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PowerPedia:Nikola Tesla

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There was an error working with the wiki: Code[1] Also News:Nikola Tesla

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|+ style="font-size: larger" | Nikola Tesla


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! Birthplace and date

| 9 July / 10 July, 1856 Smiljan, Croatia [then part of Austrian Empire]


! Deathplace and date:

| ca., January 7, 1943 New York City, New York, USA


! Occupation:

| inventor, physicist, mechanical engineer and electrical engineer


! Ethnicity and nationality:

| Serbian-American


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Nikola Tesla was one of the most brilliant inventors of history and was of an unusual intellectual vision. He is affectionately refered to as the "Father of Free Energy". Tesla was a world-renowned Serbian-American inventor, physicist, mechanical engineer and electrical engineer, born in Smiljan, Austrian Empire (present day Croatia). Tesla is regarded as one of the most important inventors in history. He is also well known for his contributions to the discipline of electricity and magnetism in the late 19th and early 20th century. Directory:Tesla's Patent List and theoretical work form the basis of modern alternating current electric power (AC) systems, including the polyphase power distribution systems and the AC motor, with which he helped usher in the Second Industrial Revolution.

In the United States, Tesla's fame rivaled that of any other inventor or scientist in history or popular culture. After his demonstration of Directory:Wireless Transmission of Electricity communication in 1893 and after being the victor in the "War of Currents", he was widely respected as America's greatest electrical engineer. Much of his early work pioneered modern electrical engineering and many of his discoveries were of groundbreaking importance. In 1947, the United States Supreme Court credited him as being the inventor of the radio. Never putting much focus on his finances, Tesla died impoverished and forgotten at the age of 86.

Tesla's legacy can be seen across modern civilization wherever electricity is used. Aside from his work on electromagnetism and engineering, Tesla is said to have contributed in varying degrees to the fields of robotics, ballistics, computer science, nuclear physics, and theoretical physics. In his later years, Tesla was regarded as a mad scientist and became noted for making bizarre claims about possible scientific developments. Many of his achievements have been used, with some controversy, to support various pseudosciences, UFO theories, and New Age occultism. Many contemporary admirers of Tesla have deemed him the man who invented the twentieth century.

The following is quoted from

: Nikola Tesla, he with the giant intellect, one of the greatest inventors of all ages, the man who has brought forth the most amazing realities, always visualizes his inventions before attempting to work them out. He does not rush to embody them in form and then spend his time in correcting defects. Having first built up the idea in his imagination, he holds it there as a mental picture, to be reconstructed and improved by his thought. "In this way," he writes in the Electrical Experimenter, "I am enabled to rapidly develop and perfect a conception without touching anything. When I have gone so far as to embody in the invention every possible improvement I can think of, and see no fault anywhere, I put into concrete form the product of my brain. Invariably my device works as I conceived it should in twenty years there has not been a single exception."


: "When you look at Tesla's work -- and I've read all of his patents I've looked at all of his works in English and in German -- and in looking at Tesla, his big thing really boils down to one thing: resonance, harmony." -- Nick Begich, January 5, 2010

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|Tesla writing and research, from his patents to his theoretical work, provide thefoundation to the basis for modern industrial systems. Tesla ushered in the Second Industrial Revolution and his research continue to provide insights to innovation yet to be exploited. (Image from the Nikola Tesla Museum)


Tesla was of unusual intellectual brilliance. He had a general mental capability that could reason, plan, and solve problems in his head. He could think abstractly and comprehend ideas without putting pen to paper. His patents (over 100 in the United States) and theoretical work still form the basis for modern alternating current electric power systems (including the polyphase power distribution system). Tesla helped usher in the Second Industrial Revolution. Yet he hardly gets a footnote in our public school textbooks.

In his early years, he enjoyed widespread fame, a person who was widely recognized in a high society, and in culture. A large part of professional material of the publishing industries focuses on Tesla's announcements. He was highly regarded in the annuals of history. Tesla's name was a byword for innovation and practical achievement. His name was one of the most recognizable in the world, a magician who conjured up technical feats. Tesla's vision was to find a means to provide humanity the means for unlimited energy. He gave his life to make real these plans, while others made fortunes with his inventions.

Tesla is most famous for conceiving the rotating magnetic field principle (1882) and then using it to invent the induction motor together with the accompanying alternating current long-distance electrical transmission system (1888). His patents and theoretical work still form the basis for modern alternating current electric power(AC) systems including the polyphase power distribution system. He developed numerous other electrical and mechanical devices including the fundamental principles and machinery of Directory:Wireless Transmission of Electricity technology, the high frequency alternator, the "AND" logic gate and the Tesla coil, as well as other devices such as the bladeless turbine, devices for high voltage discharges, and the bifilar coil. He developed various devices that use rotating magnetic fields, the fundamental devices and systems of wireless communication (legal priority for the invention of radio), radio frequency oscillators, devices for voltage magnification by standing waves, robotics, devices for x-rays, and devices for ionized gases. Tesla later developed devices for high field emission, devices for charged particle beams, methods for providing extremely low level of resistance to the passage of electrical current, means for increasing the intensity of electrical oscillations, voltage multiplication circuitry, devices for lightning protection, and the VTOL aircraft.

Tesla toward the end of his life was regarded as a mad scientist. Tesla was mocked by his contemporaries and he wound up destitute and forgotten. Why is this? He wanted to distribute power freely to the entire globe, and he had the technology developed to do so. The problem with his proposal is that there would be no metering to make money off of each watt distributed -- no way to maintain control from the population. He was blacklisted from the mainstream. Although he was awarded hundred of patents worldwide, he died in poverty. A hundred years later, we are still playing catch-up. His legacy can been seen across modern civilization. Tesla was ahead of his time, many of Tesla's ideas and concepts are just only recently coming to fruition.

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Tesla was (and is) "the common man's Einstein". Real scientists mention him because his name is attached fundamentally to much of the underpinning of our modern society, to the induction coil, and a SI physical unit. The latter seems to have been adopted because of his varied and wide contributions to science and engineering in general. He identified the basic idea for the rotary induction motor, which was missed by others (in devices such as the 19th-century Wheatstone patent), and the basic circuit for the 'Tesla coil' (an improvement on more primitive circuit that can be seen in the 9th edition of Encyclopedia Britannica (circa 1860)). The history of modern radio dates to Tesla's work, as he consolidated and put into practical usefulness previous research. Among the reasons for his fame is that he was good at conveying ideas to the general public and businessmen who would then utilize this technology.


" The life story and work of Nikola Tesla. He invented AC electricity, Neon Lights, Radio transmission, The Electric motor, Wireless electricity transfer, Remote control, Hydraulics, Lasers, Space weapons, Robotics, and many, many more things." (YouTube October 28, 2007)

Early years


Tesla was born "at the stroke of midnight" in 1856 with lightning striking during a summer storm (the first moment of July 10). The midwife commented, "He'll be a child of the storm," to which his mother replied, "No, of light." He was born in Smiljan near Gospi? in Croatia, Lika, (the Military Frontier of the Austria-Hungary, now in Croatia). Smiljan is a village in the mountainous region of Lika, Croatia. It is located seven kilometers west of Gospi?, and fifteen kilometers from the highway Zagreb-Split its population is 446 (2001). Smiljan is known best for being the birthplace of Nikola Tesla on July 10, 1856. Nowdays, Tesla's birth house, together with the church and the surrounding area represents a memeorial complex with various exhibits of Tesla's inventions and a museum where the details of the discoverer's life are shown. There is also a congress hall in a nearby building.

Tesla's baptismal name was ?????? (Nikola). His Baptism Certificate reports that he was born on June 28 (Julian calendar July 10 in the Gregorian calendar) 1856. he was christened by the Serbian orthodox priest, Toma Oklobdžija. Tesla was baptised in the Old Slavonic Church rite.

His father was Rev. Milutin Tesla, a Serbian priest in the Orthodox Metropolitanate of Karlovci which gathered the Serbs of the "Greek-rite" as they were legally referred to in Habsburg Monarchy at the time (Vlach Orthodox Metropolitanate of Karlovci). His father's church in Gospi? was destroyed in the 1990s His mother was uka Mandi?, a housewife talented in making home craft tools. Nikola was one of five children, having one brother and three sisters. His godfather, Jovan Drenovac, was a Captain in the Krajina army. His family moved to Gospi? in 1862.

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|Tesla's education:



: Elementary school

:: Gospi&#263 (Austria-Hungary, now Croatia)

: Secondary school

:: Karlovac (Austria-Hungary, now Croatia)

: Undergraduate studies

:: Baccalaureate of Physics

:: Austrian Polytechnic Institute (Graz)

:: Baccalaureate of Mathematics

:: Austrian Polytechnic Institute (Graz)

:: Baccalaureate of Mechanical Engineering

:: Austrian Polytechnic Institute (Graz)

:: Baccalaureate of Electrical Engineering

:: Austrian Polytechnic Institute (Graz)

:Graduate studies

:: Physics

:: University of Prague (Prague)



Tesla went to school in Karlovac (then Austria-Hungary), then studied electrical engineering at the Austria Politechnic in Graz, Austria (1875). While there, he studied the uses of alternating current. In 1881 he moved to Budapest to work for the telegraph company, American Telephone Company. On the opening of the telephone exchange in Budapest, 1881, Tesla became the chief electrician to the company, later engineer to the Yugoslav government and the country's first telephone system. He also developed a telephone repeater (sometimes called an amplifier) [ed., this was one of the first wireless telephones]. The device could act as an audio speaker (not an audio transducer). Tesla was also fascinated by the Crookes radiometer, believeing that it was a most wonderful invention.


The device had its resonance tuned to a particular frequency of other repeaters to communicate between each. In 1916, Tesla described the prior developed audio transducers. According to Tesla, it was the:

: "... simplest ways [to detect the radiant energy ...] the low frequency gave audible notes. [... in a field, there was] placed a conductor, a wire or a coil, and then Tesla would get a note [...''] characteristics of the audible note".

The audible sounds were of the quality of the telephones diaphragms of that period of time. The invention was never patented nor released publicly (till years later by Tesla himself). The device also contained the characteristics of modern wireless telephones.

For a while he stayed in Maribor. He was employed at his first job as an assistant engineer. Tesla suffered a nervous breakdown during this time. In 1882 he moved to Paris to work as an engineer for the Continental Edison Company. He worked designing improvements to electric equipment. In the same year, Tesla conceived of the induction motor and began developing various devices that use rotating magnetic fields (for which he received patents in 1888). Tesla visualized the rotating fields and thereby designed the induction motor.

Tesla hastened from Paris to his mother's side as she lay dying, arriving hours before her death in 1882. Her last words to him were, "You've arrived, Nidzo, my pride." After her death, Tesla fell ill. He spent two to three weeks recuperating in Gospi? and the village of Tomingaj near Gra, the birthplace of his mother. All his life, Tesla kept a home-spun embroidered travel bag from his mother. [According to John J. O'Neill in his book "Prodigal Genius", Tesla's mother died in 1892. He rushed to her side not long after giving his famous lecture "Experiments with Alternating Currents of High Potential and High Frequency" delivered before the Institution of Electrical Engineers, London, February 1892. His father died sometime between 1878 and 1881.]

Coming to America

In 1884 Tesla moved to the United States of America to accept a job with the Edison Company in New York City. He arrived in the US with 4 cents to his name, a book of poetry, and a letter of recommendation from Charles Batchelor (his manager in his previous job) to Thomas Edison. The letter read simply "I know two great men, and you are one of them. This young man is the other". Tesla's work for Edison began with simple electrical engineering. Eventually Tesla earned the respect of Edison and offered to undertake a complete re-design of the Edison company's DC dynamos. After Tesla described the nature of the benefits from his proposed modifications, Edison offered him US$50,000 if they were successfully completed.

Tesla worked nearly a year to redesign them and gave the Edison company several enormously profitable new patents in the process. When Tesla inquired about the $50,000, Edison replied to him, "Tesla, you don't understand our American humor", and reneged on his agreement, offering a raise in Tesla's salary of $10 per week as a compromise - at which rate it would have taken almost 100 years to earn the money Edison had originally promised. Tesla resigned on the spot. In some accounts of the final confrontation, Tesla did not say a single word to Edison but simply turned his back on the inventor and walked off the premises. Edison would receive US patent 328572 for an improved commutator and, later, would gain US patent 373584 for a dynamo-electric machine (which includes an extra coil and utilizes a field of force) among other patents which Tesla may be responsible for.

In 1886, Tesla formed his own company, Tesla Electric Light & Manufacturing. The initial financial investors disagreed with Tesla on his plan for an alternating current motor and eventually relieved him of his duties at the company. Tesla worked in New York as a common laborer from 1886 to 1887 to feed himself and raise capital for his next project. In 1887, he constructed the initial brushless alternate-current induction motor, which he demonstrated to the American Institute of Electrical Engineers (now IEEE) in 1888. In the same year, he developed the principles of his Tesla coil and began working with George Westinghouse at Westinghouse Electric & Manufacturing Company's Pittsburgh labs. Westinghouse listened to his ideas for polyphase systems which would allow transmission of alternating current electricity over large distances.

War of the Currents

In the "War of Currents" era in the late 1880s, Nikola Tesla and Thomas Edison became adversaries due to Edison's promotion of direct current (DC) for electric power distribution over the more efficient alternating current (AC) advocated by Tesla. During the initial years of electricity distribution, Edison's direct current was the standard for the United States and Edison was not disposed to lose all his patent royalties. Direct current worked well for the incandescent lamps that were the principal load of the day. From his work with rotary magnetic fields, Tesla devised a system for generation, transmission, and use of AC power. He partnered with George Westinghouse to commercialize this system. Westinghouse had previously bought the rights to Tesla's polyphase system patents and other patents for AC transformers from Lucien Gaulard and John Dixon Gibbs.


Until Tesla invented the induction motor, AC's advantages for long distance high voltage transmission were counterbalanced by the inability to operate motors on AC. The direct current electric power transmission system had severe limitations that were solved by the use of alternating current. High loads of direct current could rarely be transmitted for distances of greater than one mile without introducing excessive voltage drops. The three-wire distribution system provided some improvement in voltage drop and conductor sizes, but did not eliminate the problem. Edison's response to the DC system limitations was to generate power close to where it was consumed (distributed generation) and install more wires to handle the growing demand for electricity, but this solution proved to be costly, impractical, and unmanageable.

Direct current could not easily be changed to higher or lower voltages. This meant that separate electrical lines had to be installed in order to supply power to appliances that use different voltages, for example, lighting and electric motors. This led to a greater number of wires to lay and maintain, wasting money and introducing unnecessary hazards. A number of deaths from the Great Blizzard of '88 were attributed to collapsing power lines that cluttered cities running DC power grids. High voltage AC could be transmitted over long distances with lower voltage drops (thus greater transmission efficiency), and then conveniently stepped down to low voltages for use in homes and factories. When Tesla introduced a system for alternating current generators, transformers, motors, wires, and lights in November and December of 1887, it became clear that AC was the future of electric power distribution.

Edison went on to carry out a campaign to discourage the use of alternating current. Edison personally presided over several executions of animals, primarily stray cats and dogs, to demonstrate to the press that his system of direct current was safer than that of alternating current. Edison's series of animal executions peaked with the electrocution of Topsy the Elephant. He also tried to popularize the term for being electrocuted as being "Westinghoused".

Edison opposed capital punishment, but his desire to disparage the system of alternating current led to the invention of the electric chair. Edison (or some of his employees) used AC to construct the first electric chair for the state of New York in order to promote the idea that alternating current was deadlier than DC. It is a popular belief, some would say misconception, that Edison alone invented the electric chair solely as a means of impressing the public that AC was more dangerous than DC, and would therefore be the logical choice for electrocutions. The chair was developed by a few of his employees, in particular Harold P. Brown, while working under Edison at Menlo Park.

When the chair was first used, the technicians on hand misjudged the voltage needed to kill the condemned prisoner, William Kemmler. The first jolt of electricity, delivered on August 6, 1890, was not enough to kill Kemmler, and left him only badly injured. The procedure had to be repeated and a reporter on hand described it as "an awful spectacle, far worse than hanging". George Westinghouse commented: "They would have done better using an axe." Low frequency (50 - 60 Hz) AC currents can be more dangerous than similar levels of DC current since the alternating fluctuations can cause the heart to lose coordination, inducing ventricular fibrillation, which then rapidly leads to death. However any practical distribution system will use voltage levels quite sufficient to ensure a dangerous amount of current will flow, whether it uses alternating or direct current. Since the precautions against electrocution are similar, ultimately, the advantages of AC power transmission outweighed this theoretical risk, and it was eventually adopted as the standard.

Harnessing Niagara

In 1883, the Niagara Falls Power Company, a descendant of Schoellkopf's firm, hired George Westinghouse to design a system to generate alternating current. When Tesla, for whom a memorial was later built at Niagara Falls, implemented the three-phase system of alternating current power transmission, distant transfer of electricity became possible. By 1896, with financing from moguls like J.P. Morgan, John Jacob Astor IV, and the Vanderbilts, they had constructed giant underground conduits leading to turbines generating upwards of 100,000 horsepower (75 MW), and were sending power as far as Buffalo, twenty miles (32 km) away. Private companies on the Canadian side also began to harness the energy of the Falls, employing both domestic and American firms in their efforts. The Government of Ontario eventually brought power transmission operations under public control in 1906, distributing Niagara's energy to various parts of that province. The water then passes through hydroelectric turbines that supply power to nearby areas of the United States and Canada before returning to the river well past the Falls. Some doubted that the system would generate enough electricity to power industry in Buffalo. Tesla was sure it would work, saying that Niagara Falls had the ability to power the entire eastern U.S. On November 16, 1896, electrical power was sent from Niagara Falls to industries in Buffalo from the hydroelectric generators at the Edward Dean Adams Station. The hydroelectric generators were built by Westinghouse Electric Corporation using Tesla's AC system patent. The nameplates on the generators bear Tesla's name. He also set the 60 hertz standard for North America. It took five years to complete the whole facility.

Middle years

High Frequency High Voltage

In April of 1887, Tesla began investigating what would later be called X-rays using his own single node vacuum tubes (similar to his There was an error working with the wiki: Code[4]). This device differed from other early X-ray tubes in that they had no target electrode. The modern term for the phenomenon produced by this device is bremsstrahlung (or braking radiation). We now know that this device operated by emitting electrons from the single electrode through a combination of field emission and thermionic emission. Once liberated, electrons are strongly repelled by the high electric field near the electrode during negative voltage peaks from the oscillating HV output of the Tesla Coil, generating X-rays as they collide with the glass envelope. He also used Geissler tubes. By 1892, Tesla became aware of what Wilhelm Röntgen later identified as effects of X-rays.

Tesla commented on the hazards of working with single node X-ray producing devices, incorrectly attributing the skin damage to ozone rather than the radiation:

: "As to the hurtful actions on the skin ... I note that they have been misinterpreted ... They are not due to the Röntgen rays, but merely to the ozone generated in contact with the skin. Nitrous acid may also be responsible, but to a small extent". (Tesla, in Electrical Review, 30 November 1895).

Tesla later observed an assistant severely "burnt" by X-rays in his lab. He performed several experiments (including photographing the bones of his hand later, he sent these images to Röntgen) but didn't make his findings widely known much of his research was lost in the 1895 Houston Street lab fire.


In the spring of 1891, Tesla gave demonstrations with various machines and coils before the American Institute of Electrical Engineers at Columbia College. Following the initial research of voltage and frequency by William Crookes, Tesla developed a series of coils that produced high-voltage, high-frequency currents. In the majority of Tesla's experiments, he used machinery of his own design to produce the Tesla effect. These early coils would use the "disruptive" action of a spark gap in their operation. The setup can be duplicated by a Ruhmkorff coil, two condensers (now called capacitors), and a second, specially constructed, disruptive coil.

In There was an error working with the wiki: Code[5], System of Electric Lighting (1891 June 23), Tesla described this early disruptive coil. It was devised for the purpose of converting and supplying electrical energy in a form suited for the production of certain novel electrical phenomena, which require currents of higher frequency and potential. It also specified an energy storage capacitor and discharger mechanism on the primary side of a radio-frequency transformer. This is the first-ever disclosure of a practical RF power supply capable of exciting an antenna to emit powerful electromagnetic radiation.

On July 30, 1891, he became a naturalized citizen of the United States at the age of 35. Tesla established his 35 South Fifth Avenue laboratory in New York during this same year. Later, Tesla would establish his Houston Street laboratory in New York at 46 E. Houston Street. He lit vacuum tubes wirelessly at both of the New York locations, providing evidence for the potential of wireless power transmission. Some of Tesla's closest friends were artists. He befriended Century Magazine editor Robert Underwood Johnson, who adapted several Serbian poems of Jovan Jovanovi? Zmaj (which Tesla translated). Also during this time, Tesla was influenced by the Vedic philosophy teachings of the Swami Vivekananda.

At the 1893 World's Fair, the World Columbian Exposition in Chicago, Illinois, an international exposition was held which for the first time devoted a building to electrical exhibits. It was a historic event as Tesla and George Westinghouse introduced visitors to AC power by using it to illuminate the Exposition. In protest, Thomas Edison would not allow use of any of his lightbulbs for this event (Westinghouse sidestepped this by developing a double-stopper lamp). On display were Tesla's fluorescent lights and single node bulbs. As if lighting the Exposition was not enough, Tesla explained the principles of the rotating magnetic field and induction motor by demonstrating how to make an egg (made of copper) stand on end in his demonstration of the device he constructed known as the "Egg of Columbus". It was used to demonstrate and explain the model principles of a magnetic vortex field and the induction motor


The World's Columbian Exposition (also called The Chicago World's Fair), a World's fair, was held in the U.S. city of Chicago in 1893 to celebrate the 400th anniversary of Christopher Columbus' discovery of the New World. Chicago bested New York City, Washington, D.C., and St. Louis, Missouri, for the honor of hosting the fair. The fair had a profound effect on architecture, the arts, Chicago's self image, and American industrial optimism. The International Exposition was held in a building which for the first time was devoted to electrical exhibits. It was a historical moment and the beginning of a revolution, as Nikola Tesla and George Westinghouse introduced the public to electrical power by providing alternating current to illuminate the Exposition. The general public observed firsthand the qualities and abilities of alternating current power. All the exhibits were from commercial enterprises. Thomas Edison, Brush, Western Electric, and Westinghouse had exhibits. General Electric Company (backed by Edison and J.P. Morgan) proposed to power the electric fair with direct current at the cost of one million dollars.

Westinghouse, armed with Tesla's alternating current system, proposed to illuminate the exposition for half that price. Tesla's high-frequency high-voltage lighting produced more efficient light with quantitatively less heat. A two-phase induction motor was driven by current from the main generators to power the system. Edison tried to prevent the use of his light bulbs in Tesla's works. Westinghouse's proposal was chosen over the less efficient (but safer) direct current system to power the fair. General Electric banned the use of Edison's lamps in Westinghouse's plan, in retaliation for losing the bid. Westinghouse's company quickly designed a double-stopper lightbulb (sidestepping Edison's patents) and was able to light the fair.

The Westinghouse Company displayed several polyphase systems. The exhibits included a switchboard, polyphase generators, step-up transformers, transmission line, step-down transformers, commercial size induction motors and synchronous motors, and rotary direct current converters (including an operational railway motor). The working scaled system allowed the public a view of a system of polyphase power which could be transmitted over long distances, and be utilized, including the supply of direct current. Meters and other auxiliary devices were also present. Tesla displayed his phosphorescent lighting, powered without wires by high-frequency fields. Tesla displayed the first practical phosphorescent lamps (a precursor to fluorescent lamps). Tesla's lighting inventions exposed to high-frequency currents would bring the gases to incandescence. Tesla also displayed the first neon lights. His innovations in this type of light emission were not regularly patented.


Also among the exhibits was Tesla's demonstration, most notably the "Egg of Columbus". This device explains the principles of the rotating magnetic field and his induction motor. The Egg of Columbus consisted of a polyphase field coil underneath a plate with a copper egg positioned over the top. When the sequence of coils were energized, the magnetic field arrangement inductively created a rotation on the egg and made it stand up on end (appearing to resist gravity). On August 25, Elisha Gray introduced Tesla for a delivery of a lecture on mechanical and electrical oscillators. Tesla explained his work for efficiently increasing the work at high frequency of reciprocation. As Electrical Congress members listened, Tesla delineated mechanisms which could produce oscillations of constant periods irrespective of the pressure applied and irrespective of frictional losses and loads. He continued to explain the working mean of the production of constant period electric currents (not resorting to spark gaps or breaks), and how to produce these with mechanisms which are reliable. The successful demonstration of alternating current lighting at the Exposition dispelled doubts about the usefulness of the polyphase alternating current system developed by Westinghouse and Tesla.

Tesla's AC replaced DC in many instances of generation and power distribution, enormously extending the range and improving the safety and efficiency of power distribution. Edison's inventions using DC ultimately lost to AC devices proposed by others: primarily Tesla's polyphase systems, and also other contributors, such as Charles Proteus Steinmetz (of General Electric). Tesla's Niagara Falls system marked the end of Edison's roadmap for electrical transmission and was a turning point in the acceptance of alternating current. Eventually, Edison's General Electric company converted to the AC system and began manufacture of AC machines. As a result of the "War of Currents," Edison and Westinghouse were almost bankrupt, so in 1897, Tesla released Westinghouse from contract, providing Westinghouse a break from Tesla's patent royalties. Also in 1897, Tesla researched radiation which led to setting up the basic formulation of cosmic rays.

When Tesla was 36 years old, the first patents concerning the polyphase power system were granted. He continued research of the system and rotating magnetic field principles. Tesla served as the vice president of the American Institute of Electrical Engineers (now part of the IEEE) from 1892 to 1894. From 1893 to 1895, he investigated high frequency alternating currents. He generated AC of one million volts using a conical Tesla coil and investigated the skin effect in conductors, designed tuned circuits, invented a machine for inducing sleep, cordless gas discharge lamps, and transmitted electromagnetic energy without wires, effectively building the first radio transmitter. In St. Louis, Missouri, Tesla made a demonstration related to radio communication in 1893. Addressing the Franklin Institute in Philadelphia, Pennsylvania and the National Electric Light Association, he described and demonstrated in detail its principles. Tesla's demonstrations were written about widely through various media outlets.


Another early Tesla coil was protected in 1897 by There was an error working with the wiki: Code[6], "Electrical Transformer". This transformer developed (or converted) currents of high potential and was comprised of a primary and secondary coil (optionally, one terminal of the secondary could be electrically connected with the primary similar to modern ignition coils). This Tesla coil had the secondary being inside of, and surrounded by, the convolutions of the primary coil. This Tesla coil comprised of a primary and secondary wound in the form of a flat spiral. One coil, the secondary in step up transformation, of the device consisted of a longer fine-wire. The apparatus was also connected to the Earth when the coil was in use.

Also when Tesla was 41 years old, he filed the first basic radio patent (There was an error working with the wiki: Code[7]). A year later, Tesla devised an "electric igniter" or spark plug for Internal combustion gasoline engines. He gained U.S. Patent 609250, "Electrical Igniter for Gas Engines", on this mechanical ignition system. Tesla lived in the former Gerlach Hotel, renamed The Radio Wave building, at 49 W 27th St.(between Broadway and Sixth Avenue), Lower Manhattan, before the end of the century where he conducted the radio wave experiments. A commemorative plaque was placed on the building in 1977 to honor his work.

Robots and Telautomatics

In 1897 , he demonstrated a radio controlled boat to the US military, believing that the military would want things such as radio controlled torpedoes. Tesla developed the "Art of Telautomatics", a form of robotics. In 1898, a radio-controlled boat was demonstrated to the public during an electrical exhibition at Madison Square Garden. These devices had an innovative coherer and a series of logic gates. Radio remote control remained a novelty until the 1960s.

Colorado Springs, Colorado

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

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


Tesla, a local contractor, and several assistants commenced the construction of the laboratory shortly after arriving in Colorado Springs. The lab was established on Knob Hill, east of the Colorado School for the Deaf and Blind and one mile (1.6 km) east of downtown. Its primary purposes were experiments with high frequency electricity and other phenomena and, secondarily, research into Directory:Wireless Transmission of Electricity transmission of electrical power. Tesla's design of the lab was a building fifty feet by sixty feet (15 by 18 m) with eighty-foot (24 m) ceilings. A one-hundred-forty-two foot (43 m) conducting aerial with a thirty-inch (76 cm) copper-foil covered wooden ball was erected on the roof. The roof was rolled back to prevent fire from sparks and other dangerous effects of the experiments. The laboratory had sensitive instruments and equipment.

The lab possessed the largest Tesla Coil ever built, fifty-two feet (16 m) in diameter, known as the Magnifying Transmitter. Not identical to a classic Tesla Coil, it was a three-coil magnifying system requiring different forms of analysis than lumped-constant coupled resonant coils presently described to most. It resonated at a natural quarter wavelength frequency and could work in a continuous-wave mode and in a partially damped-wave resonant mode. According to accounts, Tesla used it to transmit tens of thousands of watts of power wirelessly it could generate millions of volts of electricity and produce lightning bolts more than one-hundred feet (30 m) long. At his lab, Tesla proved that the earth was a conductor, and he produced artificial lightning (with discharges consisting of millions of volts, and up to 135 feet long). Tesla posted a large fence around it with a sign "Keep Out - Great Danger".

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

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Reproductions of Tesla's receivers and coherer circuits show an unpredicted level of complexity (e.g., distributed high-Q helical resonators, radio frequency feedback, crude heterodyne effects, and regeneration techniques). Tesla also constructed many smaller resonance transformers and discovered the concept of tuned electrical circuits. He also developed a number of coherers for separating and perceiving electromagnetic waves and designed rotating coherers which he used to detect the unique types of electromagnetic phenomenon he observed. They had a mechanism of geared wheels driven by a coiled spring-drive mechanism which rotated small glass cylinders. These experiments were the final stage of years of work on synchronized tuned electrical circuits.

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


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

The investigations of atmospheric electricity involved observing lightning signals via his receivers. Tesla stated that he observed stationary waves during this time. Tesla conducted experiments contributing to the understanding of electromagnetic propagation and the Earth's resonance. It is well documented (from various photos from the time) that he lit hundreds of lamps wirelessly at a distance of up to twenty-five miles (40 km). He transmitted signals several kilometres and lit neon tubes conducting through the ground. He researched ways to transmit energy wirelessly over long distances (utilizing the ionosphere and the ground's telluric currents via transverse waves, to a lesser extent, and, more readily, longitudinal waves). He transmitted extremely low frequencies through the ground as well as between the earth's surface and the Kennelly-Heaviside layer. He recieved patents on wireless that developed standing waves by this method. In his experiments, he made mathematical calculations and computations based on his experiments and discovered that the resonant frequency of the Earth was approximately 8 Hz (Hertz). In the 1950s, researchers confirmed resonant frequency was in this range (interesting to note, Theta brain waves also cycle in this range).

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

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

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

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

Tower of Dreams

Tesla left Colorado Springs on January 7, 1900. The lab was torn down, broken up, and its contents sold to pay debts. The Colorado experiments prepared Tesla for his next project, the establishment of a wireless power transmission facility that would be known as Wardenclyffe. On March 21, 1900, Tesla was granted US685012 patent for the means for increasing the intensity of electrical oscillations. The United States Patent Office classification system currently assigns this patent to the primary Class 178/43 ("telegraphy/space induction"), although the other applicable classes include 505/825 ("low temperature superconductivity-related apparatus"). A few years later, George Westinghouse and J. P. Morgan stopped funding Tesla's research when Tesla showed him that he could offer free electricity to the whole world by simply "ramming a stick in the earth in your backyard". Westinghouse said he would go bankrupt if that happened.

Image:BrochureWardenclyffe .png

Nikola Tesla began planning the Wardenclyffe Tower facility ca. 1898, and in 1901, construction began on the land near Long Island Sound. Architect Stanford White designed the Wardenclyffe facility main building. The tower was designed by W.D. Crow, an associate of White. Funding for Tesla's project was provided by influential industrialists and other venture capitalists. The project was initially backed by the wealthy J. P. Morgan (he had a substantial investment in the facility, initially investing $150,000).

In June 1902, Tesla moved his laboratory operations from his Houston Street laboratory to Wardenclyffe. However, in 1903, when the tower structure was near completion, it was still not yet functional due to last-minute design changes that introduced in an unintentional defect. When Morgan wanted to know "Where can I put the meter?", Tesla had no answer. Tesla's vision of free power did not agree with Morgan's worldview. Construction costs eventually exceeded the money provided by Morgan, and additional financiers were reluctant to come forth. By July 1904, Morgan (and the other investors) finally decided they would not provide any additional financing. Morgan also encouraged other investors to avoid the project. In 1904, the US Patent Office reversed its decision and awarded Guglielmo Marconi the patent for radio. Tesla began his fight to re-acquire his radio patent. Later in 1907, Marconi was awarded the Nobel Prize for radio. Tesla was deeply resentful. So in 1915, Tesla filed a lawsuit against Marconi. In May 1905, Tesla's patents on alternating current motors and other methods of power transmission expired, halting royalty payments and causing a severe reduction of funding to the Wardenclyffe Tower. In an attempt to find alternative funding, Tesla advertised the services of the Wardenclyffe facility, but he met with little success. By this time, Tesla had also designed the Tesla turbine at Wardenclyffe and produced Tesla coils for sale to various businesses.

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Who Invented Radio?
Image:Nikola Tesla.jpg

Tesla always disputed the claim that Marconi invented radio and he gave a simple reason for this position. It was that radio is not an invention:

: "It was evident to me in 1888 that wireless transmission of energy, if it could ever be accomplished, is not an invention it is an art. Bell's telephone, Edison's phonograph, or my induction motor were inventions, but the wireless transmission of energy is an art that requires a great many inventions in combination.", (Nikola Tesla, 1916, in Ed. Anderson, Leland, 'Nikola Tesla On His Work With Alternating Currents And Their Application to Wireless Telegraphy, Telephony, and Transmission of Energy, Published 1992.

Seen in this context, some believe that it is Tesla's lecture and patent record from 1888 onwards that contains the fundamental information on the '... great many inventions ...' that form the basis for modern radio and wireless technology.

By 1905, since Tesla could not find any more backers, most of the site's activity had to be shut down. The main hall continued to be used for blackface minstrel shows until October of that year. Employees were laid off in 1906, but parts of the building remained in use until 1907. In 1908, the property was foreclosed for the first time. Tesla procured a new mortgage from the proprietor of the Waldorf-Astoria Hotel, George C. Boldt. The facility was partially abandoned around 1911, the tower structure eventually becoming deteriorated. Between 1912 and 1915, Tesla's finances unraveled, and when the funders wanted to know how they were going to recapture their investments, Tesla was unable to give satisfactory answers. Newspaper headlines of the time labeled it "Tesla's million-dollar folly." The facility's main building was breached and vandalized around this time. Collapse of the Wardenclyffe project may have contributed to the mental breakdown Tesla experienced during this period. Coupled to the personal tragedy of Wardenclyffe was the earlier 1895 unexplained fire in Tesla's Houston Street laboratory. In this fire, he lost much of his equipment, notes and documents. This produced a state of severe depression for Tesla.

In 1915, legal ownership of the Wardenclyffe property was transferred to George Boldt for a $20,000 debt. Demolition (reportedly by the U.S. Govt.) and salvaging of the tower occurred in 1917. However, the main building remains standing to this day. Tesla was not in New York during the tower's destruction. George Boldt wished to make the property available for sale. New York papers reported that the tower had been destroyed by order of the government to prevent its use by foreign agents. In 1917, the United States government may have aided the destruction of the Wardenclyffe Tower, ostensibly because it was believed it could provide a navigational landmark for German submarines. Neither claim is known to have been substantiated. On April 20, 1922 Tesla lost an appeal of judgment versus his backers in the second foreclosure. This effectively locked Tesla out of any future development of the facility.

In 1915, Tesla filed a lawsuit against Marconi attempting, unsuccessfully, to obtain a court injunction against the claims of Marconi. Around 1916, Tesla filed for bankruptcy because he owed so much in back taxes. He was living in poverty. After Wardenclyffe, Tesla built the Telefunken Wireless Station in Sayville, Long Island. Some of what he wanted to achieve at Wardenclyffe was accomplished with the Telefunken Wireless. In 1917, the facility was seized and torn down by the Marines, because it was suspected that it could be used by German spies.

In the ongoing lawsuit regarding the patent battle was finally resolved in Tesla's favor in 1944, one year after his death. This decision was based on the facts of the prior work existing before the establishment of Marconi's patent. At the time, the United States Army was involved in a patent infringement lawsuit with Marconi regarding radio, leading some to posit that the government granted Tesla and others the formal recognition in order to nullify any claims Marconi would have to compensation (as the earlier award to Marconi nullified any claims Tesla would have had for compensation).

Since the Nobel Prize in Physics was awarded to Marconi for radio in 1909, Thomas Edison and Tesla were mentioned as potential laureates to share the Nobel Prize of 1915 in an press dispatch, leading to one of several Nobel Prize controversies. It was believed that due to their animosity toward each other neither was given the award, despite their enormous scientific contributions. There is some indication that each sought to minimize the other one's achievements and right to win the award, that both refused to ever accept the award if the other received it first, and that both rejected any possibility of sharing it, as was rumour in the press at the time. In the following events after the rumors, neither Tesla nor Edison won the prize (although Edison did receive one of 38 possible bids in 1915, and Tesla did receive one bid out of 38 in 1937). Earlier, Tesla alone was rumored to the Nobel Prize of 1912. The rumored nomination for the 1912 Nobel Prize was primarily for his experiments with tuned circuits using high-voltage high-frequency resonant transformers. It was possible that Tesla was told of the plans of the physics award committee and let it be known that he would not share the award with Edison.

Turbines and pumps

On his 50th birthday in 1906, Tesla demonstrated his 200 hp (150 kW) 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 100-5000 hp. The Tesla turbine's bladeless design patented by Tesla in 1913. It is referred to as a bladeless turbine because it utilizes the boundary layer effect and not by a fluid impacting the blades in a conventional turbine. The Tesla turbine is also known as the boundary layer turbine, cohesion-type turbine, bladeless turbine, and Prandtl layer turbine (after Ludwig Prandtl).

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Later years

World War I to World War II

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

Tesla started to exhibit pronounced symptoms of obsessive-compulsive disorder in the years following. He became obsessed with the number three. He often felt compelled to walk around a block three times before entering a building, demanded a stack of three folded cloth napkins beside his plate at every meal, etc. The nature of OCD was little understood at the time and no treatments were available, so his symptoms were considered by some to be evidence of partial insanity and this probably hurt what was left of his reputation. This obsessive-compulsive behavior may have originated from the observations over repeated polyphase systems in nature that Tesla researched. Referencing Tesla's developing obsessive-compulsive disorder, it has been concretely demonstrated that obsessive-compulsive disorder, once thought to be a mental illness, has conclusively been proven to be a physical illness. The origins may be viral in nature, perhaps related to a weakened immune system. Connecting his illness to his exposure to work may indeed be correct.


At this time, he was staying at the Waldorf-Astoria Hotel, renting in an arrangement for deferred payments. Eventually, the Wardenclyffe deed was turned over to George Boldt, proprietor of the Waldorf-Astoria to pay a $20,000 debt. In 1917, around the time that the Wardenclyffe Tower was demolished by Boldt to make the land a more viable real estate asset, Tesla received AIEE's highest honor, the Edison Medal. The irony of this honor was probably not lost on Tesla.

Tesla, in August 1917, first established principles regarding frequency and power level for the first primitive radar units in 1934. Emile Girardeau, working with the first French radar systems, stated he was building radar systems "conceived according to the principles stated by Tesla". By the twenties, Tesla was reportedly negotiating with the United Kingdom government under Prime Minister Chamberlain about a ray system. Tesla had also stated that efforts had been made to steal the "death ray" (though they had failed). The Chamberlain government was removed, though, before any final negotiations occurred. The incoming Baldwin government found no use for Tesla's suggestions and ended negotiations. In 1925, the property ownership of Wardenclyffe was transferred to Walter L. Johnson of Brooklyn.

On Tesla's seventy-fifth birthday in 1931, Time magazine put him on its cover. The cover caption noted his contribution to electrical power generation. In 1935, many of Marconi's patents relating to the radio were declared invalid by the United States Court of Claims. The Court of Claims decided that the prior work of Tesla (specifically There was an error working with the wiki: Code[8] and There was an error working with the wiki: Code[9]) had anticipated Marconi's later works. Tesla got his last patent in 1928 on January 3, an apparatus for aerial transportation which was the first instance of VTOL aircraft. In 1934, Tesla wrote to consul Jankovi? of his homeland. The letter contained the message of gratitude to Mihajlo Pupin who initiated a donation scheme by which American companies could support Tesla. Tesla refused the assistance, and chose to live by a modest pension received from Kingdom of Yugoslavia and to continue researching.

Tesla's Pierce-Arrow

Of all the legends about Tesla, one of the most intriguing is that he ran a touring sedan on a little black box, extracting energy freely somehow from the wheelwork of nature, requiring no petrol. Tesla's Pierce-Arrow reportedly had a 80-horsepower alternating-current electric motor with no external power source. The driving circuit was composed of 12 vacuum tubes, some wires and assorted resistors. Tesla reportedly test drove the car for a week, with speed up to 90 mph. On March 6, 1939, Plantacres, Inc. purchased the facility's land and subsequently leased it to Peerless Photo Products, Inc. (which was subsequently bought out by AGFA Corporation, the current owner).

A Weapon to End War

Later in life, Tesla made some remarkable claims concerning a "teleforce" weapon. The press called it a "peace ray" or death ray. In total, the components and methods included:

An apparatus for producing manifestations of energy in free air instead of in a high vacuum as in the past. This, according to Tesla in 1934, was accomplished.

A mechanism for generating tremendous electrical force. This, according to Tesla, was also accomplished.

A means of intensifying and amplifying the force developed by the second mechanism.

A new method for producing a tremendous electrical repelling force. This would be the projector, or gun, of the invention.

Tesla worked on plans for a There was an error working with the wiki: Code[11] between the early 1900s till the time of his death. In 1937, Tesla composed a treatise entitled "The Art of Projecting Concentrated Non-dispersive Energy through the Natural Media" concerning charged particle beam. Tesla published the document in an attempt expound on the technical description of a "superweapon that would put an end to all war". This treatise of the particle beam is currently in the Nikola Tesla Museum archive in Belgrade. It described an open ended vacuum tube with a gas jet seal that allowed particles to exit, a method of charging particles to millions of volts, and a method of creating and directing nondispersive particle streams (through electrostatic repulsion). Records of his indicate that it was based on a narrow stream of atomic clusters of liquid mercury or tungsten accelerated via high voltage (by means akin to his magnifying transformer). Tesla gave the following description concerning the particle gun's operation:

: [The nozzel would] "send concentrated beams of particles through the free air, of such tremendous energy that they will bring down a fleet of 10,000 enemy airplanes at a distance of 200 miles from a defending nation's border and will cause armies to drop dead in their tracks".

The weapon could be used against ground based infantry or for antiaircraft purposes. Tesla tried to interest the US War Department in the device. He also offered this invention to European countries. None of the governments purchased a contract to build the device. He was unable to act on his plans.