Nikola Tesla ( ; ,"Tesla"
''

Random House Webster's Unabridged Dictionary ''Random House Webster's Unabridged Dictionary'' is a large American dictionary, first published in 1966 as ''The Random House Dictionary of the English Language: The Unabridged Edition''. Edited by Editor-in-chief Jess Stein, it contained 315, ...

''. ; 1856 – 7 January 1943) was a

Serbian-American Serbian Americans ( sr, / ) or American Serbs (), are Americans of Serb ethnic ancestry. As of 2013, there were about 190,000 American citizens who identified as having Serb ancestry. However, the number may be significantly higher, as there w ...

inventor An invention is a unique or novel device, method, composition, idea or process. An invention may be an improvement upon a machine, product, or process for increasing efficiency or lowering cost. It may also be an entirely new concept. If an ...

electrical engineer Electrical engineering is an engineering discipline concerned with the study, design, and application of equipment, devices, and systems which use electricity, electronics, and electromagnetism. It emerged as an identifiable occupation in the l ...

mechanical engineer Mechanical may refer to: Machine * Machine (mechanical), a system of mechanisms that shape the actuator input to achieve a specific application of output forces and movement * Mechanical calculator, a device used to perform the basic operations of ...

, and

futurist Futurists (also known as futurologists, prospectivists, foresight practitioners and horizon scanners) are people whose specialty or interest is futurology or the attempt to systematically explore predictions and possibilities abo ...

best known for his contributions to the design of the modern

alternating current Alternating current (AC) is an electric current which periodically reverses direction and changes its magnitude continuously with time in contrast to direct current (DC) which flows only in one direction. Alternating current is the form in whic ...

(AC) electricity supply system. Born and raised in the

Austrian Empire The Austrian Empire (german: link=no, Kaiserthum Oesterreich, modern spelling , ) was a Central- Eastern European multinational great power from 1804 to 1867, created by proclamation out of the realms of the Habsburgs. During its existence, ...

, Tesla studied engineering and physics in the 1870s without receiving a degree, gaining practical experience in the early 1880s working in

telephony Telephony ( ) is the field of technology involving the development, application, and deployment of telecommunication services for the purpose of electronic transmission of voice, fax, or data, between distant parties. The history of telephony is i ...

and at Continental Edison in the new

electric power industry The electric power industry covers the generation, transmission, distribution and sale of electric power to the general public and industry. The commodity sold is actually energy, not power, e.g. consumers pay for kilowatt-hours, power multip ...

. In 1884 he emigrated to the United States, where he became a naturalized citizen. He worked for a short time at the

Edison Machine Works The Edison Machine Works was a manufacturing company set up to produce dynamos, large electric motors, and other components of the electrical illumination system being built in the 1880s by Thomas A. Edison in New York City. History The need fo ...

in New York City before he struck out on his own. With the help of partners to finance and market his ideas, Tesla set up laboratories and companies in New York to develop a range of electrical and mechanical devices. His

(AC)

induction motor An induction motor or asynchronous motor is an AC electric motor in which the electric current in the rotor needed to produce torque is obtained by electromagnetic induction from the magnetic field of the stator winding. An induction motor ...

and related polyphase AC patents, licensed by

Westinghouse Electric The Westinghouse Electric Corporation was an American manufacturing company founded in 1886 by George Westinghouse. It was originally named "Westinghouse Electric & Manufacturing Company" and was renamed "Westinghouse Electric Corporation" in ...

in 1888, earned him a considerable amount of money and became the cornerstone of the polyphase system which that company eventually marketed. Attempting to develop inventions he could patent and market, Tesla conducted a range of experiments with mechanical oscillators/generators, electrical discharge tubes, and early X-ray imaging. He also built a wirelessly controlled boat, one of the first ever exhibited. Tesla became well known as an inventor and demonstrated his achievements to celebrities and wealthy patrons at his lab, and was noted for his showmanship at public lectures. Throughout the 1890s, Tesla pursued his ideas for wireless lighting and worldwide wireless electric power distribution in his high-voltage, high-frequency power experiments in New York and

Colorado Springs Colorado Springs is a home rule municipality in, and the county seat of, El Paso County, Colorado, United States. It is the largest city in El Paso County, with a population of 478,961 at the 2020 United States Census, a 15.02% increase since ...

. In 1893, he made pronouncements on the possibility of

wireless communication Wireless communication (or just wireless, when the context allows) is the transfer of information between two or more points without the use of an electrical conductor, optical fiber or other continuous guided medium for the transfer. The most ...

with his devices. Tesla tried to put these ideas to practical use in his unfinished

Wardenclyffe Tower Wardenclyffe Tower (1901–1917), also known as the Tesla Tower, was an early experimental wireless transmission station designed and built by Nikola Tesla on Long Island in 1901–1902, located in the village of Shoreham, New York. Tesla inten ...

project, an intercontinental wireless communication and power transmitter, but ran out of funding before he could complete it. After Wardenclyffe, Tesla experimented with a series of inventions in the 1910s and 1920s with varying degrees of success. Having spent most of his money, Tesla lived in a series of New York hotels, leaving behind unpaid bills. He died in New York City in January 1943. Tesla's work fell into relative obscurity following his death, until 1960, when the

General Conference on Weights and Measures The General Conference on Weights and Measures (GCWM; french: Conférence générale des poids et mesures, CGPM) is the supreme authority of the International Bureau of Weights and Measures (BIPM), the intergovernmental organization established i ...

named the

SI unit The International System of Units, known by the international abbreviation SI in all languages and sometimes pleonastically as the SI system, is the modern form of the metric system and the world's most widely used system of measurement. ...

magnetic flux density A magnetic field is a vector field that describes the magnetic influence on moving electric charges, electric currents, and magnetic materials. A moving charge in a magnetic field experiences a force perpendicular to its own velocity and to ...

the tesla in his honor. There has been a resurgence in popular interest in Tesla since the 1990s.

Early years

Nikola Tesla was born an ethnic

Serb The Serbs ( sr-Cyr, Срби, Srbi, ) are the most numerous South Slavic ethnic group native to the Balkans in Southeastern Europe, who share a common Serbian ancestry, culture, history and language. The majority of Serbs live in their na ...

in the village of Smiljan, within the Military Frontier, in the

(present day

Croatia , image_flag = Flag of Croatia.svg , image_coat = Coat of arms of Croatia.svg , anthem = " Lijepa naša domovino"("Our Beautiful Homeland") , image_map = , map_caption = , capi ...

), on 1856. His father, Milutin Tesla (1819–1879), was a priest of the

Eastern Orthodox Church The Eastern Orthodox Church, also called the Orthodox Church, is the second-largest Christian church, with approximately 220 million baptized members. It operates as a communion of autocephalous churches, each governed by its bishops via ...

. Tesla's mother, Đuka Mandić (1822–1892), whose father was also an

priest, had a talent for making home craft tools and mechanical appliances and the ability to memorize

Serbian epic poems Serbian epic poetry ( sr, Српске епске народне песме, Srpske epske narodne pesme) is a form of epic poetry created by Serbs originating in today's Serbia, Bosnia and Herzegovina, Croatia, Montenegro and North Macedonia ...

. Đuka had never received a formal education. Tesla credited his

eidetic memory Eidetic memory ( ; more commonly called photographic memory or total recall) is the ability to recall an image from memory with high precision—at least for a brief period of time—after seeing it only onceThe terms ''eidetic memory'' and ''pho ...

and creative abilities to his mother's genetics and influence. Tesla's progenitors were from western Serbia, near

Montenegro ) , image_map = Europe-Montenegro.svg , map_caption = , image_map2 = , capital = Podgorica , coordinates = , largest_city = capital , official_languages = ...

. Tesla was the fourth of five children. He had three sisters, Milka, Angelina, and Marica, and an older brother named Dane, who was killed in a horse riding accident when Tesla was aged five. In 1861, Tesla attended primary school in Smiljan where he studied German, arithmetic, and religion. In 1862, the Tesla family moved to the nearby

Gospić Gospić () is a town in the mountainous and sparsely populated region of Lika, Croatia. It is the administrative centre of Lika-Senj County. Gospić is located near the Lika River in the middle of a karst field ( Ličko Polje). Gospić is the ...

, where Tesla's father worked as parish priest. Nikola completed primary school, followed by middle school. In 1870, Tesla moved to

Karlovac Karlovac () is a city in central Croatia. According to the 2011 census, its population was 55,705. Karlovac is the administrative centre of Karlovac County. The city is located on the Zagreb-Rijeka highway and railway line, south-west of Zagre ...

to attend high school at the Higher Real Gymnasium where the classes were held in German, as it was usual throughout schools within the Austro-Hungarian Military Frontier. Milutin Tesla

Tesla later wrote that he became interested in demonstrations of electricity by his physics professor. Tesla noted that these demonstrations of this "mysterious phenomena" made him want "to know more of this wonderful force". Tesla was able to perform

integral calculus In mathematics, an integral assigns numbers to Function (mathematics), functions in a way that describes Displacement (geometry), displacement, area, volume, and other concepts that arise by combining infinitesimal data. The process of finding ...

in his head, which prompted his teachers to believe that he was cheating. He finished a four-year term in three years, graduating in 1873. After graduating Tesla returned to Smiljan but soon contracted

cholera Cholera is an infection of the small intestine by some strains of the bacterium '' Vibrio cholerae''. Symptoms may range from none, to mild, to severe. The classic symptom is large amounts of watery diarrhea that lasts a few days. Vomiting an ...

, was bedridden for nine months and was near death multiple times. In a moment of despair, Tesla's father (who had originally wanted him to enter the priesthood), promised to send him to the best engineering school if he recovered from the illness. The next year Tesla evaded

conscription Conscription (also called the draft in the United States) is the state-mandated enlistment of people in a national service, mainly a military service. Conscription dates back to Ancient history, antiquity and it continues in some countries to th ...

into the

Austro-Hungarian Army The Austro-Hungarian Army (, literally "Ground Forces of the Austro-Hungarians"; , literally "Imperial and Royal Army") was the ground force of the Austro-Hungarian Dual Monarchy from 1867 to 1918. It was composed of three parts: the joint arm ...

in Smiljan by running away southeast of Lika to

Tomingaj Tomingaj ( sr-cyr, Томингај) is a village in Croatia. Nikola Tesla Nikola Tesla ( ; ,"Tesla"
''

, near

Gračac Gračac (; ) is a town and municipality in the southern part of Lika, Croatia. The municipality is administratively part of Zadar County. Gračac is located south of Udbina, northeast of Obrovac, northwest of Knin and southeast of Gospić. S ...

. There he explored the mountains wearing hunter's garb. Tesla said that this contact with nature made him stronger, both physically and mentally. He read many books while in Tomingaj and later said that

Mark Twain Samuel Langhorne Clemens (November 30, 1835 – April 21, 1910), known by his pen name Mark Twain, was an American writer, humorist, entrepreneur, publisher, and lecturer. He was praised as the "greatest humorist the United States has pr ...

's works had helped him to miraculously recover from his earlier illness. He enrolled at the Imperial-Royal Technical College in Graz in 1875 on a Military Frontier scholarship. In his autobiography Tesla said he worked hard and earned the highest grades possible, passed nine exams (nearly twice as many as required) and received a letter of commendation from the dean of the technical faculty to his father, which stated, "Your son is a star of first rank." At Graz, Tesla noted his fascination with the detailed lectures on electricity presented by Professor Jakob Pöschl and described how he made suggestions on improving the design of an electric motor the professor was demonstrating. But by his third year he was failing in school and never graduated, leaving

Graz Graz (; sl, Gradec) is the capital city of the Austrian state of Styria and second-largest city in Austria after Vienna. As of 1 January 2021, it had a population of 331,562 (294,236 of whom had principal-residence status). In 2018, the popula ...

in December 1878. One biographer suggests Tesla wasn't studying and may have been expelled for gambling and womanizing. Tesla 1879 teslauniverse

Tesla's family did not hear from him after he left school. There was a rumor amongst his classmates that he had drowned in the nearby Mur River but in January one of them ran into Tesla in the town of

Maribor Maribor ( , , , ; also known by other historical names) is the second-largest city in Slovenia and the largest city of the traditional region of Lower Styria. It is also the seat of the City Municipality of Maribor, the seat of the Drava sta ...

across the border in

Slovenia Slovenia ( ; sl, Slovenija ), officially the Republic of Slovenia (Slovene: , abbr.: ''RS''), is a country in Central Europe. It is bordered by Italy to the west, Austria to the north, Hungary to the northeast, Croatia to the southeast, and ...

and reported that encounter to Tesla's family. It turned out Tesla had been working there as a draftsman for 60 florins per month. In March 1879, Milutin finally located his son and tried to convince him to return home and take up his education in Prague. Tesla returned to Gospić later that month when he was deported for not having a residence permit. Tesla's father died the next month, on 17 April 1879, at the age of 60 after an unspecified illness. During the rest of the year Tesla taught a large class of students in his old school in Gospić. In January 1880, two of Tesla's uncles put together enough money to help him leave Gospić for

Prague Prague ( ; cs, Praha ; german: Prag, ; la, Praga) is the capital and largest city in the Czech Republic, and the historical capital of Bohemia. On the Vltava river, Prague is home to about 1.3 million people. The city has a temperate ...

, where he was to study. He arrived too late to enroll at

Charles-Ferdinand University ) , image_name = Carolinum_Logo.svg , image_size = 200px , established = , type = Public, Ancient , budget = 8.9 billion CZK , rector = Milena Králíčková , faculty = 4,057 , administrative_staff = 4,026 , students = 51,438 , underg ...

; he had never studied

Greek Greek may refer to: Greece Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group. *Greek language, a branch of the Indo-European language family. **Proto-Greek language, the assumed last common ancestor ...

, a required subject; and he was illiterate in Czech, another required subject. Tesla did, however, attend lectures in philosophy at the university as an auditor but he did not receive grades for the courses.

Working at Budapest Telephone Exchange

Tesla moved to

Budapest Budapest (, ; ) is the capital and most populous city of Hungary. It is the ninth-largest city in the European Union by population within city limits and the second-largest city on the Danube river; the city has an estimated population o ...

Hungary Hungary ( hu, Magyarország ) is a landlocked country in Central Europe. Spanning of the Carpathian Basin, it is bordered by Slovakia to the north, Ukraine to the northeast, Romania to the east and southeast, Serbia to the south, Cr ...

, in 1881 to work under

Tivadar Puskás Tivadar Puskás de Ditró (in older English technical literature: Theodore Puskás) (17 September 1844 – 16 March 1893) was a Hungarian inventor, telephone pioneer, and inventor of the telephone exchange. He was also the founder of Telef ...

at a

telegraph Telegraphy is the long-distance transmission of messages where the sender uses symbolic codes, known to the recipient, rather than a physical exchange of an object bearing the message. Thus flag semaphore is a method of telegraphy, whereas ...

company, the Budapest Telephone Exchange. Upon arrival, Tesla realized that the company, then under construction, was not functional, so he worked as a draftsman in the Central Telegraph Office instead. Within a few months, the Budapest Telephone Exchange became functional, and Tesla was allocated the chief electrician position. During his employment, Tesla made many improvements to the Central Station equipment and claimed to have perfected a telephone

repeater In telecommunications, a repeater is an electronic device that receives a signal and retransmits it. Repeaters are used to extend transmissions so that the signal can cover longer distances or be received on the other side of an obstruction. Som ...

amplifier An amplifier, electronic amplifier or (informally) amp is an electronic device that can increase the magnitude of a signal (a time-varying voltage or current). It may increase the power significantly, or its main effect may be to boost t ...

, which was never patented nor publicly described.

Working at Edison

In 1882, Tivadar Puskás got Tesla another job in

Paris Paris () is the capital and most populous city of France, with an estimated population of 2,165,423 residents in 2019 in an area of more than 105 km² (41 sq mi), making it the 30th most densely populated city in the world in 2020. Si ...

with the Continental Edison Company. Tesla began working in what was then a brand new industry, installing indoor incandescent lighting citywide in large scale electric power

utility As a topic of economics, utility is used to model worth or value. Its usage has evolved significantly over time. The term was introduced initially as a measure of pleasure or happiness as part of the theory of utilitarianism by moral philosophe ...

. The company had several subdivisions and Tesla worked at the Société Electrique Edison, the division in the

Ivry-sur-Seine Ivry-sur-Seine () is a commune in the Val-de-Marne department in the southeastern suburbs of Paris, France. It is located from the centre of Paris. Paris's main Asian district, the Quartier Asiatique in the 13th arrondissement, borders the ...

suburb of Paris in charge of installing the lighting system. There he gained a great deal of practical experience in electrical engineering. Management took notice of his advanced knowledge in engineering and physics and soon had him designing and building improved versions of generating

dynamo "Dynamo Electric Machine" (end view, partly section, ) A dynamo is an electrical generator that creates direct current using a commutator. Dynamos were the first electrical generators capable of delivering power for industry, and the foundati ...

s and motors. They also sent him on to troubleshoot engineering problems at other Edison utilities being built around France and in Germany.

Moving to the United States

Edison machine works goerck street new york 1881

In 1884, Edison manager Charles Batchelor, who had been overseeing the Paris installation, was brought back to the United States to manage the

, a manufacturing division situated in

New York City New York, often called New York City or NYC, is the List of United States cities by population, most populous city in the United States. With a 2020 population of 8,804,190 distributed over , New York City is also the L ...

, and asked that Tesla be brought to the United States as well. In June 1884, Tesla emigrated and began working almost immediately at the Machine Works on

Manhattan Manhattan (), known regionally as the City, is the most densely populated and geographically smallest of the five boroughs of New York City. The borough is also coextensive with New York County, one of the original counties of the U.S. state ...

Lower East Side The Lower East Side, sometimes abbreviated as LES, is a historic neighborhood in the southeastern part of Manhattan in New York City. It is located roughly between the Bowery and the East River from Canal to Houston streets. Traditionally an im ...

, an overcrowded shop with a workforce of several hundred machinists, laborers, managing staff, and 20 "field engineers" struggling with the task of building the large electric utility in that city. As in Paris, Tesla was working on troubleshooting installations and improving generators. Historian W. Bernard Carlson notes Tesla may have met company founder

Thomas Edison Thomas Alva Edison (February 11, 1847October 18, 1931) was an American inventor and businessman. He developed many devices in fields such as electric power generation, mass communication, sound recording, and motion pictures. These inventi ...

only a couple of times. One of those times was noted in Tesla's

autobiography An autobiography, sometimes informally called an autobio, is a self-written account of one's own life. It is a form of biography. Definition The word "autobiography" was first used deprecatingly by William Taylor in 1797 in the English peri ...

where, after staying up all night repairing the damaged dynamos on the ocean liner SS ''Oregon'', he ran into Batchelor and Edison, who made a quip about their "Parisian" being out all night. After Tesla told them he had been up all night fixing the ''Oregon'', Edison commented to Batchelor that "this is a damned good man". One of the projects given to Tesla was to develop an

arc lamp An arc lamp or arc light is a lamp that produces light by an electric arc (also called a voltaic arc). The carbon arc light, which consists of an arc between carbon electrodes in air, invented by Humphry Davy in the first decade of the 1800s, ...

-based street lighting system.Radmilo Ivanković' Dragan Petrović, review of the reprinted "Nikola Tesla: Notebook from the Edison Machine Works 1884–1885"
, teslauniverse.com Arc lighting was the most popular type of street lighting but it required high voltages and was incompatible with the Edison low-voltage incandescent system, causing the company to lose contracts in some cities. Tesla's designs were never put into production, possibly because of technical improvements in incandescent street lighting or because of an installation deal that Edison made with an arc lighting company. Tesla had been working at the Machine Works for a total of six months when he quit. What event precipitated his leaving is unclear. It may have been over a bonus he did not receive, either for redesigning generators or for the arc lighting system that was shelved. Tesla had previous run-ins with the Edison company over unpaid bonuses he believed he had earned. In his autobiography, Tesla stated the manager of the Edison Machine Works offered a $50,000 bonus to design "twenty-four different types of standard machines" "but it turned out to be a practical joke". Later versions of this story have Thomas Edison himself offering and then reneging on the deal, quipping "Tesla, you don't understand our American humor". The size of the bonus in either story has been noted as odd since Machine Works manager Batchelor was stingy with pay and the company did not have that amount of cash (equivalent to $1.4 million in 2021) on hand. Tesla's diary contains just one comment on what happened at the end of his employment, a note he scrawled across the two pages covering 7 December 1884, to 4 January 1885, saying "Good by to the Edison Machine Works".

Tesla Electric Light & Manufacturing

Soon after leaving the Edison company, Tesla was working on patenting an arc lighting system, possibly the same one he had developed at Edison. In March 1885, he met with patent attorney Lemuel W. Serrell, the same attorney used by Edison, to obtain help with submitting the patents. Serrell introduced Tesla to two businessmen, Robert Lane and Benjamin Vail, who agreed to finance an arc lighting manufacturing and utility company in Tesla's name, the Tesla Electric Light & Manufacturing. Tesla worked for the rest of the year obtaining the patents that included an improved DC generator, the first patents issued to Tesla in the US, and building and installing the system in

Rahway, New Jersey Rahway () is a city in southern Union County, in the U.S. state of New Jersey. A bedroom community of New York City, it is centrally located in the Rahway Valley region, in the New York metropolitan area. The city is southwest of Manhattan ...

. Tesla's new system gained notice in the technical press, which commented on its advanced features. The investors showed little interest in Tesla's ideas for new types of

motors and electrical transmission equipment. After the utility was up and running in 1886, they decided that the manufacturing side of the business was too competitive and opted to simply run an electric utility. They formed a new utility company, abandoning Tesla's company and leaving the inventor penniless. Tesla even lost control of the patents he had generated, since he had assigned them to the company in exchange for stock. He had to work at various electrical repair jobs and as a ditch digger for $2 per day. Later in life Tesla recounted that part of 1886 as a time of hardship, writing "My high education in various branches of science, mechanics and literature seemed to me like a mockery".

AC and the induction motor

In late 1886, Tesla met Alfred S. Brown, a

Western Union The Western Union Company is an American multinational financial services company, headquartered in Denver, Colorado. Founded in 1851 as the New York and Mississippi Valley Printing Telegraph Company in Rochester, New York, the company cha ...

superintendent, and New York attorney Charles Fletcher Peck. The two men were experienced in setting up companies and promoting inventions and patents for financial gain. Based on Tesla's new ideas for electrical equipment, including a thermo-magnetic motor idea, they agreed to back the inventor financially and handle his patents. Together they formed the Tesla Electric Company in April 1887, with an agreement that profits from generated patents would go to Tesla, to Peck and Brown, and to fund development. They set up a laboratory for Tesla at 89 Liberty Street in Manhattan, where he worked on improving and developing new types of electric motors, generators, and other devices. In 1887, Tesla developed an

that ran on

(AC), a power system format that was rapidly expanding in Europe and the United States because of its advantages in long-distance,

high-voltage High voltage electricity refers to electrical potential large enough to cause injury or damage. In certain industries, ''high voltage'' refers to voltage above a certain threshold. Equipment and Electrical conductor, conductors that carry high ...

transmission. The motor used polyphase current, which generated a

rotating magnetic field A rotating magnetic field is the resultant magnetic field produced by a system of coils symmetrically placed and supplied with polyphase currents. A rotating magnetic field can be produced by a poly-phase (two or more phases) current or by a singl ...

to turn the motor (a principle that Tesla claimed to have conceived in 1882). This innovative electric motor, patented in May 1888, was a simple self-starting design that did not need a

commutator In mathematics, the commutator gives an indication of the extent to which a certain binary operation fails to be commutative. There are different definitions used in group theory and ring theory. Group theory The commutator of two elements, ...

, thus avoiding sparking and the high maintenance of constantly servicing and replacing mechanical brushes. Along with getting the motor patented, Peck and Brown arranged to get the motor publicized, starting with independent testing to verify it was a functional improvement, followed by press releases sent to technical publications for articles to run concurrently with the issue of the patent. Physicist

William Arnold Anthony William Arnold Anthony (November 17, 1835 – May 29, 1908) was a U.S. physicist. Biography Anthony was born in Coventry, Rhode Island. He was educated at the Yale Scientific School (today Sheffield Scientific School) and graduated in 1860. Betwe ...

(who tested the motor) and ''Electrical World'' magazine editor Thomas Commerford Martin arranged for Tesla to demonstrate his AC motor on 16 May 1888 at the

American Institute of Electrical Engineers The American Institute of Electrical Engineers (AIEE) was a United States-based organization of electrical engineers that existed from 1884 through 1962. On January 1, 1963, it merged with the Institute of Radio Engineers (IRE) to form the Insti ...

. Engineers working for the

Westinghouse Electric & Manufacturing Company The Westinghouse Electric Corporation was an American manufacturing company founded in 1886 by George Westinghouse. It was originally named "Westinghouse Electric & Manufacturing Company" and was renamed "Westinghouse Electric Corporation" i ...

reported to

George Westinghouse George Westinghouse Jr. (October 6, 1846 – March 12, 1914) was an American entrepreneur and engineer based in Pennsylvania who created the railway air brake and was a pioneer of the electrical industry, receiving his first patent at the age ...

that Tesla had a viable AC motor and related power system—something Westinghouse needed for the alternating current system he was already marketing. Westinghouse looked into getting a patent on a similar commutator-less, rotating magnetic field-based induction motor developed in 1885 and presented in a paper in March 1888 by Italian physicist

Galileo Ferraris Galileo Ferraris (31 October 1847 – 7 February 1897) was an Italian university professor, physicist and electrical engineer, one of the pioneers of AC power system and inventor of the induction motor although he never patented his work. Many ...

, but decided that Tesla's patent would probably control the market. US390721

In July 1888, Brown and Peck negotiated a licensing deal with George Westinghouse for Tesla's polyphase induction motor and transformer designs for $60,000 in cash and stock and a royalty of $2.50 per AC horsepower produced by each motor. Westinghouse also hired Tesla for one year for the large fee of $2,000 ($ in today's dollars) per month to be a consultant at the Westinghouse Electric & Manufacturing Company's

Pittsburgh Pittsburgh ( ) is a city in the Commonwealth (U.S. state), Commonwealth of Pennsylvania, United States, and the county seat of Allegheny County, Pennsylvania, Allegheny County. It is the most populous city in both Allegheny County and Wester ...

labs. During that year, Tesla worked in Pittsburgh, helping to create an alternating current system to power the city's streetcars. He found it a frustrating period because of conflicts with the other Westinghouse engineers over how best to implement AC power. Between them, they settled on a 60-cycle AC system that Tesla proposed (to match the working frequency of Tesla's motor), but they soon found that it would not work for streetcars, since Tesla's induction motor could run only at a constant speed. They ended up using a DC

traction motor A traction motor is an electric motor used for propulsion of a vehicle, such as locomotives, electric or hydrogen vehicles, elevators or electric multiple unit. Traction motors are used in electrically powered rail vehicles ( electric multip ...

instead.

Market turmoil

Tesla's demonstration of his induction motor and Westinghouse's subsequent licensing of the patent, both in 1888, came at the time of extreme competition between electric companies. The three big firms, Westinghouse, Edison, and Thomson-Houston, were trying to grow in a capital-intensive business while financially undercutting each other. There was even a " war of currents" propaganda campaign going on with Edison Electric trying to claim their

direct current Direct current (DC) is one-directional flow of electric charge. An electrochemical cell is a prime example of DC power. Direct current may flow through a conductor such as a wire, but can also flow through semiconductors, insulators, or ev ...

system was better and safer than the Westinghouse alternating current system. Competing in this market meant Westinghouse would not have the cash or engineering resources to develop Tesla's motor and the related polyphase system right away. Two years after signing the Tesla contract, Westinghouse Electric was in trouble. The near collapse of

Barings Bank Barings Bank was a British merchant bank based in London, and one of England's oldest merchant banks after Berenberg Bank, Barings' close collaborator and German representative. It was founded in 1762 by Francis Baring, a British-born member ...

in London triggered the financial panic of 1890, causing investors to call in their loans to Westinghouse Electric. The sudden cash shortage forced the company to refinance its debts. The new lenders demanded that Westinghouse cut back on what looked like excessive spending on acquisition of other companies, research, and patents, including the per motor royalty in the Tesla contract. At that point, the Tesla induction motor had been unsuccessful and was stuck in development. Westinghouse was paying a $15,000-a-year guaranteed royalty even though operating examples of the motor were rare and polyphase power systems needed to run it was even rarer. In early 1891, George Westinghouse explained his financial difficulties to Tesla in stark terms, saying that, if he did not meet the demands of his lenders, he would no longer be in control of Westinghouse Electric and Tesla would have to "deal with the bankers" to try to collect future royalties. The advantages of having Westinghouse continue to champion the motor probably seemed obvious to Tesla and he agreed to release the company from the royalty payment clause in the contract. Six years later Westinghouse purchased Tesla's patent for a

lump sum A lump sum is a single payment of money, as opposed to a series of payments made over time (such as an annuity). The United States Department of Housing and Urban Development distinguishes between " price analysis" and "cost analysis" by whether ...

payment of $216,000 as part of a patent-sharing agreement signed with

General Electric General Electric Company (GE) is an American multinational conglomerate founded in 1892, and incorporated in New York state and headquartered in Boston. The company operated in sectors including healthcare, aviation, power, renewable ene ...

(a company created from the 1892 merger of Edison and Thomson-Houston).

New York laboratories

The money Tesla made from licensing his AC patents made him independently wealthy and gave him the time and funds to pursue his own interests. In 1889, Tesla moved out of the Liberty Street shop Peck and Brown had rented and for the next dozen years working out of a series of workshop/laboratory spaces in

. These included a lab at 175 Grand Street (1889–1892), the fourth floor of 33–35 South

Fifth Avenue Fifth Avenue is a major and prominent thoroughfare in the borough of Manhattan in New York City. It stretches north from Washington Square Park in Greenwich Village to West 143rd Street in Harlem. It is one of the most expensive shopping ...

(1892–1895), and sixth and seventh floors of 46 & 48 East

Houston Street Houston Street ( ) is a major east–west thoroughfare in Lower Manhattan in New York City. It runs the full width of the island of Manhattan, from FDR Drive along the East River in the east to the West Side Highway along the Hudson River i ...

(1895–1902). Tesla and his hired staff conducted some of his most significant work in these workshops.

Tesla coil

In the summer of 1889, Tesla traveled to the 1889 Exposition Universelle in Paris and learned of

Heinrich Hertz Heinrich Rudolf Hertz ( ; ; 22 February 1857 – 1 January 1894) was a German physicist who first conclusively proved the existence of the electromagnetic waves predicted by James Clerk Maxwell's equations of electromagnetism. The uni ...

's 1886–1888 experiments that proved the existence of

electromagnetic radiation In physics, electromagnetic radiation (EMR) consists of waves of the electromagnetic (EM) field, which propagate through space and carry momentum and electromagnetic radiant energy. It includes radio waves, microwaves, infrared, (visib ...

, including

radio wave Radio waves are a type of electromagnetic radiation with the longest wavelengths in the electromagnetic spectrum, typically with frequencies of 300 gigahertz ( GHz) and below. At 300 GHz, the corresponding wavelength is 1 mm (sho ...

s. Tesla found this new discovery "refreshing" and decided to explore it more fully. In repeating and then expanding on these experiments Tesla tried powering a

Ruhmkorff coil An induction coil or "spark coil" (archaically known as an inductorium or Ruhmkorff coil after Heinrich Rühmkorff) is a type of electrical transformer used to produce high-voltage pulses from a low-voltage direct current (DC) supply. p.98 T ...

with a high speed

alternator An alternator is an electrical generator that converts mechanical energy to electrical energy in the form of alternating current. For reasons of cost and simplicity, most alternators use a rotating magnetic field with a stationary armature.Gor ...

he had been developing as part of an improved arc lighting system but found that the high-frequency current overheated the iron core and melted the insulation between the primary and secondary windings in the coil. To fix this problem Tesla came up with his "oscillating transformer", with an air gap instead of insulating material between the primary and secondary windings and an iron core that could be moved to different positions in or out of the coil. Later called the Tesla coil, it would be used to produce high-

voltage Voltage, also known as electric pressure, electric tension, or (electric) potential difference, is the difference in electric potential between two points. In a static electric field, it corresponds to the work needed per unit of charge to ...

, low-

current Currents, Current or The Current may refer to: Science and technology * Current (fluid), the flow of a liquid or a gas ** Air current, a flow of air ** Ocean current, a current in the ocean *** Rip current, a kind of water current ** Current (stre ...

, high

frequency Frequency is the number of occurrences of a repeating event per unit of time. It is also occasionally referred to as ''temporal frequency'' for clarity, and is distinct from ''angular frequency''. Frequency is measured in hertz (Hz) which is eq ...

alternating-current Alternating current (AC) is an electric current which periodically reverses direction and changes its magnitude continuously with time in contrast to direct current (DC) which flows only in one direction. Alternating current is the form in which ...

electricity. He would use this resonant transformer circuit in his later wireless power work.

Citizenship

On 30 July 1891, aged 35, Tesla became a

naturalized citizen Naturalization (or naturalisation) is the legal act or process by which a non-citizen of a country may acquire citizenship or nationality of that country. It may be done automatically by a statute, i.e., without any effort on the part of the in ...

of the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country Continental United States, primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., ...

., Naturalization Index, NYC Courts, referenced in Carlson (2013), ''Tesla: Inventor of the Electrical Age'', p. H-41 In the same year, he patented his Tesla coil.

Wireless lighting

After 1890, Tesla experimented with transmitting power by inductive and capacitive coupling using high AC voltages generated with his Tesla coil., lecture delivered before the

, Columbia College, New York. Reprinted as a He attempted to develop a wireless lighting system based on near-field inductive and capacitive coupling and conducted a series of public demonstrations where he lit

Geissler tube A Geissler tube is an early gas discharge tube used to demonstrate the principles of electrical glow discharge, similar to modern neon lighting. The tube was invented by the German physicist and glassblower Heinrich Geissler in 1857. It cons ...

s and even incandescent light bulbs from across a stage. He spent most of the decade working on variations of this new form of lighting with the help of various investors but none of the ventures succeeded in making a commercial product out of his findings. In 1893 at St. Louis, Missouri, the

Franklin Institute The Franklin Institute is a science museum and the center of science education and research in Philadelphia, Pennsylvania. It is named after the American scientist and statesman Benjamin Franklin. It houses the Benjamin Franklin National Memori ...

Philadelphia Philadelphia, often called Philly, is the largest city in the Commonwealth of Pennsylvania, the sixth-largest city in the U.S., the second-largest city in both the Northeast megalopolis and Mid-Atlantic regions after New York City. Since ...

, Pennsylvania and the

National Electric Light Association The National Electric Light Association (NELA) was a national United States trade association that included the operators of electric central power generation stations, electrical supply companies, electrical engineers, scientists, educational i ...

, Tesla told onlookers that he was sure a system like his could eventually conduct "intelligible signals or perhaps even power to any distance without the use of wires" by conducting it through the Earth. Tesla served as a vice-president of the

from 1892 to 1894, the forerunner of the modern-day

IEEE The Institute of Electrical and Electronics Engineers (IEEE) is a 501(c)(3) professional association for electronic engineering and electrical engineering (and associated disciplines) with its corporate office in New York City and its operati ...

(along with the

Institute of Radio Engineers The Institute of Radio Engineers (IRE) was a professional organization which existed from 1912 until December 31, 1962. On January 1, 1963, it merged with the American Institute of Electrical Engineers (AIEE) to form the Institute of Electrical ...

Polyphase system and the Columbian Exposition

By the beginning of 1893, Westinghouse engineer Charles F. Scott and then

Benjamin G. Lamme Benjamin Garver Lamme (January 12, 1864 – July 8, 1924) was an American electrical engineer and chief engineer at Westinghouse, where he was responsible for the design of electrical power machines. Lamme created an efficient induction motor fr ...

had made progress on an efficient version of Tesla's induction motor. Lamme found a way to make the

polyphase system A polyphase system is a means of distributing alternating-current (AC) electrical power where the power transfer is constant during each electrical cycle. AC phase refers to the phase offset value (in degrees) between AC in multiple conducting ...

it would need compatible with older single-phase AC and DC systems by developing a

rotary converter A rotary converter is a type of electrical machine which acts as a mechanical rectifier, inverter or frequency converter. Rotary converters were used to convert alternating current (AC) to direct current (DC), or DC to AC power, before the adv ...

. Westinghouse Electric now had a way to provide electricity to all potential customers and started branding their polyphase AC system as the "Tesla Polyphase System". They believed that Tesla's patents gave them patent priority over other polyphase AC systems. Westinghouse Electric asked Tesla to participate in the 1893

World's Columbian Exposition The World's Columbian Exposition (also known as the Chicago World's Fair) was a world's fair held in Chicago in 1893 to celebrate the 400th anniversary of Christopher Columbus's arrival in the New World in 1492. The centerpiece of the Fair, hel ...

in Chicago where the company had a large space in the "Electricity Building" devoted to electrical exhibits. Westinghouse Electric won the bid to light the Exposition with alternating current and it was a key event in the history of AC power, as the company demonstrated to the American public the safety, reliability, and efficiency of an alternating current system that was polyphase and could also supply the other AC and DC exhibits at the fair. A special exhibit space was set up to display various forms and models of Tesla's induction motor. The rotating magnetic field that drove them was explained through a series of demonstrations including an ''

Egg of Columbus An egg of Columbus or Columbus' egg ( it, uovo di Colombo ) refers to a brilliant idea or discovery that seems simple or easy after the fact. The expression refers to an apocryphal story, dating from at least the 16th century, in which it is sai ...

'' that used the two-phase coil found in an induction motor to spin a copper egg making it stand on end. Tesla visited the fair for a week during its six-month run to attend the

International Electrical Congress The International Electrical Congress was a series of international meetings, from 1881 - 1904, in the then new field of applied electricity. The first meeting was initiated by the French government, including official national representatives, lea ...

and put on a series of demonstrations at the Westinghouse exhibit. A specially darkened room had been set up where Tesla showed his wireless lighting system, using a demonstration he had previously performed throughout America and Europe; these included using high-voltage, high-frequency alternating current to light wireless

gas-discharge lamp Gas-discharge lamps are a family of artificial light sources that generate light by sending an electric discharge through an ionized gas, a plasma. Typically, such lamps use a noble gas (argon, neon, krypton, and xenon) or a mixture of t ...

s. An observer noted:

Steam-powered oscillating generator

During his presentation at the International Electrical Congress in the Columbian Exposition Agriculture Hall, Tesla introduced his steam powered reciprocating electricity generator that he patented that year, something he thought was a better way to generate alternating current. Steam was forced into the oscillator and rushed out through a series of ports, pushing a piston up and down that was attached to an armature. The magnetic armature vibrated up and down at high speed, producing an alternating

magnetic field A magnetic field is a vector field that describes the magnetic influence on moving electric charges, electric currents, and magnetic materials. A moving charge in a magnetic field experiences a force perpendicular to its own velocity and to ...

. This induced alternating electric current in the wire coils located adjacent. It did away with the complicated parts of a steam engine/generator, but never caught on as a feasible engineering solution to generate electricity.

Consulting on Niagara

In 1893, Edward Dean Adams, who headed the

Niagara Falls Niagara Falls () is a group of three waterfalls at the southern end of Niagara Gorge, spanning the Canada–United States border, border between the Provinces and territories of Canada, province of Ontario in Canada and the U.S. state, state ...

Cataract Construction Company, sought Tesla's opinion on what system would be best to transmit power generated at the falls. Over several years, there had been a series of proposals and open competitions on how best to do it. Among the systems proposed by several US and European companies were two-phase and three-phase AC, high-voltage DC, and compressed air. Adams asked Tesla for information about the current state of all the competing systems. Tesla advised Adams that a two-phased system would be the most reliable and that there was a Westinghouse system to light incandescent bulbs using two-phase alternating current. The company awarded a contract to Westinghouse Electric for building a two-phase AC generating system at the Niagara Falls, based on Tesla's advice and Westinghouse's demonstration at the Columbian Exposition. At the same time, a further contract was awarded to General Electric to build the AC distribution system.

The Nikola Tesla Company

In 1895, Edward Dean Adams, impressed with what he saw when he toured Tesla's lab, agreed to help found the Nikola Tesla Company, set up to fund, develop, and market a variety of previous Tesla patents and inventions as well as new ones. Alfred Brown signed on, bringing along patents developed under Peck and Brown. The board was filled out with William Birch Rankine and Charles F. Coaney. It found few investors since the mid-1890s were a tough time financially, and the wireless lighting and oscillators patents it was set up to market never panned out. The company handled Tesla's patents for decades to come.

Lab fire

In the early morning hours of 13 March 1895, the South Fifth Avenue building that housed Tesla's lab caught fire. It started in the basement of the building and was so intense Tesla's 4th-floor lab burned and collapsed into the second floor. The fire not only set back Tesla's ongoing projects, but it also destroyed a collection of early notes and research material, models, and demonstration pieces, including many that had been exhibited at the 1893 Worlds Colombian Exposition. Tesla told ''

The New York Times ''The New York Times'' (''the Times'', ''NYT'', or the Gray Lady) is a daily newspaper based in New York City with a worldwide readership reported in 2020 to comprise a declining 840,000 paid print subscribers, and a growing 6 million paid ...

'' "I am in too much grief to talk. What can I say?". After the fire Tesla moved to 46 & 48 East Houston Street and rebuilt his lab on the 6th and 7th floors.

X-ray experimentation

Starting in 1894, Tesla began investigating what he referred to as

radiant energy Radiant may refer to: Computers, software, and video games * Radiant (software), a content management system * GtkRadiant, a level editor created by id Software for their games * Radiant AI, a technology developed by Bethesda Softworks for ''Th ...

of "invisible" kinds after he had noticed damaged film in his laboratory in previous experiments (later identified as "Roentgen rays" or "

X-rays An X-ray, or, much less commonly, X-radiation, is a penetrating form of high-energy electromagnetic radiation. Most X-rays have a wavelength ranging from 10 picometers to 10 nanometers, corresponding to frequencies in the range 30&nbs ...

"). His early experiments were with

Crookes tube A Crookes tube (also Crookes–Hittorf tube) is an early experimental electrical discharge tube, with partial vacuum, invented by English physicist William Crookes and others around 1869-1875, in which cathode rays, streams of electrons, were ...

s, a

cold cathode A cold cathode is a cathode that is not electrically heated by a filament.A negatively charged electrode emits electrons or is the positively charged terminal. For more, see field emission. A cathode may be considered "cold" if it emits more el ...

electrical discharge tube. Tesla may have inadvertently captured an X-ray image—predating, by a few weeks,

Wilhelm Röntgen Wilhelm Conrad Röntgen (; ; 27 March 184510 February 1923) was a German mechanical engineer and physicist, who, on 8 November 1895, produced and detected electromagnetic radiation in a wavelength range known as X-rays or Röntgen rays, an achie ...

's December 1895 announcement of the discovery of X-rays—when he tried to photograph Mark Twain illuminated by a

, an earlier type of gas discharge tube. The only thing captured in the image was the metal locking screw on the camera lens. In March 1896, after hearing of Röntgen's discovery of X-ray and X-ray imaging (

radiography Radiography is an imaging technique using X-rays, gamma rays, or similar ionizing radiation and non-ionizing radiation to view the internal form of an object. Applications of radiography include medical radiography ("diagnostic" and "therapeu ...

), Tesla proceeded to do his own experiments in X-ray imaging, developing a high-energy single-terminal

vacuum tube A vacuum tube, electron tube, valve (British usage), or tube (North America), is a device that controls electric current flow in a high vacuum between electrodes to which an electric potential difference has been applied. The type known as ...

of his own design that had no target electrode and that worked from the output of the Tesla coil (the modern term for the phenomenon produced by this device is ''

bremsstrahlung ''Bremsstrahlung'' (), from "to brake" and "radiation"; i.e., "braking radiation" or "deceleration radiation", is electromagnetic radiation produced by the deceleration of a charged particle when deflected by another charged particle, typical ...

'' or ''braking radiation''). In his 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". Tesla noted the hazards of working with his circuit and single-node X-ray-producing devices. In his many notes on 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 by the

ozone Ozone (), or trioxygen, is an inorganic molecule with the chemical formula . It is a pale blue gas with a distinctively pungent smell. It is an allotrope of oxygen that is much less stable than the diatomic allotrope , breaking down in the l ...

generated in contact with the skin, and to a lesser extent, by

nitrous acid Nitrous acid (molecular formula ) is a weak and monoprotic acid known only in solution, in the gas phase and in the form of nitrite () salts. Nitrous acid is used to make diazonium salts from amines. The resulting diazonium salts are reagent ...

. Tesla incorrectly believed that X-rays were longitudinal waves, such as those produced in waves in plasmas. These plasma waves can occur in force-free magnetic fields. On 11 July 1934, the ''

New York Herald Tribune The ''New York Herald Tribune'' was a newspaper published between 1924 and 1966. It was created in 1924 when Ogden Mills Reid of the ''New-York Tribune'' acquired the '' New York Herald''. It was regarded as a "writer's newspaper" and competed ...

'' published an article on Tesla, in which he recalled an event that occasionally took place while experimenting with his single-electrode vacuum tubes. A minute particle would break off the cathode, pass out of the tube, and physically strike him:

Tesla said he could feel a sharp stinging pain where it entered his body, and again at the place where it passed out. In comparing these particles with the bits of metal projected by his "electric gun", Tesla said, "The particles in the beam of force ... will travel much faster than such particles ... and they will travel in concentrations".

Radio remote control

In 1898, Tesla demonstrated a boat that used a

coherer The coherer was a primitive form of radio signal detector used in the first radio receivers during the wireless telegraphy era at the beginning of the 20th century. Its use in radio was based on the 1890 findings of French physicist Édouard Bran ...

-based

radio control Radio control (often abbreviated to RC) is the use of control signals transmitted by radio to remotely control a device. Examples of simple radio control systems are garage door openers and keyless entry systems for vehicles, in which a smal ...

—which he dubbed "telautomaton"—to the public during an electrical exhibition at

Madison Square Garden Madison Square Garden, colloquially known as The Garden or by its initials MSG, is a multi-purpose indoor arena in New York City. It is located in Midtown Manhattan between Seventh and Eighth avenues from 31st to 33rd Street, above Pennsylv ...

. Tesla tried to sell his idea to the US military as a type of radio-controlled

torpedo A modern torpedo is an underwater ranged weapon launched above or below the water surface, self-propelled towards a target, and with an explosive warhead designed to detonate either on contact with or in proximity to the target. Historically, ...

, but they showed little interest. Remote

remained a novelty until World War I and afterward, when a number of countries used it in military programs. Tesla took the opportunity to further demonstrate "Teleautomatics" in an address to a meeting of the Commercial Club in

Chicago (''City in a Garden''); I Will , image_map = , map_caption = Interactive Map of Chicago , coordinates = , coordinates_footnotes = , subdivision_type = List of sovereign states, Count ...

, while he was travelling to

, on 13 May 1899.

Wireless power

From the 1890s through 1906, Tesla spent a great deal of his time and fortune on a series of projects trying to develop the transmission of electrical power without wires. It was an expansion of his idea of using coils to transmit power that he had been demonstrating in wireless lighting. He saw this as not only a way to transmit large amounts of power around the world but also, as he had pointed out in his earlier lectures, a way to transmit worldwide communications. At the time Tesla was formulating his ideas, there was no feasible way to wirelessly transmit communication signals over long distances, let alone large amounts of power. Tesla had studied radio waves early on, and came to the conclusion that part of the existing study on them, by Hertz, was incorrect. Also, this new form of radiation was widely considered at the time to be a short-distance phenomenon that seemed to die out in less than a mile. Tesla noted that, even if theories on radio waves were true, they were totally worthless for his intended purposes since this form of "invisible light" would diminish over a distance just like any other radiation and would travel in straight lines right out into space, becoming "hopelessly lost". By the mid-1890s, Tesla was working on the idea that he might be able to conduct electricity long distance through the Earth or the atmosphere, and began working on experiments to test this idea including setting up a large resonance transformer magnifying transmitter in his East Houston Street lab.My Inventions: The Autobiography of Nikola Tesla, Hart Brothers, 1982, Ch. 5, Seeming to borrow from a common idea at the time that the Earth's atmosphere was conductive, he proposed a system composed of balloons suspending, transmitting, and receiving, electrodes in the air above in altitude, where he thought the lower pressure would allow him to send high voltages (millions of volts) long distances.

Colorado Springs

To further study the conductive nature of low-pressure air, Tesla set up an experimental station at high altitude in Colorado Springs during 1899.''Nikola Tesla On His Work With Alternating Currents and Their Application to Wireless Telegraphy, Telephony, and Transmission of Power'', Leland I. Anderson, 21st Century Books, 2002, p. 109, . There he could safely operate much larger coils than in the cramped confines of his New York lab, and an associate had made an arrangement for the

El Paso Power Company El Paso Electric is a Texas-based public utility company, engaging in the generation, transmission, and distribution of electricity in west Texas and southern New Mexico. Its energy sources consist of nuclear fuel, natural gas, purchased power, so ...

to supply alternating current free of charge. To fund his experiments, he convinced

John Jacob Astor IV John Jacob Astor IV (July 13, 1864 – April 15, 1912) was an American business magnate, real estate developer, investor, writer, lieutenant colonel in the Spanish–American War, and a prominent member of the Astor family. He died in the sink ...

to invest $100,000 ($ in today's dollars) to become a majority shareholder in the Nikola Tesla Company. Astor thought he was primarily investing in the new wireless lighting system. Instead, Tesla used the money to fund his Colorado Springs experiments. Upon his arrival, he told reporters that he planned to conduct

wireless telegraphy Wireless telegraphy or radiotelegraphy is transmission of text messages by radio waves, analogous to electrical telegraphy using cables. Before about 1910, the term ''wireless telegraphy'' was also used for other experimental technologies for ...

experiments, transmitting signals from

Pikes Peak Pikes Peak is the highest summit of the southern Front Range of the Rocky Mountains, in North America. The ultra-prominent fourteener is located in Pike National Forest, west of downtown Colorado Springs, Colorado. The town of Manitou S ...

to Paris. There, he conducted experiments with a large coil operating in the megavolts range, producing artificial lightning (and thunder) consisting of millions of volts and discharges of up to in length, and, at one point, inadvertently burned out the generator in El Paso, causing a power outage. The observations he made of the electronic noise of lightning strikes led him to (incorrectly) conclude that he could use the entire globe of the Earth to conduct electrical energy. During his time at his laboratory, Tesla observed unusual signals from his receiver which he speculated to be communications from another planet. He mentioned them in a letter to a reporter in December 1899 and to the

Red Cross Society The International Red Cross and Red Crescent Movement, the world's largest group of non-governmental organizations working on humanitarian aid, is composed of the following bodies: *The ''International Committee of the Red Cross'' (ICRC), a comm ...

in December 1900. Reporters treated it as a sensational story and jumped to the conclusion Tesla was hearing signals from

Mars Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System, only being larger than Mercury. In the English language, Mars is named for the Roman god of war. Mars is a terrestrial planet with a thin at ...

. He expanded on the signals he heard in a 9 February 1901 ''Collier's Weekly'' article entitled "Talking With Planets", where he said it had not been immediately apparent to him that he was hearing "intelligently controlled signals" and that the signals could have come from Mars,

Venus Venus is the second planet from the Sun. It is sometimes called Earth's "sister" or "twin" planet as it is almost as large and has a similar composition. As an interior planet to Earth, Venus (like Mercury) appears in Earth's sky never f ...

, or other planets. It has been hypothesized that he may have intercepted

Guglielmo Marconi Guglielmo Giovanni Maria Marconi, 1st Marquis of Marconi (; 25 April 187420 July 1937) was an Italian inventor and electrical engineer, known for his creation of a practical radio wave-based wireless telegraph system. This led to Marconi ...

's European experiments in July 1899—Marconi may have transmitted the letter S (dot/dot/dot) in a naval demonstration, the same three impulses that Tesla hinted at hearing in Colorado—or signals from another experimenter in wireless transmission. Tesla had an agreement with the editor of '' The Century Magazine'' to produce an article on his findings. The magazine sent a photographer to Colorado to photograph the work being done there. The article, titled "The Problem of Increasing Human Energy", appeared in the June 1900 edition of the magazine. He explained the superiority of the wireless system he envisioned but the article was more of a lengthy philosophical treatise than an understandable scientific description of his work, illustrated with what were to become iconic images of Tesla and his Colorado Springs experiments.

Wardenclyffe

Tesla made the rounds in New York trying to find investors for what he thought would be a viable system of wireless transmission, wining and dining them at the

Waldorf-Astoria The Waldorf Astoria New York is a luxury hotel and condominium residence in Midtown Manhattan in New York City. The structure, at 301 Park Avenue between 49th and 50th Streets, is a 47-story Art Deco landmark designed by architects Schult ...

's Palm Garden (the hotel where he was living at the time), The Players Club, and

Delmonico's Delmonico's is the name of a series of restaurants that operated in New York City, with the present version located at 56 Beaver Street in the Financial District of Manhattan. The original version was widely recognized as the United States ...

. In March 1901, he obtained $150,000 ($ in today's dollars) from

J. P. Morgan John Pierpont Morgan Sr. (April 17, 1837 – March 31, 1913) was an American financier and investment banker who dominated corporate finance on Wall Street throughout the Gilded Age. As the head of the banking firm that ultimately became known ...

in return for a 51% share of any generated wireless patents, and began planning the

facility to be built in Shoreham, New York, east of the city on the North Shore of Long Island. By July 1901, Tesla had expanded his plans to build a more powerful transmitter to leap ahead of Marconi's radio-based system, which Tesla thought was a copy of his own. He approached Morgan to ask for more money to build the larger system, but Morgan refused to supply any further funds. In December 1901, Marconi successfully transmitted the letter S from England to

Newfoundland Newfoundland and Labrador (; french: Terre-Neuve-et-Labrador; frequently abbreviated as NL) is the easternmost province of Canada, in the country's Atlantic region. The province comprises the island of Newfoundland and the continental region ...

, defeating Tesla in the race to be first to complete such a transmission. A month after Marconi's success, Tesla tried to get Morgan to back an even larger plan to transmit messages and power by controlling "vibrations throughout the globe". Over the next five years, Tesla wrote more than 50 letters to Morgan, pleading for and demanding additional funding to complete the construction of Wardenclyffe. Tesla continued the project for another nine months into 1902. The tower was erected to its full height of . In June 1902, Tesla moved his lab operations from Houston Street to Wardenclyffe. Investors on

Wall Street Wall Street is an eight-block-long street in the Financial District of Lower Manhattan in New York City. It runs between Broadway in the west to South Street and the East River in the east. The term "Wall Street" has become a metonym for ...

were putting their money into Marconi's system, and some in the press began turning against Tesla's project, claiming it was a hoax. The project came to a halt in 1905, and in 1906, the financial problems and other events may have led to what Tesla biographer Marc J. Seifer suspects was a nervous breakdown on Tesla's part. Tesla mortgaged the Wardenclyffe property to cover his debts at the Waldorf-Astoria, which eventually amounted to $20,000 ($ in today's dollars). He lost the property in foreclosure in 1915, and in 1917 the Tower was demolished by the new owner to make the land a more viable real estate asset.

Later years

After Wardenclyffe closed, Tesla continued to write to Morgan; after "the great man" died, Tesla wrote to Morgan's son Jack, trying to get further funding for the project. In 1906, Tesla opened offices at 165 Broadway in Manhattan, trying to raise further funds by developing and marketing his patents. He went on to have offices at the Metropolitan Life Tower from 1910 to 1914; rented for a few months at the

Woolworth Building The Woolworth Building is an early American skyscraper designed by architect Cass Gilbert located at 233 Broadway in the Tribeca neighborhood of Manhattan in New York City. It was the tallest building in the world from 1913 to 1930, with a ...

, moving out because he could not afford the rent; and then to office space at 8 West 40th Street from 1915 to 1925. After moving to 8 West 40th Street, he was effectively bankrupt. Most of his patents had run out and he was having trouble with the new inventions he was trying to develop.

Bladeless turbine

On his 50th birthday, in 1906, Tesla demonstrated a 16,000 rpm bladeless turbine. During 1910–1911, at the Waterside Power Station in New York, several of his bladeless turbine engines were tested at 100–5,000 hp. Tesla worked with several companies including from 1919 to 1922 in

Milwaukee Milwaukee ( ), officially the City of Milwaukee, is both the most populous and most densely populated city in the U.S. state of Wisconsin and the county seat of Milwaukee County. With a population of 577,222 at the 2020 census, Milwaukee i ...

, for

Allis-Chalmers Allis-Chalmers was a U.S. manufacturer of machinery for various industries. Its business lines included agricultural equipment, construction equipment, power generation and power transmission equipment, and machinery for use in industrial s ...

. He spent most of his time trying to perfect the Tesla turbine with Hans Dahlstrand, the head engineer at the company, but engineering difficulties meant it was never made into a practical device. Tesla did license the idea to a precision instrument company and it found use in the form of luxury car

speedometer A speedometer or speed meter is a gauge that measures and displays the instantaneous speed of a vehicle. Now universally fitted to motor vehicles, they started to be available as options in the early 20th century, and as standard equipment f ...

s and other instruments.

Wireless lawsuits

When

World War I World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was List of wars and anthropogenic disasters by death toll, one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, ...

broke out, the British cut the transatlantic telegraph cable linking the US to

Germany Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, and the most populous member state of the European Union. Germany is situated betwee ...

in order to control the flow of information between the two countries. They also tried to shut off German wireless communication to and from the US by having the US Marconi Company sue the German radio company

Telefunken Telefunken was a German radio and television apparatus company, founded in Berlin in 1903, as a joint venture of Siemens & Halske and the ''Allgemeine Elektrizitäts-Gesellschaft'' (AEG) ('General electricity company'). The name "Telefunken" ap ...

for patent infringement. Telefunken brought in the physicists Jonathan Zenneck and

Karl Ferdinand Braun Karl Ferdinand Braun (; 6 June 1850 – 20 April 1918) was a German electrical engineer, inventor, physicist and Nobel laureate in physics. Braun contributed significantly to the development of radio and television technology: he shared the ...

for their defense, and hired Tesla as a witness for two years for $1,000 a month. The case stalled and then went moot when the US entered the war against Germany in 1917. In 1915, Tesla attempted to sue the

Marconi Company The Marconi Company was a British telecommunications and engineering company that did business under that name from 1963 to 1987. Its roots were in the Wireless Telegraph & Signal Company founded by Italian inventor Guglielmo Marconi in 189 ...

for infringement of his wireless tuning patents. Marconi's initial radio patent had been awarded in the US in 1897, but his 1900 patent submission covering improvements to radio transmission had been rejected several times, before it was finally approved in 1904, on the grounds that it infringed on other existing patents including two 1897 Tesla wireless power tuning patents. Tesla's 1915 case went nowhere, but in a related case, where the Marconi Company tried to sue the US government over WWI patent infringements, a

Supreme Court of the United States The Supreme Court of the United States (SCOTUS) is the highest court in the federal judiciary of the United States. It has ultimate appellate jurisdiction over all U.S. Federal tribunals in the United States, federal court cases, and over Stat ...

1943 decision restored the prior patents of

Oliver Lodge Sir Oliver Joseph Lodge, (12 June 1851 – 22 August 1940) was a British physicist and writer involved in the development of, and holder of key patents for, radio. He identified electromagnetic radiation independent of Hertz's proof and at his ...

, John Stone, and Tesla. The court declared that their decision had no bearing on Marconi's claim as the first to achieve radio transmission, just that since Marconi's claim to certain patented improvements were questionable, the company could not claim infringement on those same patents.

Nobel Prize rumors

On 6 November 1915, a

Reuters Reuters ( ) is a news agency owned by Thomson Reuters Corporation. It employs around 2,500 journalists and 600 photojournalists in about 200 locations worldwide. Reuters is one of the largest news agencies in the world. The agency was est ...

news agency report from London had the 1915

Nobel Prize in Physics ) , image = Nobel Prize.png , alt = A golden medallion with an embossed image of a bearded man facing left in profile. To the left of the man is the text "ALFR•" then "NOBEL", and on the right, the text (smaller) "NAT•" then " ...

awarded to Thomas Edison and Nikola Tesla; however, on 15 November, a Reuters story from Stockholm stated the prize that year was being awarded to

William Henry Bragg Sir William Henry Bragg (2 July 1862 – 12 March 1942) was an English physicist, chemist, mathematician, and active sportsman who uniquelyThis is still a unique accomplishment, because no other parent-child combination has yet shared a Nob ...

and

Lawrence Bragg Sir William Lawrence Bragg, (31 March 1890 – 1 July 1971) was an Australian-born British physicist and X-ray crystallographer, discoverer (1912) of Bragg's law of X-ray diffraction, which is basic for the determination of crystal struct ...

"for their services in the analysis of crystal structure by means of X-rays". There were unsubstantiated rumors at the time that either Tesla or Edison had refused the prize. The Nobel Foundation said, "Any rumor that a person has not been given a Nobel Prize because he has made known his intention to refuse the reward is ridiculous"; a recipient could decline a Nobel Prize only after he is announced a winner. There have been subsequent claims by Tesla biographers that Edison and Tesla were the original recipients and that neither was given the award because of their animosity toward each other; that each sought to minimize the other's achievements and right to win the award; that both refused ever to accept the award if the other received it first; that both rejected any possibility of sharing it; and even that a wealthy Edison refused it to keep Tesla from getting the $20,000 prize money. In the years after these rumors, neither Tesla nor Edison won a Nobel prize (although Edison received one of 38 possible bids in 1915 and Tesla received one of 38 possible bids in 1937).

Other awards, patents and ideas

Tesla won numerous medals and awards over this time. They include: * Grand Officer of the

Order of St. Sava The Royal Order of St. Sava is an Order of merit, first awarded by the Kingdom of Serbia in 1883 and later by the Kingdom of Serbs, Croats and Slovenes, and the Kingdom of Yugoslavia. It was awarded to nationals and foreigners for meritorious ach ...

(

Serbia Serbia (, ; Serbian: , , ), officially the Republic of Serbia ( Serbian: , , ), is a landlocked country in Southeastern and Central Europe, situated at the crossroads of the Pannonian Basin and the Balkans. It shares land borders with Hu ...

, 1892) *

Elliott Cresson Medal The Elliott Cresson Medal, also known as the Elliott Cresson Gold Medal, was the highest award given by the Franklin Institute. The award was established by Elliott Cresson, life member of the Franklin Institute, with $1,000 granted in 1848. The ...

(

, USA, 1894) * Grand Cross of the

Order of Prince Danilo I The Order of Prince Danilo I ( cnr, Орден Књаза Данила I, translit=Orden Knjaza Danila I) was an order of the Principality and later Kingdom, of Montenegro. It is currently a dynastic order granted by the head of the House of Pet ...

(

Montenegro ) , image_map = Europe-Montenegro.svg , map_caption = , image_map2 = , capital = Podgorica , coordinates = , largest_city = capital , official_languages = ...

, 1895) * AIEE Edison Medal (

Institute of Electrical and Electronics Engineers The Institute of Electrical and Electronics Engineers (IEEE) is a 501(c)(3) professional association for electronic engineering and electrical engineering (and associated disciplines) with its corporate office in New York City and its operation ...

, USA, 1916) * Grand Cross of the

(

Yugoslavia Yugoslavia (; sh-Latn-Cyrl, separator=" / ", Jugoslavija, Југославија ; sl, Jugoslavija ; mk, Југославија ;; rup, Iugoslavia; hu, Jugoszlávia; rue, label= Pannonian Rusyn, Югославия, translit=Juhoslavij ...

, 1926) * Cross of the Order of the Yugoslav Crown (

, 1931) *

John Scott Medal John Scott Award, created in 1816 as the John Scott Legacy Medal and Premium, is presented to men and women whose inventions improved the "comfort, welfare, and happiness of human kind" in a significant way. "...the John Scott Medal Fund, establish ...

(

Philadelphia City Council The Philadelphia City Council, the legislative body of Philadelphia, Pennsylvania, consists of ten members elected by district and seven members elected at-large. The council president is elected by the members from among their number. Each ...

, USA, 1934) * Order of the White Eagle (

, 1936) * Grand Cross of the

Order of the White Lion The Order of the White Lion ( cs, Řád Bílého lva) is the highest order of the Czech Republic. It continues a Czechoslovak order of the same name created in 1922 as an award for foreigners (Czechoslovakia had no civilian decoration for its ...

(

Czechoslovakia , rue, Чеськословеньско, , yi, טשעכאסלאוואקיי, , common_name = Czechoslovakia , life_span = 1918–19391945–1992 , p1 = Austria-Hungary , image_p1 ...

, 1937) * Medal of the

University of Paris , image_name = Coat of arms of the University of Paris.svg , image_size = 150px , caption = Coat of Arms , latin_name = Universitas magistrorum et scholarium Parisiensis , motto = ''Hic et ubique terrarum'' (Latin) , mottoeng = Here and a ...

(

Paris, France Paris () is the capital and most populous city of France, with an estimated population of 2,165,423 residents in 2019 in an area of more than 105 km² (41 sq mi), making it the 30th most densely populated city in the world in 2020. Si ...

, 1937) * The Medal of the University St. Clement of Ochrida (

Sofia, Bulgaria Sofia ( ; bg, София, Sofiya, ) is the capital and largest city of Bulgaria. It is situated in the Sofia Valley at the foot of the Vitosha mountain in the western parts of the country. The city is built west of the Iskar river, and h ...

, 1939)

Second banquet meeting of the Institute of Radio Engineers

Tesla attempted to market several devices based on the production of

. These included his 1900 Tesla Ozone Company selling an 1896 patented device based on his Tesla Coil, used to bubble ozone through different types of oils to make a therapeutic gel. He also tried to develop a variation of this a few years later as a room sanitizer for hospitals. Tesla theorized that the application of electricity to the brain enhanced intelligence. In 1912, he crafted "a plan to make dull students bright by saturating them unconsciously with electricity," wiring the walls of a schoolroom and, "saturating

he schoolroom He or HE may refer to: Language * He (pronoun), an English pronoun * He (kana), the romanization of the Japanese kana へ * He (letter), the fifth letter of many Semitic alphabets * He (Cyrillic), a letter of the Cyrillic script called ''He'' in ...

with infinitesimal electric waves vibrating at high frequency. The whole room will thus, Mr. Tesla claims, be converted into a health-giving and stimulating electromagnetic field or 'bath.'" The plan was, at least provisionally, approved by then superintendent of New York City schools, William H. Maxwell. Before

, Tesla sought overseas investors. After the war started, Tesla lost the funding he was receiving from his patents in European countries. In the August 1917 edition of the magazine ''

Electrical Experimenter ''The Electrical Experimenter'' was an American technical science magazine that was published monthly. It was established in May 1913, as the successor to '' Modern Electrics'', a combination of a magazine and mail-order catalog that had been pu ...

'', Tesla postulated that electricity could be used to locate submarines via using the reflection of an "electric ray" of "tremendous frequency," with the signal being viewed on a fluorescent screen (a system that has been noted to have a superficial resemblance to modern

radar Radar is a detection system that uses radio waves to determine the distance (''ranging''), angle, and radial velocity of objects relative to the site. It can be used to detect aircraft, Marine radar, ships, spacecraft, guided missiles, motor v ...

). Tesla was incorrect in his assumption that high-frequency radio waves would penetrate water.

Émile Girardeau Émile Girardeau (12 October 1882 – 7 December 1970) was a French engineer, famous for being the first person to patent the original system of frequencies that is used and known today as radar. He was born in 1882 at Luçon, France (the Vendée ...

, who helped develop France's first radar system in the 1930s, noted in 1953 that Tesla's general speculation that a very strong high-frequency signal would be needed was correct. Girardeau said, "(Tesla) was prophesying or dreaming, since he had at his disposal no means of carrying them out, but one must add that if he was dreaming, at least he was dreaming correctly". In 1928, Tesla received patent, , for a

biplane A biplane is a fixed-wing aircraft with two main wings stacked one above the other. The first powered, controlled aeroplane to fly, the Wright Flyer, used a biplane wing arrangement, as did many aircraft in the early years of aviation. While a ...

design capable of vertical take-off and landing (VTOL), which "gradually tilted through manipulation of the elevator devices" in flight until it was flying like a conventional plane. This impractical design was something Tesla thought thought would sell for less than $1,000. Tesla had a further office at 350 Madison Ave but by 1928 he no longer had a laboratory or funding.

Living circumstances

Tesla lived at the

Waldorf Astoria The Waldorf Astoria New York is a luxury hotel and condominium residence in Midtown Manhattan in New York City. The structure, at 301 Park Avenue between 49th and 50th Streets, is a 47-story Art Deco landmark designed by architects Schultze ...

from 1900 and ran up a large bill. He moved to the

St. Regis Hotel St. Regis Hotels & Resorts is a luxury hotel chain owned and managed by Marriott International. History In 1904, John Jacob Astor built the St. Regis New York as a sister property to his part-owned Waldorf-Astoria Hotel. Exhibiting luxury and ...

in 1922 and followed a pattern from then on of moving to a different hotel every few years and leaving unpaid bills behind.O'Neill (1944), p. 359 Tesla walked to the park every day to feed the

pigeons Columbidae () is a bird family consisting of doves and pigeons. It is the only family in the order Columbiformes. These are stout-bodied birds with short necks and short slender bills that in some species feature fleshy ceres. They primarily ...

. He began feeding them at the window of his hotel room and nursed injured birds back to health. He said that he had been visited by a certain injured white pigeon daily. He spent over $2,000 to care for the bird, including a device he built to support her comfortably while her broken wing and leg healed. Tesla stated: Tesla's unpaid bills, as well as complaints about the mess made by pigeons, led to his eviction from St. Regis in 1923. He was also forced to leave the Hotel Pennsylvania in 1930 and the Hotel Governor Clinton in 1934. At one point he also took rooms at the

Hotel Marguery Hotel Marguery was the first of three buildings located at 270 Park Avenue in the Midtown Manhattan neighborhood of New York City. It was a six-building apartment hotel complex built in 1917 as part of Terminal City. It was demolished in 195 ...

. Tesla moved to the Hotel New Yorker in 1934. At this time Westinghouse Electric & Manufacturing Company began paying him $125 per month in addition to paying his rent. Accounts of how this came about vary. Several sources claim that Westinghouse was concerned, or possibly warned, about potential bad publicity arising from the impoverished conditions in which their former star inventor was living. The payment has been described as being couched as a "consulting fee" to get around Tesla's aversion to accepting charity. Tesla biographer Marc Seifer described the Westinghouse payments as a type of "unspecified settlement". In any case, Westinghouse provided the funds for Tesla for the rest of his life.

Birthday press conferences

In 1931, a young journalist whom Tesla befriended, Kenneth M. Swezey, organized a celebration for the inventor's 75th birthday. Tesla received congratulations from figures in science and engineering such as

Albert Einstein Albert Einstein ( ; ; 14 March 1879 – 18 April 1955) was a German-born theoretical physicist, widely acknowledged to be one of the greatest and most influential physicists of all time. Einstein is best known for developing the theor ...

, and he was also featured on the cover of ''Time'' magazine. The cover caption "All the world's his power house" noted his contribution to

electrical power generation Electricity generation is the process of generating electric power from sources of primary energy. For utilities in the electric power industry, it is the stage prior to its delivery ( transmission, distribution, etc.) to end users or its st ...

. The party went so well that Tesla made it an annual event, an occasion where he would put out a large spread of food and drink—featuring dishes of his own creation. He invited the press in order to see his inventions and hear stories about his past exploits, views on current events, and sometimes baffling claims. Teslathoughtcamera

At the 1932 party, Tesla claimed he had invented a motor that would run on

cosmic ray Cosmic rays are high-energy particles or clusters of particles (primarily represented by protons or atomic nuclei) that move through space at nearly the speed of light. They originate from the Sun, from outside of the Solar System in our own ...

s. In 1933 at age 77, Tesla told reporters at the event that, after 35 years of work, he was on the verge of producing proof of a new form of energy. He claimed it was a theory of energy that was "violently opposed" to Einsteinian physics and could be tapped with an apparatus that would be cheap to run and last 500 years. He also told reporters he was working on a way to transmit individualized private radio wavelengths, working on breakthroughs in metallurgy, and developing a way to photograph the retina to record thought. At the 1934 occasion, Tesla told reporters he had designed a superweapon he claimed would end all war. He called it "

teleforce Teleforce is a proposed defensive weapon by Nikola Tesla that accelerated pellets or slugs of material to a high velocity inside a vacuum chamber via electrostatic repulsion and then fired them out of aimed nozzles at intended targets. Tesla cl ...

", but was usually referred to as his death ray. Tesla described it as a defensive weapon that would be put up along the border of a country and be used against attacking ground-based infantry or aircraft. Tesla never revealed detailed plans of how the weapon worked during his lifetime but, in 1984, they surfaced at the

Nikola Tesla Museum The Nikola Tesla Museum ( sr-cyr, Музеј Николе Тесле, Muzej Nikole Tesle) is a science museum located in the central area of Belgrade, Serbia. It is dedicated to honoring and displaying the life and work of Nikola Tesla as well as ...

archive in

Belgrade Belgrade ( , ;, ; names in other languages) is the capital and largest city in Serbia. It is located at the confluence of the Sava and Danube rivers and the crossroads of the Pannonian Plain and the Balkan Peninsula. Nearly 1,166,763 mi ...

. The treatise, ''The New Art of Projecting Concentrated Non-dispersive Energy through the Natural Media'', described an open-ended vacuum tube with a gas jet seal that allows particles to exit, a method of charging slugs of tungsten or mercury to millions of volts, and directing them in streams (through

electrostatic Electrostatics is a branch of physics that studies electric charges at rest ( static electricity). Since classical times, it has been known that some materials, such as amber, attract lightweight particles after rubbing. The Greek word for ...

repulsion). Tesla tried to attract interest of the

US War Department The United States Department of War, also called the War Department (and occasionally War Office in the early years), was the United States Cabinet department originally responsible for the operation and maintenance of the United States Army, a ...

, United Kingdom, Soviet Union, and Yugoslavia in the device. In 1935 at his 79th birthday party, Tesla covered many topics. He claimed to have discovered the cosmic ray in 1896 and invented a way to produce direct current by induction, and made many claims about his mechanical oscillator.Earl Sparling, NIKOLA TESLA, AT 79, USES EARTH TO TRANSMIT SIGNALS: EXPECTS TO HAVE $100,000,000 WITHIN TWO YEARS, New York World-Telegram, 11 July 1935 Describing the device (which he expected would earn him $100 million within two years) he told reporters that a version of his oscillator had caused an earthquake in his 46 East Houston Street lab and neighboring streets in

Lower Manhattan Lower Manhattan (also known as Downtown Manhattan or Downtown New York) is the southernmost part of Manhattan, the central borough for business, culture, and government in New York City, which is the most populated city in the United States with ...

in 1898. He went on to tell reporters his oscillator could destroy the

Empire State Building The Empire State Building is a 102-story Art Deco skyscraper in Midtown Manhattan, New York City. The building was designed by Shreve, Lamb & Harmon and built from 1930 to 1931. Its name is derived from " Empire State", the nickname of the ...

with 5 lbs of air pressure. He also explained a new technique he developed using his oscillators he called " Telegeodynamics", using it to transmit vibrations into the ground that he claimed would work over any distance to be used for communication or locating underground mineral deposits. In his 1937 Grand Ballroom of Hotel New Yorker event, Tesla received the

from the Czechoslovak ambassador and a medal from the Yugoslav ambassador. On questions concerning the death ray, Tesla stated, "But it is not an experiment ... I have built, demonstrated and used it. Only a little time will pass before I can give it to the world."

Death

In the fall of 1937 at the age of 81, after midnight one night, Tesla left the Hotel New Yorker to make his regular commute to the cathedral and library to feed the pigeons. While crossing a street a couple of blocks from the hotel, Tesla was unable to dodge a moving taxicab and was thrown to the ground. His back was severely wrenched and three of his ribs were broken in the accident. The full extent of his injuries was never known; Tesla refused to consult a doctor, an almost lifelong custom, and never fully recovered. On 7 January 1943, at the age of 86, Tesla died alone in Room 3327 of the Hotel New Yorker. His body was found by maid Alice Monaghan when she entered Tesla's room, ignoring the "do not disturb" sign that Tesla had placed on his door two days earlier. Assistant medical examiner H.W. Wembley examined the body and ruled that the cause of death had been

coronary thrombosis Coronary thrombosis is defined as the formation of a blood clot inside a blood vessel of the heart. This blood clot may then restrict blood flow within the heart, leading to heart tissue damage, or a myocardial infarction, also known as a heart at ...

(a type of

heart attack A myocardial infarction (MI), commonly known as a heart attack, occurs when blood flow decreases or stops to the coronary artery of the heart, causing damage to the heart muscle. The most common symptom is chest pain or discomfort which ma ...

). Two days later the

Federal Bureau of Investigation The Federal Bureau of Investigation (FBI) is the domestic intelligence and security service of the United States and its principal federal law enforcement agency. Operating under the jurisdiction of the United States Department of Justice ...

ordered the

Alien Property Custodian The Office of Alien Property Custodian was an office within the government of the United States during World War I and again during World War II, serving as a custodian to property that belonged to US enemies. The office was created in 1917 b ...

to seize Tesla's belongings. John G. Trump, a professor at M.I.T. and a well-known electrical engineer serving as a technical aide to the

National Defense Research Committee The National Defense Research Committee (NDRC) was an organization created "to coordinate, supervise, and conduct scientific research on the problems underlying the development, production, and use of mechanisms and devices of warfare" in the Un ...

, was called in to analyze the Tesla items. After a three-day investigation, Trump's report concluded that there was nothing which would constitute a hazard in unfriendly hands, stating: In a box purported to contain a part of Tesla's "death ray", Trump found a 45-year-old multidecade resistance box. Urn with Teslas ashes

On 10 January 1943, New York City mayor

Fiorello La Guardia Fiorello Henry LaGuardia (; born Fiorello Enrico LaGuardia, ; December 11, 1882September 20, 1947) was an American attorney and politician who represented New York in the House of Representatives and served as the 99th Mayor of New York City fr ...

read a eulogy written by Slovene-American author

Louis Adamic Louis Adamic ( sl, Alojzij Adamič; March 23, 1898 – September 4, 1951) was a Slovene-American author and translator, mostly known for writing about and advocating for ethnic diversity of the United States. Background Louis Adamic ...

live over the

WNYC WNYC is the trademark and a set of call letters shared by WNYC (AM) and WNYC-FM, a pair of nonprofit, noncommercial, public radio stations located in New York City. WNYC is owned by New York Public Radio (NYPR), a nonprofit organization that ...

radio while violin pieces "

Ave Maria The Hail Mary ( la, Ave Maria) is a traditional Christian prayer addressing Mary, the mother of Jesus. The prayer is based on two biblical passages featured in the Gospel of Luke: the Angel Gabriel's visit to Mary (the Annunciation) and Mary's ...

" and " Tamo daleko" were played in the background. On 12 January, two thousand people attended a state funeral for Tesla at the

Cathedral of St. John the Divine The Cathedral of St. John the Divine (sometimes referred to as St. John's and also nicknamed St. John the Unfinished) is the cathedral of the Episcopal Diocese of New York. It is at 1047 Amsterdam Avenue in the Morningside Heights neighborhood ...

in Manhattan. After the funeral, Tesla's body was taken to the

Ferncliff Cemetery Ferncliff Cemetery and Mausoleum is located at 280 Secor Road in the hamlet of Hartsdale, town of Greenburgh, Westchester County, New York, United States, about north of Midtown Manhattan. It was founded in 1902, and is non-sectarian. Fernc ...

in Ardsley, New York, where it was later cremated. The following day, a second service was conducted by prominent priests in the Trinity Chapel (today's Serbian Orthodox Cathedral of Saint Sava) in New York City.

Estate

In 1952, following pressure from Tesla's nephew, Sava Kosanović, Tesla's entire estate was shipped to Belgrade in 80 trunks marked N.T. In 1957, Kosanović's secretary Charlotte Muzar transported Tesla's ashes from the United States to Belgrade. The ashes are displayed in a gold-plated sphere on a marble pedestal in the

Patents

Tesla obtained around 300 patents worldwide for his inventions. Some of Tesla's patents are not accounted for, and various sources have discovered some that have lain hidden in patent archives. There are a minimum of 278 known patents issued to Tesla in 26 countries. Many of Tesla's patents were in the United States,

Britain Britain most often refers to: * The United Kingdom, a sovereign state in Europe comprising the island of Great Britain, the north-eastern part of the island of Ireland and many smaller islands * Great Britain, the largest island in the United King ...

, and

Canada Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by to ...

, but many other patents were approved in countries around the globe. Many inventions developed by Tesla were not put into patent protection.

Personal life and character

Appearance

Tesla was tall and weighed , with almost no weight variance from 1888 to about 1926. His appearance was described by newspaper editor Arthur Brisbane as "almost the tallest, almost the thinnest and certainly the most serious man who goes to Delmonico's regularly". He was an elegant, stylish figure in New York City, meticulous in his grooming, clothing, and regimented in his daily activities, an appearance he maintained so as to further his business relationships. He was also described as having light eyes, "very big hands", and "remarkably big" thumbs.

Eidetic memory

Tesla read many works, memorizing complete books, and supposedly possessed a photographic memory. He was a

polyglot Multilingualism is the use of more than one language, either by an individual speaker or by a group of speakers. It is believed that multilingual speakers outnumber monolingual speakers in the world's population. More than half of all Eu ...

, speaking eight languages:

Serbo-Croatian Serbo-Croatian () – also called Serbo-Croat (), Serbo-Croat-Bosnian (SCB), Bosnian-Croatian-Serbian (BCS), and Bosnian-Croatian-Montenegrin-Serbian (BCMS) – is a South Slavic language and the primary language of Serbia, Croatia, Bosnia an ...

, Czech, English, French, German, Hungarian, Italian, and

Latin Latin (, or , ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through ...

. Tesla related in his autobiography that he experienced detailed moments of inspiration. During his early life, Tesla was repeatedly stricken with illness. Blinding flashes of light would appear before his eyes, often accompanied by visions. Often, the visions were linked to a word or idea he might have come across; at other times they provided the solution to a particular problem he had encountered. Just by hearing the name of an item, he could envision it in realistic detail. Tesla visualized 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 but worked from memory. Beginning in his childhood, Tesla had frequent flashbacks to events that had happened previously in his life. He noted in his

that this affliction had developed his powers of observation and enabled him to discover a "truth of great importance", namely that every thought he conceived was suggested by an external impression. Tesla further wrote that "deficient observation was merely a form of ignorance and responsible for the many morbid notions and foolish ideas prevailing."

Relationships

Tesla was a lifelong bachelor, who had once explained that his chastity was very helpful to his scientific abilities. He once said in earlier years that he felt he could never be worthy enough for a woman, considering women superior in every way. His opinion had started to sway in later years when he felt that women were trying to outdo men and make themselves more dominant. This "new woman" was met with much indignation from Tesla, who felt that women were losing their femininity by trying to be in power. In an interview with the ''Galveston Daily News'' on 10 August 1924 he stated, "In place of the soft-voiced, a gentlewoman of my reverent worship, has come the woman who thinks that her chief success in life lies in making herself as much as possible like man—in dress, voice and actions, in sports and achievements of every kind ... The tendency of women to push aside man, supplanting the old spirit of cooperation with him in all the affairs of life, is very disappointing to me." Although he told a reporter in later years that he sometimes felt that by not marrying, he had made too great a sacrifice to his work, Tesla chose to never pursue or engage in any known relationships, instead finding all the stimulation he needed in his work. Tesla was asocial and prone to seclude himself with his work. However, when he did engage in social life, many people spoke very positively and admiringly of Tesla.

Robert Underwood Johnson Robert Underwood Johnson (January 12, 1853 – October 14, 1937) was an American writer, poet, and diplomat. Biography Robert Underwood Johnson was born in Centerville, Indiana, on January 12, 1853. His brother Henry Underwood Johnson b ...

described him as attaining a "distinguished sweetness, sincerity, modesty, refinement, generosity, and force". His 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,

Julian Hawthorne Julian Hawthorne (June 22, 1846 – July 14, 1934) was an American writer and journalist, the son of novelist Nathaniel Hawthorne and Sophia Hawthorne, Sophia Peabody. He wrote numerous poems, novels, short stories, mysteries and detective f ...

, wrote, "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". Tesla was a good friend of Francis Marion Crawford, Robert Underwood Johnson,

Stanford White Stanford White (November 9, 1853 – June 25, 1906) was an American architect. He was also a partner in the architectural firm McKim, Mead & White, one of the most significant Beaux-Arts firms. He designed many houses for the rich, in addition ...

, Fritz Lowenstein, George Scherff, and Kenneth Swezey. In middle age, Tesla became a close friend of

; they spent a lot of time together in his lab and elsewhere. Twain notably described Tesla's

invention as "the most valuable patent since the telephone". At a party thrown by actress

Sarah Bernhardt Sarah Bernhardt (; born Henriette-Rosine Bernard; 22 or 23 October 1844 – 26 March 1923) was a French stage actress who starred in some of the most popular French plays of the late 19th and early 20th centuries, including ''La Dame Aux Cameli ...

in 1896, Tesla met Indian Hindu monk

Swami Vivekananda Swami Vivekananda (; ; 12 January 1863 – 4 July 1902), born Narendranath Datta (), was an Indian Hindu monk, philosopher, author, religious teacher, and the chief disciple of the Indian mystic Ramakrishna. He was a key figure in the intr ...

. Vivekananda later wrote that Tesla said he could demonstrate mathematically the relationship between matter and energy, something Vivekananda hoped would give a scientific foundation to Vedantic cosmology. The meeting with Swami Vivekananda stimulated Tesla's interest in Eastern Science, which led to Tesla studying Hindu and Vedic philosophy for a number of years. Tesla later wrote an article titled "Man's Greatest Achievenment" using sanskrit terms

akasha Akasha or Akash (Sanskrit ' ) means space or sky or æther in traditional Indian cosmology, depending on the religion. The term has also been adopted in Western occultism and spiritualism in the late 19th century. In many modern Indo-Aryan lan ...

and

prana In yoga, Indian medicine and Indian martial arts, prana ( sa2, प्राण, ; the Sanskrit word for breath, "life force", or "vital principle") permeates reality on all levels including inanimate objects. In Hindu literature, prāṇa is so ...

to describe the relationship between matter and energy. In the late 1920s, Tesla befriended George Sylvester Viereck, a poet, writer, mystic, and later, a

Nazi Nazism ( ; german: Nazismus), the common name in English for National Socialism (german: Nationalsozialismus, ), is the far-right totalitarian political ideology and practices associated with Adolf Hitler and the Nazi Party (NSDAP) in ...

propagandist. Tesla occasionally attended dinner parties held by Viereck and his wife. Tesla could be harsh at times and openly expressed disgust for overweight people, such as when he fired a secretary because of her weight. He was quick to criticize clothing; on several occasions, Tesla directed a subordinate to go home and change her dress. When

died, in 1931, Tesla contributed the only negative opinion to ''

'', buried in an extensive coverage of Edison's life:

Sleep habits

Tesla claimed never to sleep more than two hours per night. However, he did admit to "dozing" from time to time "to recharge his batteries". During his second year of study at

, Tesla developed a passionate proficiency for billiards,

chess Chess is a board game for two players, called White and Black, each controlling an army of chess pieces in their color, with the objective to checkmate the opponent's king. It is sometimes called international chess or Western chess to dist ...

, and card-playing, sometimes spending more than 48 hours in a stretch at a gaming table. On one occasion at his laboratory, Tesla worked for a period of 84 hours without rest. Kenneth Swezey, a journalist whom Tesla had befriended, confirmed that Tesla rarely slept. Swezey recalled one morning when Tesla called him at 3 a.m.: "I was sleeping in my room like one dead ... Suddenly, the telephone ring awakened me ... eslaspoke animatedly, with pauses, s henbsp;... work dout a problem, comparing one theory to another, commenting; and when he felt he had arrived at the solution, he suddenly closed the telephone."

Work and dining habits

Tesla worked every day from 9:00a.m. until 6:00p.m. or later, with dinner at exactly 8:10 p.m., at

restaurant and later the Waldorf-Astoria Hotel. Tesla then telephoned his dinner order to the headwaiter, who also could be the only one to serve him. "The meal was required to be ready at eight o'clock ... He dined alone, except on the rare occasions when he would give a dinner to a group to meet his social obligations. Tesla then resumed his work, often until 3:00a.m." For exercise, Tesla walked between per day. He curled his toes one hundred times for each foot every night, saying that it stimulated his brain cells. In an interview with newspaper editor Arthur Brisbane, Tesla said that he did not believe in telepathy, stating, "Suppose I made up my mind to murder you," he said, "In a second you would know it. Now, isn't that wonderful? By what process does the mind get at all this?" In the same interview, Tesla said that he believed that all fundamental laws could be reduced to one. Tesla became a vegetarian in his later years, living on only milk, bread, honey, and vegetable juices.

Views and beliefs

On experimental and theoretical physics

Tesla disagreed with the theory of atoms being composed of smaller

subatomic particle In physical sciences, a subatomic particle is a particle that composes an atom. According to the Standard Model of particle physics, a subatomic particle can be either a composite particle, which is composed of other particles (for example, a p ...

s, stating there was no such thing as an

electron The electron ( or ) is a subatomic particle with a negative one elementary electric charge. Electrons belong to the first generation of the lepton particle family, and are generally thought to be elementary particles because they have n ...

creating an electric charge. He believed that if electrons existed at all, they were some fourth state of matter or "sub-atom" that could exist only in an experimental vacuum and that they had nothing to do with electricity. Tesla believed that atoms are immutable—they could not change state or be split in any way. He was a believer in the 19th-century concept of an all-pervasive

ether In organic chemistry, ethers are a class of compounds that contain an ether group—an oxygen atom connected to two alkyl or aryl groups. They have the general formula , where R and R′ represent the alkyl or aryl groups. Ethers can again ...

that transmitted electrical energy. Tesla was generally antagonistic towards theories about the conversion of matter into energy. He was also critical of Einstein's

theory of relativity The theory of relativity usually encompasses two interrelated theories by Albert Einstein: special relativity and general relativity, proposed and published in 1905 and 1915, respectively. Special relativity applies to all physical phenomena in ...

, saying: In 1935 he described relativity as "a beggar wrapped in purple whom ignorant people take for a king" and said his own experiments had measured the speed of cosmic rays from Arcturus as fifty times the speed of light. Tesla claimed to have developed his own physical principle regarding matter and energy that he started working on in 1892, and in 1937, at age 81, claimed in a letter to have completed a "dynamic theory of gravity" that " ouldput an end to idle speculations and false conceptions, as that of curved space". He stated that the theory was "worked out in all details" and that he hoped to soon give it to the world. Further elucidation of his theory was never found in his writings.

On society

Tesla is widely considered by his biographers to have been a

humanist Humanism is a philosophical stance that emphasizes the individual and social potential and agency of human beings. It considers human beings the starting point for serious moral and philosophical inquiry. The meaning of the term "human ...

in philosophical outlook. This did not preclude Tesla, like many of his era, from becoming a proponent of an imposed

selective breeding Selective breeding (also called artificial selection) is the process by which humans use animal breeding and plant breeding to selectively develop particular phenotypic traits (characteristics) by choosing which typically animal or plant ...

version of

eugenics Eugenics ( ; ) is a fringe set of beliefs and practices that aim to improve the genetic quality of a human population. Historically, eugenicists have attempted to alter human gene pools by excluding people and groups judged to be inferior o ...

. Tesla expressed the belief that human "pity" had come to interfere with the natural "ruthless workings of nature". Though his argumentation did not depend on a concept of a "master race" or the inherent superiority of one person over another, he advocated for eugenics. In a 1937 interview he stated: In 1926, Tesla commented on the ills of the social subservience of women and the struggle of women toward

gender equality Gender equality, also known as sexual equality or equality of the sexes, is the state of equal ease of access to resources and opportunities regardless of gender, including economic participation and decision-making; and the state of valuing d ...

, and indicated that humanity's future would be run by "

Queen Bees ''Queen Bees'' is an eight-episode competition series produced by Endemol USA. It aired on The N from July 11 to August 29, 2008. The show brings a group of teen "queen bees" together to live under one roof. Through a series of challenges designed ...

". He believed that women would become the dominant sex in the future. Tesla made predictions about the relevant issues of a post-World War I environment in a printed article entitled "Science and Discovery are the great Forces which will lead to the Consummation of the War" (20 December 1914). Tesla believed that the

League of Nations The League of Nations (french: link=no, Société des Nations ) was the first worldwide intergovernmental organisation whose principal mission was to maintain world peace. It was founded on 10 January 1920 by the Paris Peace Conference th ...

was not a remedy for the times and issues.

On religion

Tesla was raised an Orthodox Christian. Later in life he did not consider himself to be a "believer in the orthodox sense", said he opposed religious fanaticism, and said "Buddhism and Christianity are the greatest religions both in number of disciples and in importance." He also said "To me, the universe is simply a great machine which never came into being and never will end" and "what we call 'soul' or 'spirit,' is nothing more than the sum of the functionings of the body. When this functioning ceases, the 'soul' or the 'spirit' ceases likewise."

Literary works

Tesla wrote a number of books and articles for magazines and journals. Among his books are '' My Inventions: The Autobiography of Nikola Tesla'', compiled and edited by Ben Johnston in 1983 from a series of 1919 magazine articles by Tesla which were republished in 1977; '' The Fantastic Inventions of Nikola Tesla'' (1993), compiled and edited by David Hatcher Childress; and ''The Tesla Papers''. Many of Tesla's writings are freely available online, including the article "The Problem of Increasing Human Energy", published in '' The Century Magazine'' in 1900, and the article "Experiments with Alternate Currents of High Potential and High Frequency", published in his book ''Inventions, Researches and Writings of Nikola Tesla''.

Legacy and honors

Tesla's legacy has endured in books, films, radio, TV, music, live theater, comics, and video games. The impact of the technologies invented or envisioned by Tesla is a recurring theme in several types of science fiction.

Things named after Tesla

Awards

* The Nikola Tesla Award

Enterprises and organizations

* Tesla, an electrotechnical conglomerate in the former Czechoslovakia *

Tesla, Inc Tesla, Inc. ( or ) is an American multinational automotive and clean energy company headquartered in Austin, Texas. Tesla designs and manufactures electric vehicles (electric cars and trucks), battery energy storage from home to grid ...

, an American electric car manufacturer * Nikola Motor Company, an American hydrogen and electric

class 8 truck Truck classifications are typically based upon the maximum loaded weight of the truck, typically using the gross vehicle weight rating (GVWR) and sometimes also the gross trailer weight rating (GTWR), and can vary among jurisdictions. United ...

manufacturer *

Ericsson Nikola Tesla Ericsson Nikola Tesla d.d. is the Croatian affiliate of the Swedish telecommunications equipment manufacturer Ericsson. The company is named after the inventor Nikola Tesla and is the largest specialized provider of modern telecommunications p ...

, Croatian affiliate of the Swedish

telecommunication Telecommunication is the transmission of information by various types of technologies over wire, radio, optical, or other electromagnetic systems. It has its origin in the desire of humans for communication over a distance greater than that ...

s equipment manufacturer

Ericsson (lit. "Telephone Stock Company of LM Ericsson"), commonly known as Ericsson, is a Swedish multinational networking and telecommunications company headquartered in Stockholm. The company sells infrastructure, software, and services in inform ...

Tesla Electric Light and Manufacturing Tesla Electric Light and Manufacturing Company was an electric lighting company in Rahway, New Jersey that operated from December 1884 through 1886. History Based at the site where 1571-1579 Irving Street now stands, on Irving Street between Co ...

* Tesla, an American rock band formed in Sacramento, California, in late 1982

Holidays and events

* Day of Science, Serbia, 10 July * Day of Nikola Tesla, Association of Teachers in

Vojvodina Vojvodina ( sr-Cyrl, Војводина}), officially the Autonomous Province of Vojvodina, is an autonomous province that occupies the northernmost part of Serbia. It lies within the Pannonian Basin, bordered to the south by the national capital ...

, 4–10 July * Day of Nikola Tesla, Niagara Falls, 10 July * Nikola Tesla Day in

Croatia , image_flag = Flag of Croatia.svg , image_coat = Coat of arms of Croatia.svg , anthem = " Lijepa naša domovino"("Our Beautiful Homeland") , image_map = , map_caption = , capi ...

, 10 July * Nikola Tesla annual electric vehicle rally in Croatia * In Ontario, Canada, the provincial legislature proclaimed 10 July as an annual recognition of his birth

Measures

* Tesla, an SI-derived unit of magnetic flux density (or magnetic inductivity)

Places

Nikola Tesla Memorial Center The Nikola Tesla Memorial Center is a cultural-historical site and museum located in Smiljan, Croatia, located at the birthplace of Nikola Tesla, one of the world's foremost engineers and inventors. It is dedicated to Tesla, who was born in 1 ...

in Smiljan,

Croatia , image_flag = Flag of Croatia.svg , image_coat = Coat of arms of Croatia.svg , anthem = " Lijepa naša domovino"("Our Beautiful Homeland") , image_map = , map_caption = , capi ...

Belgrade Nikola Tesla Airport Belgrade Nikola Tesla Airport ( sr, / ) or Belgrade Airport ( sr, / ) is an international airport serving Belgrade, Serbia. It is the largest and the busiest airport in Serbia, situated west of downtown Belgrade near the suburb of Su ...

Archive in

* Nikola Tesla Technical Museum in

Zagreb Zagreb ( , , , ) is the capital (political), capital and List of cities and towns in Croatia#List of cities and towns, largest city of Croatia. It is in the Northern Croatia, northwest of the country, along the Sava river, at the southern slop ...

, Croatia was named after the scientist in 2015 * TPP Nikola Tesla, the largest power plant in Serbia, first commissioned in 1970 * 128 streets in Croatia had been named after Nikola Tesla , making him the eighth most common street name origin in the country * Tesla, a 26 kilometer-wide crater on the far side of the moon *

2244 Tesla 2244 Tesla, provisional designation , is a carbonaceous asteroid from the central region of the asteroid belt, approximately 25 kilometers in diameter. It was discovered on 22 October 1952, by Serbian astronomer Milorad Protić at the Belgrade ...

, a minor planet

Schools

* Tesla STEM High School created in 2012 in

Redmond, Washington Redmond is a city in King County, Washington, United States, located east of Seattle. The population was 73,256 at the 2020 census, up from 54,144 in 2010. Redmond is best known as the home of Microsoft and Nintendo of America. With an ann ...

as a choice school with a focus on

STEM Stem or STEM may refer to: Plant structures * Plant stem, a plant's aboveground axis, made of vascular tissue, off which leaves and flowers hang * Stipe (botany), a stalk to support some other structure * Stipe (mycology), the stem of a mushro ...

subjects. The name was chosen by a student vote.

Ships

* SS ''Nikola Tesla'', a

Liberty Ship Liberty ships were a class of cargo ship built in the United States during World War II under the Emergency Shipbuilding Program. Though British in concept, the design was adopted by the United States for its simple, low-cost construction. Ma ...

laid down 31 August 1943, launched 25 September 1943, sold from government service in 1947, and scrapped in 1970

Plaques and memorials

Niagara-Falls ON Monument Nikola-Tesla 2015-08-13 (7)

* A monument to Tesla was established at

Niagara Falls, New York Niagara Falls is a city in Niagara County, New York, United States. As of the 2020 census, the city had a total population of 48,671. It is adjacent to the Niagara River, across from the city of Niagara Falls, Ontario, and named after the fame ...

. This monument portraying Tesla reading a set of notes was sculpted by

Frano Kršinić Frano Kršinić (24 July 1897 – 1 January 1982) was a Croatian sculptor active in former Yugoslavia. Along with Ivan Meštrović and Antun Augustinčić, he is considered one of the three most important Croatian sculptors of the 20th centur ...

. It was presented to the United States by Yugoslavia in 1976 and is an identical copy of the monument standing in front of the

University of Belgrade Faculty of Electrical Engineering The University of Belgrade School of Electrical Engineering also known as Faculty of Electrical Engineering ( sr, Електротехнички факултет Универзитета у Београду/''Elektrotehnički fakultet Univerziteta ...

. * A plaque depicting a relief of Nikola Tesla is present on the Old City Hall in

, Croatia's capital, commemorating his proposal to build an

power station A power station, also referred to as a power plant and sometimes generating station or generating plant, is an industrial facility for the generation of electric power. Power stations are generally connected to an electrical grid. Many ...

, which he made to the city council. The plaque quotes Tesla's statement, given in the building on 24 May 1892, which reads: "As a son of this country, I consider it my duty to help the City of Zagreb in every way, either through counsel or through action" ( hr, "Smatram svojom dužnošću da kao rođeni sin svoje zemlje pomognem gradu Zagrebu u svakom pogledu savjetom i činom"). * In July 2001, a commemorative plaque honoring Nikola Tesla was installed on the façade of the New Yorker Hotel by the

* The Nikola Tesla Memorial Centre in Smiljan, Croatia, opened in 2006. It features a statue of Tesla designed by sculptor Mile Blažević. * A monument of Tesla standing on a portion of an alternator was established at

Queen Victoria Park Queen Victoria Park is the main parkland located in Niagara Falls, Ontario, Canada opposite the American and Canadian Horseshoe Falls. Established by the Niagara Falls Park Act in 1885 and opened in 1888, the park is operated by the Niagara Par ...

Niagara Falls, Ontario Niagara Falls is a city in Ontario, Canada. It is on the western bank of the Niagara River in the Golden Horseshoe region of Southern Ontario, with a population of 88,071 at the Canada 2016 Census, 2016 census. It is part of the List of census ...

, 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,

, and designed by Les Drysdale of

Hamilton, Ontario Hamilton is a port city in the Canadian province of Ontario. Hamilton has a population of 569,353, and its census metropolitan area, which includes Burlington and Grimsby, has a population of 785,184. The city is approximately southwest of ...

. Drysdale's design was the winning design from an international competition. * On 7 July 2006, on the corner of Masarykova and Preradovićeva streets in the

Lower Town Lower Town (also spelled "Lowertown" (french: la Basse-Ville) is a neighbourhood in Rideau-Vanier Ward in central Ottawa, Ontario, Canada, to the east of downtown. It is the oldest part of the city. It is bounded by Rideau Street to the south, ...

area in Zagreb, a monument of Tesla was unveiled. This monument was designed by

Ivan Meštrović Ivan Meštrović (; 15 August 1883 – 16 January 1962) was a Croatian sculptor, architect, and writer. He was the most prominent modern Croatian sculptor and a leading artistic personality in contemporary Zagreb. He studied at Pavle Bilinić's ...

in 1952 and was transferred from the Zagreb-based Ruđer Bošković Institute where it had spent previous decades. * In 2012 Jane Alcorn, president of the nonprofit group

Tesla Science Center at Wardenclyffe The Tesla Science Center at Wardenclyffe (also known as TSCW) is a nonprofit organization established to develop a regional science and technology center, museum and makerspace at the site of Nikola Tesla's former Wardenclyffe laboratory on Lon ...

, and Matthew Inman, creator of web cartoon ''

The Oatmeal ''The Oatmeal'' is a webcomic and humor website created in 2009 by cartoonist Matthew Inman. It offers original comics, quizzes, and occasional articles. Inman has produced a series of ''Oatmeal'' books with content from the webcomic and previou ...

'', raised a total of $2,220,511 – $1,370,511 from a campaign and $850,000 from a New York State grant—to buy the property where Wardenclyffe Tower once stood and eventually turn it into a museum. The group began negotiations to purchase the

Long Island Long Island is a densely populated island in the southeastern region of the U.S. state of New York, part of the New York metropolitan area. With over 8 million people, Long Island is the most populous island in the United States and the 18 ...

property from Agfa Corporation in October 2012. The purchase was completed in May 2013. The preservation effort and history of Wardenclyffe is the subject of a documentary by Tesla activist/filmmaker Joseph Sikorski called ''Tower to the People—Tesla's Dream at Wardenclyffe Continues''. * A monument of Tesla was unveiled in

Baku Baku (, ; az, Bakı ) is the capital and largest city of Azerbaijan, as well as the largest city on the Caspian Sea and of the Caucasus region. Baku is located below sea level, which makes it the lowest lying national capital in the world an ...

in 2013. Presidents

Ilham Aliyev Ilham Heydar oghlu Aliyev ( az, İlham Heydər oğlu Əliyev, ; born 24 December 1961) is the fourth president of Azerbaijan, serving in the post since 31 October 2003. The son and second child of the former Azerbaijani leader Heydar Aliyev, ...

and

Tomislav Nikolić Tomislav Nikolić ( sr-Cyrl, Томислав Николић, ; born 15 February 1952) is a Serbian retired politician who served as the president of Serbia from 2012 to 2017. A former member of the far-right Serbian Radical Party (SRS), he di ...

attended a ceremony of unveiling. * A full-size, crowdfunded statue honoring Tesla with free Wi-Fi and a time capsule (to be opened on the 100th anniversary of Tesla's death, 7 January 2043) was unveiled on 7 December 2013 in Palo Alto, California (260 Sheridan Avenue) * An intersection named after Tesla, Nikola Tesla Corner, is located at

Sixth Avenue Sixth Avenue – also known as Avenue of the Americas, although this name is seldom used by New Yorkers, p.24 – is a major thoroughfare in New York City's borough of Manhattan, on which traffic runs northbound, or "uptown". It is commercial ...

and 40th Street, outside

Bryant Park Bryant Park is a public park located in the New York City borough of Manhattan. Privately managed, it is located between Fifth Avenue and Avenue of the Americas ( Sixth Avenue) and between 40th and 42nd Streets in Midtown Manhattan. Th ...

. The placement of the sign was due to the efforts of the Croatian Club of New York in cooperation with New York City officials, and Dr. Ljubo Vujovic of the Tesla Memorial Society of New York. * A bust and plaque honoring Tesla is outside the Serbian Orthodox Cathedral of Saint Sava (formerly known as Trinity Chapel) at 20 West 26th Street in New York City * Nikola Tesla Boulevard, Hamilton, Ontario

Computing

* Tesla, a

video card A graphics card (also called a video card, display card, graphics adapter, VGA card/VGA, video adapter, display adapter, or mistakenly GPU) is an expansion card which generates a feed of output images to a display device, such as a computer m ...

graphics processing unit microarchitecture developed by

Nvidia Nvidia CorporationOfficially written as NVIDIA and stylized in its logo as VIDIA with the lowercase "n" the same height as the uppercase "VIDIA"; formerly stylized as VIDIA with a large italicized lowercase "n" on products from the mid 1990s to ...

Currency

*The

Yugoslav dinar The dinar (Cyrillic script: динар) was the currency of the three Yugoslav states: the Kingdom of Yugoslavia (formerly the Kingdom of Serbs, Croats and Slovenes), the Socialist Federal Republic of Yugoslavia, and the Federal Republic of Yu ...

displayed Tesla on 6 different banknotes between 1970 (statue) and 1993 *Tesla is portrayed in the banknote of the 100 Serbian dinars *Tesla will be displayed on the Croatian 10, 20 and 50 cent coins when Croatia adopts the

euro The euro ( symbol: €; code: EUR) is the official currency of 19 out of the member states of the European Union (EU). This group of states is known as the eurozone or, officially, the euro area, and includes about 340 million citizens . ...

in 2023

Notes

Footnotes Citations

References

* * * * * * * * * * (reprinted 2007 by Book Tree, ) * * * *

External links

Nikola Tesla Museum

Tesla memorial society by his grand-nephew William H. Terbo

Tesla – References in European newspapers

Online archive of many of Tesla's writings, articles and published papers
*
Tesla Science Center at Wardenclyffe
* * *
U.S. patent 1,329,559

* ttp://edisontechcenter.org/tesladebunked.html Debunking the Tesla Myth (opinion piece) {{DEFAULTSORT:Tesla, Nikola 1856 births 1943 deaths 19th-century American engineers 20th-century American engineers 19th-century Serbian people 20th-century Serbian people American electrical engineers American eugenicists American futurologists American humanists American inventors American mechanical engineers Austro-Hungarian emigrants to the United States Austro-Hungarian engineers Austro-Hungarian inventors Serbian emigrants to the United States Serbian scientists Serbian engineers Serbian inventors Habsburg Serbs Austro-Hungarian Serbs Deaths from coronary thrombosis Fellow Members of the IEEE Fellows of the American Association for the Advancement of Science Grand Crosses of the Order of St. Sava Grand Crosses of the Order of the White Lion Graz University of Technology alumni Great Officers of the Order of St. Sava IEEE Edison Medal recipients Members of the Serbian Academy of Sciences and Arts Members of The Lambs Club Mental calculators Naturalized citizens of the United States People associated with electricity People from Colorado Springs, Colorado People from Gospić People from Karlovac People from Manhattan People of the Military Frontier Radio pioneers Recipients of the Order of the Yugoslav Crown Reputed virgins Serbs of Croatia Wireless energy transfer

Early years

Working at Budapest Telephone Exchange

Working at Edison

Moving to the United States

Tesla Electric Light & Manufacturing

AC and the induction motor

Market turmoil

New York laboratories

Tesla coil

Citizenship

Wireless lighting

Polyphase system and the Columbian Exposition

Steam-powered oscillating generator

Consulting on Niagara

The Nikola Tesla Company

Lab fire

X-ray experimentation

Radio remote control

Wireless power

Colorado Springs

Wardenclyffe

Later years

Bladeless turbine

Wireless lawsuits

Nobel Prize rumors

Other awards, patents and ideas

Living circumstances

Birthday press conferences

Death

Estate

Patents

Personal life and character

Appearance

Eidetic memory

Relationships

Sleep habits

Work and dining habits

Views and beliefs

On experimental and theoretical physics

On society

On religion

Literary works

Legacy and honors

Things named after Tesla

Awards

Enterprises and organizations

Holidays and events

Measures

Places

Schools

Ships

Plaques and memorials

Computing

Currency

See also

Notes

References

Further reading

External links