius:+The+Secret+Lives+of+Eccentric+Scientists+and+Madmen#v=onepage&amp;q&amp;f=false. Retrieved 17 November 2010.&nbsp;
^ O'Neill 2007, p.&nbsp;64
^ Jonnes 2004, p.&nbsp;110
^ Tesla 2000, p.&nbsp;17
^ a b c Houston, E. J. (1889). A dictionary of electrical words, terms and phrases. New York: W.J. Johnston. Page 956.
^  Routledge, R., &amp; Pepper, J. H. (1876). Discoveries and inventions  of the nineteenth century. London: G. Routledge and sons. Page&nbsp;545.
^ Archie Frederick Collins, Wireless Telegraphy: Its History, Theory and Practice. McGraw publishing company, 1905. Page 131
^  Tesla, Nikola, "A New System of Alternating Current Motors and  Transformers". American Institute of Electrical Engineers, May 1888.
^ Robert Routledge, Discoveries and Inventions of the Nineteenth Century. G. Routledge and Sons, 1903. Page 542.
^ "Tesla's invention of the electronic AND gate". 21st Century Books, Breckenridge, CO. (ed., this pertains to electronic logic gates in general; U.S. Patent 723,188 and U.S. Patent 725,605)
^ Institute of Electrical and Electronics Engineers, "The IEEE standard dictionary of electrical and electronics terms". 6th ed. New York, N.Y., Institute of Electrical and Electronics Engineers, c1997. IEEE Std 100-1996. ISBN 1-55937-833-6 [ed. Standards Coordinating Committee 10, Terms and Definitions; Jane Radatz, (chair)]
^  Dugan, William James, "Hand-book of electro-therapeutics". F.A.Davis  Company, 1910. Page&nbsp;123. "[...] speak of "Tesla currents" when we really  mean the high frequency currents."
^  Snow, William Benham, "Currents of high potential of high and other  frequencies". Scientific authors' publishing Co., 1918. Page&nbsp;121.
^ a b Norrie, H. S., "Induction Coils: How to make, use, and repair them".Norman H. Schneider, 1907, New York. 4th edition.
^ Electrical experimenter, January 1919. Page&nbsp;615
^ The Electrical engineer. (1884). London: Biggs &amp; Co. Page&nbsp;19
^ Bengt Anders Benson, Perseption apparatus for the Blind, U.S. Patent 3,250,023
^ Houston, E. J. (1889). A dictionary of electrical words, terms and phrases. New York: W.J. Johnston. Page&nbsp;801.
^ Houston, E. J. (1889). A dictionary of electrical words, terms and phrases. New York: W.J. Johnston. Page&nbsp;878.
^ N. Tesla, HIGH FREQUENCY OSCILLATORS FOR ELECTRO-THERAPEUTIC AND OTHER PURPOSES. Proceedings of the American Electro-Therapeutic Association, American Electro-Therapeutic Association. Page&nbsp;25.
^ Griffiths, David J. Introduction to Electrodynamics, ISBN 0-13-805326-X and Jackson, John D. Classical Electrodynamics, ISBN 0-471-30932-X.
^ Anonymous (1899). Transactions of the American Electro-therapeutic Association. p.&nbsp;16. http://books.google.com/?id=bUo7vYNkbKQC. Retrieved 25 November 2010.&nbsp;
^ Shrady, George Frederick; Stedman, Thomas Lathrop (1897). Medical record. p.&nbsp;287. http://books.google.com/?id=Jx4CAAAAYAAJ&amp;vq=tesla. Retrieved 25 November 2010.&nbsp;
^ Cheney 2001, p.&nbsp;174
^ Krumme, Katherine (2000) (pdf). Mark Twain and Nikola Tesla: Thunder and Lightning. University of California, Berkeley. http://www.nuc.berkeley.edu/dept/Courses/E-24/E-24Projects/Krumme1.pdf.&nbsp;
^ "THE INFLUENCE OF VEDIC PHILOSOPHY ON NIKOLA TESLA'S UNDERSTANDING OF FREE ENERGY". http://arizonaenergy.org/CommunityEnergy/INFLUENCE%20OF%20VEDIC%20ON%20TESLA%27S%20UNDERSTANDING%20OF%20FREE%20ENERGY.htm. Retrieved 27 November 2010.&nbsp;
^ Tesla, Nikola (1892). Experiments with alternate currents of high potential and high frequency. p.&nbsp;58. http://books.google.com/books?id=kNhCQPbYIsgC&amp;printsec=frontcover#v=onepage&amp;q&amp;f=false. Retrieved 26 November 2010.&nbsp;
^ Barrett, John Patrick (1894). Electricity  at the Columbian Exposition; Including an Account of the Exhibits in  the Electricity Building, the Power Plant in Machinery Hall. pp.&nbsp;268&nbsp;– 269. http://books.google.com/?id=CLtIAAAAMAAJ&amp;printsec=frontcover#v=onepage&amp;q&amp;f=false. Retrieved 29 November 2010.&nbsp;
^ Nikola Tesla, Startling Prediction of the World's Greatest Living Scientist (Article, the North American, 18 May 1902).
^ Pages 284-285, William R. Lyne, Pentagon Aliens, 1993.
^ A Survey of Laser Lightning Rod Techniques. Barnes, Arnold A., Jr.; Berthel, Robert O.
^ Waser, André, "Nikola Tesla’s Radiations and the Cosmic Rays".
^ Tesla, Nikola, "My Inventions", Electrical Experimenter magazine, Feb, June, and Oct, 1919. ISBN (also "The Strange Life of Nikola Tesla" at rastko.org)
^ Jonnes 2004, p.&nbsp;355
^ According to the Tesla memorial marker in Memorial park on Pikes Peak Ave.
^ Tesla, Nikola, "The True Wireless". Electrical Experimenter, May 1919. (also at pbs.org)
^ Gillispie, Charles Coulston, "Dictionary of Scientific Biography"; Tesla, Nikola. Charles Scribner's Sons, New York. ISBN
^ Corum, K. L., J. F. Corum, and A. H. Aidinejad, "Atmospheric Fields, Tesla's Receivers and Regenerative Detectors". 1994.
^ Corum, K. L., J. F. Corum, "Nikola Tesla, Lightning Observations, and Stationary Waves". 1994.
^ Tesla, Nikola, "Talking with Planets". Collier's Weekly, 19 February 1901. (EarlyRadioHistory.us)
^ Spencer, John (1991). The UFO Encyclopedia. New York: Avon Books. ISBN&nbsp;978-0-38-076887-5.&nbsp;
^ Corum, Kenneth L.; James F. Corum (1996). Nikola Tesla and the electrical signals of planetary origin. p.&nbsp;14. OCLC&nbsp;68193760.&nbsp;
^ Broad, William J. (4 May 2009). "A Battle to Preserve a Visionary’s Bold Failure". New York Times. http://www.nytimes.com/2009/05/05/science/05tesla.html?hp. Retrieved 2009-05-05.  "He eventually sold Wardenclyffe to satisfy $20,000 (today about  $400,000) in bills at the Waldorf. In 1917, the new owners had the giant  tower blown up and sold for scrap."&nbsp;
^ Research, Health (1996-09). Nikola Tesla Research. p.&nbsp;9. ISBN&nbsp;0787304042. http://books.google.com/?id=N0gD7HxMfsUC&amp;printsec=frontcover#v=onepage&amp;q&amp;f=false. Retrieved 28 November 2010.&nbsp;
^ Seifer 2001, pp.&nbsp;378&nbsp;– 380
^ Page, R.M., "The Early History of RADAR", Proceedings of the IRE, Volume 50, Number 5, May 1962, (special 50th Anniversary Issue).
^ Prepared Statement by Nikola Tesla downloadable from www.tesla.hu
^ New York Times, 11 July 1935, p&nbsp;23, c.8
^ New York Herald Tribune, 11 September 1932
^ 1936 unpublished interview, quoted in Anderson, L, ed. Nikola Tesla: Lecture Before the New York Academy of Sciences. 6 April 1897&nbsp;: The Streams of Lenard and Roentgen and Novel Apparatus for Their Production, reconstructed 1994
^ "Tesla's Ray". Time. 23 July 1934.&nbsp;
^ "Tesla, at 78, Bares New 'Death-Beam'". New York Times. 11 July 1934. http://select.nytimes.com/gst/abstract.html?res=FB0817FD3E5B107A93C3A8178CD85F408385F9.&nbsp;
^ "Tesla Invents Peace Ray". New York Sun. 10 July 1934.&nbsp;
^ "Death-Ray Machine Described". New York Sun. 11 July 1934.&nbsp;
^ "A Machine to End War". Feb. 1935.
^ a b Seifer 2001, p.&nbsp;454
^ "Beam to Kill Army at 200 Miles, Tesla's Claim on 78th Birthday". New York Times. 11 July 1934.&nbsp;
^ "'Death Ray' for Planes". New York Times. 22 September 1940.&nbsp;
^ "Aerial Defense 'Death-Beam' Offered to U. S. By Tesla" 12 July 1940
^ O'Neill, John J.. "Tesla Tries To Prevent World War II (unpublished Chapter 34 of Prodigal Genius)". PBS.&nbsp;
^ Velox, Particle beam weapon. everything2.com
^ Tesla, Nikola (1993). The fantastic inventions of Nikola Tesla. Adventures Unlimited Press. p.&nbsp;256. ISBN&nbsp;0932813194. http://books.google.com/books?id=fXB0fm-QqLMC. Retrieved 29 November 2010.&nbsp;
^ The Lost Journals of Nikola Tesla. by Tim Swartz. Inner Light – Global Communications (15 October 2000). Also see bibliotecapleyades.net
^ O'Neill 2007, p.&nbsp;282
^ Mast, Amy (PDF). America’s forgotten innovator, Nikola Tesla. Florida State University. pp. 14&nbsp;– 15. http://www.magnet.fsu.edu/mediacenter/publications/flux/vol1issue1/documents/magnetmilestones.pdf.&nbsp;
^ Cheney 2001, p.&nbsp;110
^ Thomas Edison: Life of an Electrifying Man. Biographiq. 2008. p.&nbsp;23. ISBN&nbsp;1599862166. http://books.google.com/books?id=LHHPo0vsdgMC&amp;printsec=frontcover#v=onepage&amp;q&amp;f=false. Retrieved 25 November 2010.&nbsp;
^ Cheney, Uth &amp; Glenn 1999, p.&nbsp;19
^ O'Neill 2007, p.&nbsp;238
^ "Giant Eye to See Round the World" Albany Telegram, 25 February 1923 (doc).
^ "A Machine to End War". Public Broadcasting Service. February 1937. http://www.pbs.org/tesla/res/res_art11.html. Retrieved 23 November 2010.&nbsp;
^ Kennedy, John B., "When woman is boss, An interview with Nikola Tesla". Colliers, 30 January 1926.
^ The century illustrated monthly magazine, Volume 60. 1900. p.&nbsp;180. http://books.google.com/?id=314iAQAAIAAJ&amp;pg=PA178&amp;dq=The+Problem+of+Increasing+Human+Energy#v=onepage&amp;q=The%20Problem%20of%20Increasing%20Human%20Energy&amp;f=false. Retrieved 21 November 2010.&nbsp;
^ Munson, Richard (2008). From Edison to Enron: The Business of Power and What It Means for the Future of Electricity. Praeger. p.&nbsp;37. ISBN&nbsp;027598740X. http://books.google.com/books?id=MNCea_BbzQcC&amp;printsec=frontcover#v=onepage&amp;q&amp;f=false. Retrieved 24 November 2010.&nbsp;
^ "Nikola  Tesla Dies. Prolific Inventor. Alternating Power Current's Developer  Found Dead in Hotel Suite Here. Claimed a 'Death Beam'. He Insisted the  Invention Could Annihilate an Army of 1,000,000 at Once.". New York Times. 8 January 1943, Friday. http://select.nytimes.com/gst/abstract.html?res=F10D13F93D59147B93CAA9178AD85F478485F9. Retrieved 2007-07-21.&nbsp;
^ U.S. Patent 645,576
^ Cheney, Uth &amp; Glenn 1999, p.&nbsp;158
^ Page 278, William R. Lyne, Pentagon Aliens, 1993
^ Hoover, John Edgar, et al.
^ Pages 278-279, William R. Lyne, Pentagon Aliens, 1993
^ "Nikola Tesla Museum". Tesla-museum.org. http://www.tesla-museum.org/. Retrieved 2010-08-01.&nbsp;
^ Seifer 2001, p.&nbsp;464
^ a b Schmadel, Lutz D. (2003). Dictionary of minor planet names. Springer. p.&nbsp;183. ISBN&nbsp;3540002383. http://books.google.com/?id=KWrB1jPCa8AC. Retrieved 28 November 2010.&nbsp;
^ Seifer 2001, p.&nbsp;468
^ "Why the Name "Tesla"?". Tesla Motors. Archived from the original on October 16, 2007. http://web.archive.org/web/20071016044752/http://www.teslamotors.com/learn_more/why_tesla.php. Retrieved 2008-06-10.&nbsp;
^ "Belgrade Nikola Tesla Airport". airport-desk.com. http://www.airport-desk.com/airports/europe/serbia/belgrade-nikola-tesla-airport.html. Retrieved 29 November 2010.&nbsp;
^ "Google Doodles: 2009 July - September". Google. http://www.google.com/logos/logos09-3.html. Retrieved 2011-01-09.&nbsp;
^ Wardrop, Murray (10 July 2009). "Nikola Tesla: Google commemorates birthday of pioneering electrical engineer". The Telegraph. http://www.telegraph.co.uk/technology/google/5793540/Nikola-Tesla-Google-commemorates-birthday-of-pioneering-electrical-engineer.html. Retrieved 28 November 2010.&nbsp;
^ "A MUSEUM AT WARDENCLYFFE The Creation of a Monument to Nikola TeslaT". Tesla Wardenclyffe Project, Inc.. http://www.tfcbooks.com/articles/monument.htm. Retrieved 2010-09-23.&nbsp;
Sources Seifer, Marc J (2001). Wizard: the life and times of Nikola Tesla&nbsp;: biography of a genius. Citadel. pp.&nbsp;542. ISBN&nbsp;0806519606. http://books.google.com/?id=h2DTNDFcC14C. Retrieved 14 November 2010.&nbsp;
O'Neill, John J (2007). Prodigal Genius: The Life of Nikola Tesla. Book Tree. pp.&nbsp;336. ISBN&nbsp;1602067430. http://books.google.com/?id=-cHJQL8qCEMC&amp;printsec=frontcover&amp;dq=Prodigal+Genius:+The+Life+of+Nikola+Tesla#v=onepage&amp;q&amp;f=false. Retrieved 14 November 2010.&nbsp;
Cheney, Margaret (2001) [1979]. Tesla: Man Out of Time. Simon and Schuster. ISBN&nbsp;0743215362. http://books.google.com/?id=ti2Jt7XarzMC. Retrieved 2007-06-17.&nbsp;
Cheney, Margaret; Uth, Robert; Glenn, Jim (1999). Tesla, Master of Lightning. Barnes &amp; Noble Books. pp.&nbsp;184. ISBN&nbsp;0760710058. http://books.google.com/?id=3W6_h6XG6VAC&amp;printsec=frontcover#v=onepage&amp;q&amp;f=false. Retrieved 22 November 2010.&nbsp;
Tesla, Nikola (2000). Childress, David Hatcher. ed. The Tesla Papers: Nikola Tesla on Free Energy &amp; Wireless Transmission of Power. Adventures Unlimited Press. pp.&nbsp;316. ISBN&nbsp;0932813860. http://books.google.com/?id=rwekkS3oD0EC&amp;printsec=frontcover#v=onepage&amp;q&amp;f=false. Retrieved 24 November 2010.&nbsp;
Jonnes, Jill (2004). Empires of Light: Edison, Tesla, Westinghouse, and the Race to Electrify the World. Random House Trade Paperbacks. pp.&nbsp;464. ISBN&nbsp;0375758844. http://books.google.com/?id=BKX5UYWzVyQC&amp;printsec=frontcover#v=onepage&amp;q&amp;f=false. Retrieved 25 November 2010.&nbsp;
Lomas, Robert, The Man who Invented the Twentieth Century. Lecture to South Western Branch of Instititute of Physics.
Martin, Thomas Commerford, The Inventions, Researches, and Writings of Nikola Tesla, New York: The Electrical Engineer, 1894 (3rd Ed.); reprinted by Barnes &amp; Noble, 1995 ISBN-X
Penner, John R.H. The Strange Life of Nikola Tesla, corrupted version of "My Inventions".
Pratt, H., Nikola Tesla 1856–1943, Proceedings of the IRE, Vol. 44, September, 1956.
Weisstein, Eric W., Tesla, Nikola (1856–1943). Eric Weisstein's World of Science.
Dimitrijevic, Milan S., Belgrade Astronomical Observatory Historical Review. Publ. Astron. Obs. Belgrade,), 162–170. Also, Srpski asteroidi, Tesla. Astronomski magazine.
Roguin, Ariel, Historical Note: Nikola Tesla: The man behind the magnetic field unit. J. Magn. Reson. Imaging 2004;19:369–374. © 2004 Wiley-Liss, Inc.
Sellon, J. L., The impact of Nikola Tesla on the cement industry.  Behrent Eng. Co., Wheat Ridge, CO. Cement Industry Technical  Conference. 1997. XXXIX Conference Record., 1997 IEEE/PC. Page(s)  125–133. ISBN
Valentinuzzi, M.E., Nikola Tesla: why was he so much resisted and forgotten?  Inst. de Bioingenieria, Univ. Nacional de Tucuman; Engineering in  Medicine and Biology Magazine, IEEE. July/August 1998, 17:4, pp.&nbsp;74–75.  ISSN
Secor, H. Winfield, Tesla's views on Electricity and the War, Electrical Experimenter, Volume 5, Number 4, August, 1917.
Florey, Glen, Tesla and the Military. Engineering 24, 5 December 2000.
Corum, K. L., J. F. Corum, Nikola Tesla, Lightning Observations, and Stationary Waves. 1994.
Corum, K. L., J. F. Corum, and A. H. Aidinejad, Atmospheric Fields, Tesla's Receivers and Regenerative Detectors. 1994.
Meyl, Konstantin, H. Weidner, E. Zentgraf, T. Senkel, T. Junker, and P. Winkels, Experiments to proof the evidence of scalar waves Tests with a Tesla reproduction. Institut für Gravitationsforschung (IGF), Am Heerbach 5, D-63857 Waldaschaff.
Anderson, L. I., John Stone Stone on Nikola Tesla’s Priority in Radio and Continuous Wave Radiofrequency Apparatus. The Antique Wireless Association Review, Vol. 1, 1986, pp.&nbsp;18–41.
Anderson, L. I., Priority in Invention of Radio, Tesla v. Marconi. Antique Wireless Association monograph, March 1980.
Marincic, A., and D. Budimir, Tesla's contribution to radiowave propagation.  Dept. of Electron. Eng., Belgrade Univ. (5th International Conference  on Telecommunications in Modern Satellite, Cable and Broadcasting  Service, 2001. TELSIKS 2001. pp.&nbsp;327–331 vol.1) ISBN-X
Page, R.M., The Early History of Radar, Proceedings of the IRE, Volume 50, Number 5, May, 1962, (special 50th Anniversary Issue).
C Mackechnie Jarvis Nikola Tesla and the induction motor. 1970 Phys. Educ. 5 280–287.
Giant Eye to See Round the World (DOC)
Toby Grotz, The Influence of Vedic Philosophy on Nikola Tesla's Understanding of Free Energy.
Bock-Luna, Birgit (2007). The past in exile: Serbian long-distance nationalism and identity in the wake of the Third Balkan War. LIT Verlag Münster. ISBN&nbsp;3825897524, 9783825897529.&nbsp;
Further readingPublications A New System of Alternating Current Motors and Transformers, American Institute of Electrical Engineers, May 1888.
Selected Tesla Writings, Scientific papers and articles written by Tesla and others, spanning the years 1888–1940.
Light Without Heat, The Manufacturer and Builder, January 1892, Vol. 24
Biography: Nikola Tesla, The Century Magazine, November 1893, Vol. 47
Tesla's Oscillator and Other Inventions, The Century Magazine, November 1894, Vol. 49
The New Telegraphy. Recent Experiments in Telegraphy with Sparks, The Century Magazine, November 1897, Vol. 55
BooksTesla, Nikola, "My Inventions"  Parts I through V published in the Electrical Experimenter monthly  magazine from February through June, 1919. Part VI published October,  1919. Reprint edition with introductory notes by Ben Johnson, New York:  Barnes and Noble,1982, ISBN; also online at Lucid Cafe, et cetera as My Inventions: The Autobiography of Nikola Tesla, 1919. ISBN
Martin, Thomas C., The Inventions, Researches, and Writings of Nikola Tesla, 1894 . ISBN-X
Auster, Paul, Moon Palace, 1989. Tells Tesla's story within the history of the United States.
Lomas, Robert, The Man Who Invented the Twentieth Century: Nikola Tesla, forgotten genius of electricity, 1999. ISBN
Childress, David H., The Fantastic Inventions of Nikola Tesla, 1993. ISBN
Glenn, Jim, The Complete Patents of Nikola Tesla, 1994. ISBN
Trinkaus, George TESLA: The Lost Inventions, High Voltage Press, 2002. ISBN 09-7096-182-0
Valone, Thomas, Harnessing the Wheelwork of Nature: Tesla's Science of Energy, 2002. ISBN
McNichol, Tom, AC/DC The Savage Tale of the First Standards War, Jossey-Bass 2006 ISBN 078798267-9
Journals Carlson, W. Bernard, "Inventor of dreams". Scientific American, March 2005 Vol. 292 Issue 3 p.&nbsp;78(7).
Jatras, Stella L., "The genius of Nikola Tesla". The New American, 28 July 2003 Vol. 19 Issue 15 p.&nbsp;9(1)
Rybak, James P., "Nikola Tesla: Scientific Savant". Popular Electronics, 1042170X, November 1999, Vol. 16, Issue 11.
Lawren, B., "Rediscovering Tesla". Omni, March 1988, Vol. 10 Issue 6.
FilmographySee also: Nikola Tesla in popular culture There are at least two films describing Tesla's life. In the first, filmed in 1977, arranged for TV, Tesla was portrayed by Rade Šerbedžija. In 1980, Orson Welles produced a Yugoslav film named Tajna Nikole Tesle (The Secret of Nikola Tesla), in which Welles himself played the part of Tesla's patron, J.P. Morgan. The film was directed by Krsto Papić, and Nikola Tesla was portrayed by Petar Božović.
"Tesla: Master of Lightning". 1999. ISBN (Book) ISBN (PBS Video)
Lost Lightning: The Missing Secrets of Nikola Tesla (at Google Video.) Tesla's designs for free energy and defensive weapons systems.
David Bowie portrayed Tesla in the 2006 film The Prestige.  Tesla's time in Colorado Springs was the focus of several scenes in the  film, which featured speculations on the explosive power of Tesla's  electrical experiments.
Tesla: Master of Lightning, produced by Robert Uth for New Voyage Communications in 2003, tapped Stacy Keach to supply the voice of Tesla.
External links
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The Nikola Tesla Museum
Nikola Tesla Niagara Falls Power
Tesla Resource Surrounding the PBS "Master of Lightning" documentary
World of Scientific Biography: Nikola Tesla, by Wolfram Research
Nikola Tesla Page
Tesla's grand-nephew William H. Terbo's site
Nikola Tesla, Forgotten American Scientist
Tesla Wardenclyffe Project, Long Island New York. Mission is the adaptive reuse of the Wardenclyffe laboratory building.
Nikola Tesla's Father: Milutin Tesla
Tesla: The European Years
Jim Bieberich's The Complete Nikola Tesla U.S. Patent Collection
Online archive of many of Tesla's writings, articles and published papers
Seifer, Marc J., and Michael Behar, Electric Mind, Wired Magazine, October 1998.
Works by Nikola Tesla at Project Gutenberg
Nikola Tesla's FBI file in pdf
Nikola Tesla Complete Patents in pdf
Kenneth M. Swezey Papers, 1891–1982, Archives Center, National Museum of American History, archival resources.
The Case Files of Nikola Tesla, Franklin Institute