Nikola Tesla

[Lynn Rotanno]

In April 1887, Tesla began investigating what would later be called X-rays using his own single node vacuum tubes (similar to his patent #514,170). 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 electron emission and thermionic emission. Once liberated, electrons are strongly repelled by the high electric field near the electrode during negative voltage peaks from the oscillating HV output of the Tesla Coil, generating X-rays as they collide with the glass envelope. He also used Geissler tubes. By 1892, Tesla became aware of the skin damage that Wilhelm Röntgen later identified as an effect of X-rays.

[Lynn Rotanno]

In the early research, Tesla devised several experimental setups to produce X-rays. Tesla held that, with his circuits, the "instrument will [... enable one to] generate Roentgen rays of much greater power than obtainable with ordinary apparatus".[47] He also commented on the hazards of working with his circuit and single node X-ray producing devices. Of his many notes in the early investigation of this phenomenon, he attributed the skin damage to various causes. One of the options for the cause, which is not in conformity with conventional X-ray production, was that the ozone generated rather than the radiation was responsible. He believed early on that damage to the skin was not due to the Roentgen rays, but the ozone generated in contact with the skin, and to a lesser extent, nitrous acid. Tesla held that these were in fact longitudinal waves, such as those produced in waves in plasma. In a plasma or a confined space, there can exist waves which are either longitudinal or transverse, or a mixture of both. There are known examples of this and these plasma waves can occur in the situation of force-free magnetic fields.[48][49] His hypotheses and experiments were confirmed by others.[50]

[Lynn Rotanno]

Tesla continued research in the field and, later, observed an assistant severely "burnt" by X-rays in his lab. He performed several experiments prior to Roentgen's discovery (including photographing the bones of his hand; later, he sent these images to Roentgen) but didn't make his findings widely known; much of his research was lost in the 5th Avenue lab fire of March 1895.

A "world system" for "the transmission of electrical energy without wires" that depends upon the electrical conductivity was proposed in which transmission in various natural media with current that passes between the two points are used to power devices. In a practical wireless energy transmission system using this principle, a high-power ultraviolet beam might be used to form a vertical ionized channel in the air directly above the transmitter-receiver stations. The same concept is used in virtual lightning rods, the electrolaser electroshock weapon,[51] and has been proposed for disabling vehicles.[52][53]

[Lynn Rotanno]

Tesla demonstrated "the transmission of electrical energy without wires" that depends upon electrical conductivity as early as 1891. The Tesla effect (named in honor of Tesla) is the archaic term for an application of this type of electrical conduction (that is, the movement of energy through space and matter; not just the production of voltage across a conductor).[22]:174[54]

[Lynn Rotanno]

On 30 July 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. There, at one point while conducting mechanical resonance experiments with electro-mechanical oscillators he generated a resonance of several surrounding buildings but, due to the frequencies involved, not his own building, causing complaints to the police. As the speed grew he hit the resonant frequency of his own building and, belatedly realizing the danger, he was forced to apply a sledgehammer to terminate the experiment, just as the astonished police arrived.[55] He also lit vacuum tubes wirelessly at both of the New York locations, providing evidence for the potential of wireless power transmission.[56]

Some of Tesla's closest friends were artists. He befriended Century Magazine editor Robert Underwood Johnson, who adapted several Serbian poems of Jovan Jovanović Zmaj (which Tesla translated). Also during this time, Tesla was influenced by the Vedic philosophy teachings of the Swami Vivekananda.[57]

[Lynn Rotanno]

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. It is curious that Nikola Tesla, a pioneer of AC systems, was born approximately 100 km north of Šibenik where the first power plant in Croatia was constructed. It may be a coincidence that in May 1892, Tesla held a lecture on alternating systems in the City Hall of Zagreb (the capital of Croatia) at the time of the beginning of the preparations to construct the Jaruga I hydroelectric power plant.[58] Tesla served, from 1892 to 1894, as the vice president of the American Institute of Electrical Engineers, the forerunner (along with the Institute of Radio Engineers) of the modern-day IEEE. From 1893 to 1895, he investigated high frequency alternating currents. He generated AC of one million volts using a conical Tesla coil and investigated the skin effect in conductors, designed tuned circuits, invented a machine for inducing sleep, cordless gas discharge lamps, and transmitted electromagnetic energy without wires, building the first radio transmitter. In St. Louis, Missouri, Tesla made a demonstration related to radio communication in 1893. Addressing the Franklin Institute in Philadelphia, Pennsylvania and the National Electric Light Association, he described and demonstrated in detail its principles. Tesla's demonstrations were written about widely through various media outlets. Tesla also investigated harvesting energy that is present throughout space. He believed that it was just merely a question of time when men will succeed in attaching their machinery to the very wheelwork of nature, stating:

[Lynn Rotanno]

“    Ere many generations pass, our machinery will be driven by a power obtainable at any point of the universe.    ”

_{—"Experiments With Alternate Currents Of High Potential And High Frequency" (February 1892)}

[Lynn Rotanno]

At the 1893 World's Fair, the World's Columbian Exposition in Chicago, an international exposition was held which for the first time devoted a building to electrical exhibits. It was a historic event as Tesla and George Westinghouse introduced visitors to AC power by using it to illuminate the Exposition. On display were Tesla's fluorescent lamps and single node bulbs. An observer noted:

    _{Within the room was suspended two hard-rubber plates covered with tin foil. These were about fifteen feet apart, and served as terminals of the wires leading from the transformers. When the current was turned on, the vacuum bulbs or tubes, which had no wires connected to them, but lay on a table between the suspended plates, or which might be held in the hand in almost any part of the room, were made luminous. These were the same experiments and the same apparatus shown by Mr. Tesla in London about two years ago, where they produced so much wonder and astonishment.[59]}

[Lynn Rotanno]

Tesla also explained the principles of the rotating magnetic field and induction motor by demonstrating how to make an egg made of copper stand on end in his demonstration of the device he constructed known as the "Egg of Columbus".

Also in the late 1880s, Tesla and Edison became adversaries in part due to Edison's promotion of direct current (DC) for electric power distribution over the more efficient alternating current advocated by Tesla and Westinghouse. Until Tesla invented the induction motor, AC's advantages for long distance high voltage transmission were counterbalanced by the inability to operate motors on AC. As a result of the "War of Currents," Edison and Westinghouse went nearly bankrupt, so in 1897, Tesla released Westinghouse from contract, providing Westinghouse a break from Tesla's patent royalties. Also in 1897, Tesla researched radiation which led to setting up the basic formulation of cosmic rays.[60]

[Lynn Rotanno]

When Tesla was forty-one years old, he filed the first basic radio patent (U.S. Patent 645,576). A year later, he demonstrated a radio-controlled boat to the US military, believing that the military would want things such as radio-controlled torpedoes. Tesla had developed the "Art of Telautomatics", a form of robotics, as well as the technology of remote control.[61] 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. Tesla called his boat a "teleautomaton" and said of it, "You see there the first of a race of robots, mechanical men which will do the laborious work of the human race."[62] Radio remote control remained a novelty until the 1960s. In the same year, Tesla devised an "electric igniter" or spark plug for Internal combustion gasoline engines. He gained U.S. Patent 609,250, "Electrical Igniter for Gas Engines", on this mechanical ignition system. Tesla lived in the former Gerlach Hotel, renamed The Radio Wave building, at 49 W 27th St. (between Broadway and Sixth Avenue), Lower Manhattan, before the end of the century where he conducted the radio wave experiments. A commemorative plaque was placed on the building in 1977 to honor his work.

[Lynn Rotanno]

Wireless transmission of power and energy demonstration during his high frequency and potential lecture of 1891.

[Lynn Rotanno]

Nikola Tesla's AC dynamo used to generate AC which is used to transport electricity across great distances. It is contained in U.S. Patent 390,721.

[Lynn Rotanno]

Electromechanical devices and principles developed by Nikola Tesla:

    * Various devices that use rotating magnetic fields (1882)
    * The Induction motor, rotary transformers, and "high" frequency alternators
    * The Tesla coil,[32] his magnifying transmitter, and other means for increasing the intensity of electrical oscillations (including condenser discharge transformations and the Tesla oscillators[33][34])
    * Alternating current long-distance electrical transmission system[35] (1888) and other methods and devices for power transmission
    * Systems for wireless communication (prior art for the invention of radio) and radio frequency oscillators[36]
    * Robotics and the "AND" logic gate[37]
    * Electrotherapy Tesla currents[38][39][40]
    * Wireless transfer of electricity and the Tesla effect[41][42]
    * Tesla impedance phenonomena[43]
    * Tesla electro-static field
    * Tesla principle
    * Bifilar coil
    * Telegeodynamics
    * Tesla insulation
    * Tesla impulses[44]
    * Tesla frequencies[32]
    * Tesla discharge[32]
    * Forms of commutators and methods of regulating third brushes
    * Tesla turbines (eg., bladeless turbines) for water, steam and gas and the Tesla pumps
    * Tesla igniter
    * Corona discharge ozone generator
    * Tesla compressor
    * X-rays Tubes using the Bremsstrahlung process
    * Devices for ionized gases and "Hot Saint Elmo's Fire".[45]
    * Devices for high field emission
    * Devices for charged particle beams
    * Phantom streaming devices[46]
    * Arc light systems
    * Methods for providing extremely low level of resistance to the passage of electrical current (predecessor to superconductivity)
    * Voltage multiplication circuitry
    * Devices for high voltage discharges
    * Devices for lightning protection
    * VTOL aircraft
    * Dynamic theory of gravity
    * Concepts for electric vehicles
    * Polyphase systems

[Lynn Rotanno]

Colorado Springs

In 1899, Tesla decided to move and began research in Colorado Springs, Colorado, where he would have room for his high-voltage, high-frequency experiments. Upon his arrival he told reporters that he was conducting wireless telegraphy experiments transmitting signals from Pikes Peak to Paris. Tesla's diary contains explanations of his experiments concerning the ionosphere and the ground's telluric currents via transverse waves and longitudinal waves.[63] 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).[64] Tesla also investigated atmospheric electricity, observing lightning signals via his receivers. Reproductions of Tesla's receivers and coherer circuits show an unpredicted level of complexity (e.g., distributed high-Q helical resonators, radio frequency feedback, crude heterodyne effects, and regeneration techniques).[65] Tesla stated that he observed stationary waves during this time.[66]

[Lynn Rotanno]

Tesla researched ways to transmit power and energy wirelessly over long distances (via transverse waves, to a lesser extent, and, more readily, longitudinal waves). He transmitted extremely low frequencies through the ground as well as between the Earth's surface and the Kennelly-Heaviside layer. He received patents on wireless transceivers that developed standing waves by this method. In his experiments, he made mathematical calculations and computations based on his experiments and discovered that the resonant frequency of the Earth was approximately 8 Hertz (Hz). In the 1950s, researchers confirmed that the resonant frequency of the Earth's ionospheric cavity was in this range (later named the Schumann resonance).