>>> Tesla Q&A — Table of Contents

My 12kv/90ma coil is nearing completion and I was thinking that I could do some sort of experiment with wireless power transmission. . . . I recall someone talking about rigging up another coil to attach to a light bulb which could be lit up from a fairly significant distance.  I've researched this a bit but I can't really find anything about a receiving coil and light bulbs.  Any information would be greatly appreciated.

I'm looking for information about some experiments Tesla conducted in Canada.  Any information would be a great help!

I understand that Tesla proposed a wireless transmission system that required the construction of a 15-mile high antenna.  What could he have been thinking?

Would you help me with a translation of the words that led Tesla to conceive the induction motor?

My 12kv/90ma coil is nearing completion and I was thinking that I could do some sort of experiment with wireless power transmission. . . . I recall someone talking about rigging up another coil to attach to a light bulb which could be lit up from a fairly significant distance. I've researched this a bit but I can't really find anything about a receiving coil and light bulbs, so if anyone has info it would be greatly appreciated.

When I was on the Board of Directors of the International Tesla Society in 1990 I did improvised a damped-wave Tesla coil RF transmitter.  It was based upon a fellow board member's tabletop TC display unit.  The approximately 1" knob topload was replaced with a copper flush-valve float, and moved off of the secondary on to an improvised insulated stand a few inches higher than its original position and a little bit off to the side.  I modified its glass-plate capacitor by adding another sheet of aluminum foil.  The receiving transformer, prepared beforehand, had an AWG 30 gauge primary wound on a 1.75" cardboard tube.  The secondary to which the load was connected was wound on top of the helical-resonator primary towards the lower end of the single-layer coil in exactly the same fashion as Tesla did when he was in Colorado Springs in 1899.  The load consisted of a 6-volt pilot light.  The elevated terminal was a sheet of aluminum foil hung off of another improvised stand made of wooden sticks.  The lamp was brightly lit at a range of about 15 feet.  It's not at all hard to do.

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I'm looking for information about some experiments that Nikola Tesla conducted in the Province of Quebec, Canada.  Somebody told me that Tesla had been living in Quebec city during a certain period, and he made some works in the Saguenay-Lac-Saint-Jean area.  Any information would be a great help!

According to Arthur Mathews, Tesla demonstrated the wireless transmission of electrical energy around the early 1930s.  The transmitter was assembled in the early Spring at a large camp in the woods near Lake Edwards, about 10 miles from Sanford, Quebec, Canada.

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I understand that Nikola Tesla proposed a wireless transmission system that used electrical conduction instead of radio waves.  This method was put forth in his U.S. Patents No. 645,576 and 649,621 where he mentions a 15-mile high antenna wire.  It seems to me that the obstacles to building such an elevated structure would be insurmountable.  What could he have been thinking?

The reference to, "maintaining terminals at elevations of fifteen miles or more above the level of the sea" is followed by the following self-explanatory statement.

Through my discoveries before mentioned and the production of adequate means, the necessity of maintaining terminals at such inaccessible altitudes is obviated . . .  

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Would you be so kind to help me with the translation of these inspiring words that let Tesla to conceive his motor?

One afternoon, which is ever present in my recollection, I was enjoying a walk with my friend in the City Park and reciting poetry.  At that age I knew entire books by heart, word for word.  One of these was Goethe's "Faust." The sun was just setting and reminded me of the glorious passage:

"Sie ruckt und weicht, der Tag ist uberlebt, 
Dort eilt sie hin und fordert neues Leben.
Oh, dass kein Flugel mich vom Boden hebt
Ihr nach und immer nach zu streben!

Ein schoner Traum indessen sie entweicht,
Ach, zu des Geistes Flugeln wird so leicht
Kein korperlicher Flugel sich gesellen!"

These lines are from Chapter 3 of Tesla's autobiography My Inventions.  Translated into English they read as follows:

The glow retreats, done is the day of toil; 
It yonder hastes, new fields of life exploring;
Ah, that no wing can lift me from the soil
Upon its track to follow, follow soaring!

A glorious dream! though now the glories fade.
Alas! the wings that lift the mind no aid
Of wings to lift the body can bequeath me. 

Hi, my name is Lewis and I have to do a report on inventors.  I chose Nikola Tesla.  Can you give me the list of languages he spoke?

In addition to his native language Serbo-Croatian, Tesla also spoke Latin, Italian, French, German, and English.  (See Nikola Tesla  The European Years, by D. Mrkich.)  [clip]

Differing figures are cited for the total number of patents obtained by Tesla worldwide.   What is the actual number?

Using data found in the CATALOGUE OF TESLA PATENTS, Belgrade, 1987, and other sources [1,2,3], it is apparent there were at least 236 patents issued to Tesla in 25 countries over the course of his lifetime. . . . Judging from the available data, the actual figure probably lies somewhere around  325 Tesla patents worldwide.  Full answer

Are there any pictures of Tesla's rotating coherer?  Also, what would allow electricity to be transmitted thru the earth to great distances?

The best image I know of is the drawing on page 99 of the Colorado Springs Notes, a copy of Tesla's original drawing.

About Tesla's claim for transmission by earth currents with only minimal losses, he made a point of describing the process as being much the same as sending electricity through a wire.  In his system the physical conductor is the earth itself.  Compared with, say, copper wire, one might not think that dirt, rock, etc. would make a very good electrical conductor.  Actually, the Earth's vastly greater cross-sectional area provides a remarkably low resistance path for the flow of earth currents. . . .  Full answer

Why did Tesla make his coil in the first place?  Do they have any practical purposes?

Tesla built his first oscillator as a tool for studying high-frequency electrical phenomena.  Practical applications for this type of electrical power supply include a form of high-efficiency, high-frequency lighting ballast.  It can be used to power fluorescent and incandescent lamps, as well as high-frequency arc lamps.  The carbon button incandescent lamp can be lit with only one connecting wire.  He also developed a single-wire electric motor.

His work with the single terminal incandescent lamp led him to investigate the generation and physical properties of X rays.  Tesla's more advanced tubes differ from typical X-ray tubes in that they have no target electrode and produce X rays through vacuum high-field emission and a process known as Bremsstrahlung.

Tesla's oscillator can be used to power a device for the production of ozone and to induce a reaction between oxygen and relatively inert nitrogen, producing gaseous nitrogen oxides.  It can also be used as a wireless transmitter, being able to produce radio waves thousands of times more powerful than the simple spark-coil transmitter used by Heinrich Hertz.    Full answer

On a wire-size table, why does the wire gauge number decrease as the diameter increases?

In general a wire size gauge number corresponds to the number of operations involved in drawing a wire, a larger figure representing more operations resulting in a smaller diameter.  Full answer

I've been working on a business venture that requires the use of a gasoline powered water pump.  A colleague mentioned the "Tesla bladeless disk turbine" as an efficient and cost effective solution to my pumping problem.  I was wondering if you know of anyone that sells these pumps?

The only company that I know of which manufactures and sells Tesla disk pumps is the Discflo Corporation. Here's their contact information:

Discflo Corporation
1817 John Towers Ave
El Cajon, CA 92020, USA. 
Phone: (619) 596 3181
Toll-free: 1-800-DISCFLO
Fax: (619) 449 1990
discflo@cts.com

Looking for a Tesla turbine? The first company I'd contact is EPI:

Electric Power International / Entrivac
1421 Hemlock St.
Louisville, KY 40211
(502) 772-1633, (502) 772-9711
Tesla turbine manufacturer

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What are the most important books to read in order to learn about Tesla's work?

• My Inventions : The Autobiography of Nikola Tesla, Nikola Tesla; Ben Johnston, Editor

• The Problem of Increasing Human Energy, Nikola Tesla

• Inventions, Researches and Writings of Nikola Tesla, Nikola Tesla; Thomas Commerford Martin, Editor

• The Transmission of Electric Energy Without Wires Nikola Tesla

• Nikola Tesla On His Work With Alternating Currents and Their Application to Wireless Telegraphy, Telephony, and Transmission of Power, Tesla Presents Series Part 1, Leland I. Anderson, Editor

• Nikola Tesla: Lecture Before The New York Academy of Sciences, April 6, 1897, Tesla Presents Series Part 2
  Leland I. Anderson, Editor

• High Frequency Oscillators for Electro-therapeutic and Other Purposes, Nikola Tesla

• Nikola Tesla: Guided Weapons & Computer Technology, Tesla Presents Series Part 3, Leland I. Anderson, Editor

• Nikola Tesla's Teleforce & Telegeodynamics Proposals , Tesla Presents Series Part 4, Leland I. Anderson, Editor

• Nikola Tesla — Lectures — Patents — Articles, Nikola Tesla

• Nikola Tesla — Colorado Springs Notes, 1899-1900, Nikola Tesla; Commentary by Aleksandar Marincic

• Dr. Nikola Tesla — Complete Patents, Nikola Tesla; Compiled by John T. Ratzlaff

• Dr. Nikola Tesla — Selected Patent Wrappers, Nikola Tesla; Compiled by John T. Ratzlaff

• Tesla Said, Nikola Tesla; Compiled by John T. Ratzlaff

• Solutions to Tesla's Secrets, Nikola Tesla; Compiled by John T. Ratzlaff; Thomas Bearden

• Nikola Tesla -- Collected Articles and Lectures, Volume 1, Nikola Tesla; Compiled by Franz Ferzak & Ulrich Heerd

• Nikola Tesla -- Collected Articles and Lectures, Volume 2, Nikola Tesla; Compiled by Franz Ferzak & Ulrich Heerd

• Nikola Tesla — Correspondence with Relatives, Nikola Tesla; Translated by Nicholas Kosanovich

• Prodigal Genius : The Life of Nikola Tesla, John J. O'Neill, 1944

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What year would you consider as being the Wardenclyffe Centennial?

With completion of the basic tower 1903 became a landmark year for Tesla's Long Island Plant, although it was not yet functional due a fatal design flaw.  It cannot be considered as having reaching its fully developed state until around 1907 or later.  Full answer

Did Tesla really invent the loudspeaker?

While I've seen nothing to indicate that Tesla invented the modern-day loudspeaker as we know it, the book Prodigal Genius by John J. O'Neill contains two passages that might lead one to believe otherwise. . . . In 1916 Tesla indeed described a true audio transducer that was part of a wireless receiver.  Full answer

Can you explain, within accepted laws of physics, what was Tesla trying to accomplish at Colorado Springs and on Long Island?

This appeared in the Electrical Review - N. Y., Nov, 30, 1898, pp. 344, 345, "TESLA DESCRIBES HIS EFFORTS IN VARIOUS FIELDS OF WORK"

     ". . . Starting from two facts that the earth was a conductor insulated in space, and that a body cannot be charged without causing an equivalent displacement of electricity in the earth, I undertook to construct a machine suited for creating as large a displacement as possible of the earth—s electricity. . . ."  Full answer

What is the difference between present day low-frequency wireless transmitters and Tesla's system?

It is proposed that fundamentally identical electrical oscillators consisting of an RF current source, an elevated conductor and a robust ground connection can be configured in ways which are conducive to the production of two different types of surface wave.  It is proposed that low frequency wireless communications can be accomplished by the production of either electromagnetic radiation in the form of space wave induced ground currents and an accompanying electromagnetic wave, or the generation of a pulsed magnetic field and production of ground currents at the transmitter resulting in an accompanying, poorly defined trapped surface-wave (see Zenneck surface wave).  Full answer

Did Marconi really receive a radio signal from across the Atlantic in 1901?  I understand there were literally dozens of other people "on the air" at the time of his trans-Atlantic wireless experiments and the Morse code "S" could have come from a relatively nearby transmitter.

Yes, I have also heard that a number of stations were on the air at the same time as Marconi's experiments. It has been pointed out the actual propagation of a signal over a distance of 2100 miles was very unlikely at the general frequency that was being used.  The validity of Marconi's claim of having detecting trans-Atlantic signals from Poldhu, Cornwall is brought into doubt by the presence of these other RF emissions, some certainly closer to his Newfoundland receiving site.

I read a 1917 story, "U. S. Blows Up Tesla Radio Tower," about the destruction of Wardenclyffe which suggests that Tesla said he had no interest in wireless communications, and that he only wanted to transmit power for electric lights and motors.  If what he said was true, he rather shot himself in the foot.

While it is true that Tesla intended to use the Long Island facility to perform experiments, "with the transmission of electrical energy for power and lighting purposes by wireless. . . ."  he repeatedly made it clear the plant's primary function was global wireless telecommunications and broadcasting.  Full answer

I was wondering if you are familiar with the 'teslar' watch?  The company who makes it added an 'r' to the name, however refers to an invention by Nikola Tesla that was added to the watch.

I have heard of the "teslar watch," but don't know very much about it.  Apparently it contains an oscillator with a mobius loop coil which emits a low-power ELF signal which is purported to protect the wearer from the possible detrimental effects of other ELF signals that might be present in the environment.  There is a paper by Andrija Puharich in the Proceedings of the 1984 Tesla Centennial Symposium titled "Method and Means of Shielding a Person from the Polluting Effects of ELF Waves and All Other Environmental Electromagnetic Emissions" which addresses this subject.  Full answer

I'm looking for books with information about bifilar-wound coils.  Could you please give me some names?

I have two books which refer to bifilar-wound coils.  The first is Dr. Nikola Tesla Complete Patents which contains the U.S. Patent No. 512,340, COIL FOR ELECTRO-MAGNETS, described in the following claims:

1. A coil for electric apparatus the adjacent convolutions of which form parts of the circuit between which there exists a potential difference sufficient to secure in the coil a capacity capable of neutralizing its self-induction.

2. A coil composed of contiguous or adjacent insulated conductors electrically connected in series and having a potential difference of such value as to give the coil as a whole, a capacity sufficient to neutralize its self-induction as set forth.

The second book is Proceedings of the 1990 International Tesla Symposium which contains a paper by Moray B. King, "Tapping the Zero-Point Energy and Scalar Current."  The paper refers to four types of bifilar-wound coil, parallel-wound, series connected (as described above), parallel-wound, parallel connected, and the counter-wound caduceus coil, both series and parallel connected.  Also, King's paper "Demonstrating a Zero-Point Coherence" in the Proceedings of the 1988 International Tesla Symposium proposes an experiment involving the pulsed excitation of a caduceus coil surrounding a plasma tube in ion-acoustic resonance.  Full answer

I've heard stories about the Tesla turbine that cite a figure of 95% efficiency, and have been unsuccessful in obtaining any information regarding this claim.  I was wondering if you could help in some way.  In addition, why haven't these devices been utilized in the mainstream.  Its hard to believe that it wouldn't have peeked its head out somewhere in the commercial realm.

I'm fairly certain the 95% figure you heard about can be traced back to a paper written by a Prof. Warren Rice, titled "Tesla Turbomachinery," and published in the Conference Proceedings of the IV International Tesla Symposium, September 22-25, 1991, Serbian Academy of Sciences and Arts, Belgrade, Yugoslavia.  Prof. Rice states that bulk-parameter analysis has been used to accurately model laminar flow in multiple disk rotors, asserting that "...calculated results for laminar flows are in excellent agreement with experimental results for such flows. . . . With proper use of the analytical results, the rotor efficiency using laminar flow can be very high, even above 95%. . . ."  Keep in mind that while the rotor efficiencies can be very high, the fluid flow losses entering and exiting the rotor can be significant and difficult to reduce.  Full answer

Hello!  I'm interested in the theory behind how the Wardenclyffe tower would have operated.  The transmission of power through a distance, through thin air is a mystery to me—not to mention being able to direct the energy flow to specific points on the globe!   Were there smaller projects or demonstrations which demonstrated this effect?  How do you defeat the "loss of power over a distance" phenomena?  If this thing works, it just seems "dumb" not to develop it. (Pardon my attitude).  Clue me in!!

For starters, the transmission medium is the earth itself with propagation being by conduction. And, it appears there would be a gliding surface wave involved—the Zenneck Surface Wave. Tesla wrote that the earth itself comprised a giant LC circuit that could be electrically resonated at certain frequencies, and that his transmitter would be capable of exciting this system.  The Colorado Springs experiments were said to have confirmed this hypothesis.  Because the radiated power was intentionally suppressed, the loss of power as a function of distance was not a real issue.  Full answer

I remember reading an old Popular Mechanics magazine article, that discussed bladeless turbines.  It mentioned such things as better jet engines and stated the design was based on a Tesla patent.  Is there any truth to this?

In the September 1965 Popular Mechanics article "Make a Model Tesla Turbine" Walter Burton wrote, "One of the great 'lost' engines, Tesla's long-neglected turbine, is due for a revival."  The Tesla bladeless turbine consists simply of multiple shaft mounted disks suspended upon bearings which position the rotor system within its cylindrical casing.  In operation high velocity gases enter tangentially at the periphery of the disks, and flow through the narrow spaces between them in free spiral paths to exit, depleted of energy, through central exhaust ports.  The slight viscosity of the moving gas along with its molecular adhesion to the disks combine to drag them along, efficiently transferring the fuel's energy to the disks and on to the shaft.  There are some who believe that if this engine was built using advanced technology and materials it would have a power-to-weight ratio that compares favorably with bladed turbine engines.  The U.S. Patents which covered the pump and the engine were issued in 1913 under the titles "Fluid Propulsion" and "Turbine" [Dr. Nikola Tesla—Complete Patents].  Another related patent that describes a gas burning version of the disk turbine was issued in 1920 under the title "Valvular Conduit."

Where can I find further documentation about the bladeless turbine?

Tesla obtained a number of turbomachinery-related patents in the United States and abroad which serve as primary sources of information on these devices.  They are included in the Nikola Tesla Patent Collection — On CD-ROM
Nikola Tesla, Compiled by Bruce A. Perreault.  You may also wish to look into the Phoenix Turbine Builders Club and The Tesla Engine Builders Association websites.  Full answer

Just curious as to what frequency Tesla used to send his electricity from Niagara Falls. We have a small wager going that it was less than 60 Hz.

At the start of 1897 there were some 300 electrical power generating plants operating here in the United States. The most important of these belonged to the Niagara Falls Power Company who had transmitted 1000 horse power to Buffalo, New York on November 16, 1896. The original AC power plant, dubbed the Edward Dean Adams Hydro-Electric Power Station Number One, was designed to operate at a frequency of 25 cycles per second (Hz). The current was used for the propulsion of electric street cars. A subsequent expansion of the Niagara Falls facility included a conversion to the now familiar 60 Hz.

Did Tesla invent the fluorescent light?

While Tesla experimented with what he called "phosphorescent" lamps, it was French physicist Alexandre-Edmond Becquerel (1820-1891) who first conceived the idea of placing a fluorescent coating on the inner surface of a high voltage gas discharge tube.  Full answer

I am currently building a Tesla coil. Any suggestions where to source primary power supply transformers?

Visit a local neon sign shop for your power supply transformer. The electric utility company that services your area might also be able to provide you with a high tension transformer or at least point you in the right direction to obtain one.  Full answer

Have you ever been to Griffith Observatory in L.A., California?  We have a Tesla Coil that we obtained in 1935 from a carnival.  We demonstrate the T-Coil by having patrons hold a fluorescent tube (which lights up).  We also demonstrate an "electric kiss" by having couples make a small gap between their lips as one of the partners touch a nail near the T-Coil (A tiny spark jumps from lip to lip).  There are a few other things we do, and I'm always trying to come up with something new.  Do you have any suggestions?  Thank you!

I haven't been to the Griffith Observatory but understand from an associate in Burbank that your Tesla coil is an impressive one. As for novel demonstrations, while there are a number that have been mentioned in the literature most of them involve direct connection to the oscillator. . . . With an oscillator such as yours, it might be best to focus on those demonstrations that can be performed without direct physical contact. While the lighting of a fluorescent tube is a tried and true standard, it is possible to greatly improve the performance of this demonstration by adding a tuned circuit that is adjusted to vibrate in harmony with transmitter. . . .  Full answer

I read that Tesla once demonstrated a small remote control boat in New York at the turn of the century.  Is this true and how did he make a remote control boat work prior to the invention of radio?

The small radio-controlled boat that you read about was first demonstrated to the public in 1898 at New York City's old Madison Square Garden.  Tesla first demonstration of an apparatus for radio transmission and reception took place in 1893 during a presentation in St. Louis before the National Electric Light Association.  Full answer

Please tell me about Tesla's invention of the AND logic gate.

Tesla's work on the development of an independent remotely-controlled device—the "telautomaton" resulted in two U.S. patents, "System of Signaling" and "Method of Signaling" describing the AND-gate circuit.  After World War II when computer hardware manufacturers attempted to patent digital logic gates in general, the U.S. Patent Office asserted Tesla's turn-of-the-century priority in their electrical implementation.  Full answer

I just read online that the telautomaton which Tesla demonstrated at the old Madison Square Garden used a voice recognition system that allowed it to respond to his verbal commands.  Is this really true?

This online account is a perfect example of the grossly distorted history that occasionally arises regarding Nikola Tesla. In truth, the boat's functions were controlled by changing the position of a rotary switch mounted on a box which contained the system's radio-control transmitter.  (See figure 9, "Method of and Apparatus for Controlling Mechanism of Moving Vessels or Vehicles"

Could you briefly summarize Tesla's invention of radio and the Supreme Court case of Tesla vs. Marconi? Marconi is mistakenly identified in every history book as the inventor of Radio. Thanks.

Nikola Tesla's contribution to the invention of radio involved reworking the primitive transmitters and tuned receiving circuits which his predecessors had developed.  Between 1898 and 1903 Tesla was granted 10 U.S. patents covering his work in these areas.  In 1904 Marconi was able to get his own patent using some of Tesla's ideas.  The issue of patent infringement by Marconi was addressed in a lawsuit brought by Tesla 1915.  Nothing significant resulted from this until 1916 when the Marconi Wireless Telegraph Company of America itself sued the United States for alleged damages resulting from the use of wireless during WWI.  In 1935 a ruling of the United States Court of Claims essentially invalidated the fundamental Marconi patent.  The U.S. Supreme Court affirmed this ruling on June 21, 1943.  Full answer

Who improved the early spark-gap transmitter design allowing much higher levels of radio-frequency power output?

Some historians credit Reginald Fessenden in 1900 for making improvements to the earliest spark-gap transmitters allowing significantly higher levels of radio-frequency energy to be concentrated into a damped or partially damped wave of a single frequency.  Other scholars say it was Ferdinand Braun performed in a hastily improvised demonstration in September 1898.  In reality, Nikola Tesla revealed the basic techniques for improving transmitter performance with a series of U.S. patents, starting with his "System of Electric Lighting" Patent No. 454,622, dated June 23, 1891.  Full answer

An article in the May 1919 issue of the Electrical Experimenter, "The True Wireless," talks about a "rotating brush wireless detector" that Tesla used, and in the January 1919 issue there is a photo of a device identified as "Tesla's Static Eliminator."  Do you have any knowledge of these devices?

The "rotating brush wireless detector" was one of a broad array of experimental single terminal vacuum tubes designed to be operated in conjunction with one of Tesla's high-voltage power supplies. The construction of the tube itself was very similar to the now popular "plasma globe" novelty item.  Regarding Tesla's static eliminator, as you have discovered, there is relatively little info available about this dinner-plate size device. It was a variable coupling RF transformer consisting of two flat spiral or pancake coils.  Full answer

I remember reading somewhere that Tesla had successfully transmitted power through the earth.  Can you fill me in on the details of this astonishing achievement?

Tesla's first efforts towards this end started in 1891 and were intended to simply "disturb the electrical equilibrium in the nearby portions of the earth... to bring into operation in any way some instrument."  In other words the object of his initial experiments was simply to produce effects locally and detect them at a distance.  It was at this Colorado "Experimental Station" in 1899 that Tesla had some early success in wireless power transmission.  In one of his demonstrations, photographs show that "a small incandescent lamp was lighted by means of a resonant circuit grounded on one end, all the energy being drawn through the earth" from the nearby transmitter.  In 1907, after tests conducted at the Wardenclyffe plant he said, ". . .the little lamp will spring into the same brilliancy anywhere on the globe, there being no appreciable diminution of the effect with the increase of distance from the transmitter."  Full answer

I heard that part of Tesla's transmitter is still in a pit near the Wardenclyffe building and that it was designed so it could be raised or lowered for tuning.  Is this true?

The "pit" that you heard about is probably a reference to the 120 foot deep well-like shaft that was positioned directly below the immense wooden tower which can be seen in many old photographs of the Wardenclyffe site. It was excavated so that a series of iron pipes could be installed deep underground to serve as a connection between the oscillator and the earth.  After Tesla lost the property, practically everything of value was stripped from the site for salvage.  In light of this fact it is unlikely that any equipment remains in the now back-filled shaft.  Recent bore-hole surveys reaching all the way down to the 120 foot level tend to support this conclusion.  Full answer

Wasn't Tesla researching the broadcast of power in his last project?

There is some circumstantial evidence, primarily in the form of newspaper articles, indicating that large-scale wireless power transmission experiments were planned in the mid 30s time frame.  For example, an article appeared in The New York Daily News, April 2, 1934 titled "Tesla's Wireless Power Dream Nears Reality" which mentions a planned test run of a "motor car" using wireless transmission of energy to power the automobile.  Full answer

I've read a lot on the internet about Tesla and a 1931 Pierce Arrow.  Apparently, he installed an 80 hp electric engine and drove the car for a week on radiant energy at speeds up to 90mph.  The information was relayed by his nephew, Peter Savo, to a Derek Ahlers after Tesla's death.  What's your take on this story? 

It would appear the radiant energy Pierce Arrow story is a fabrication—mainly because Tesla didn't have a nephew named Peter Savo.  On the other hand, Tesla believed that his system for the wireless transmission of electrical energy could be used for the propulsion of aircraft and automobiles.  An article that appeared in the New York Daily News, April 2, 1934 titled "Tesla's Wireless Power Dream Nears Reality" mentions the planned test run of a "motor car" using wireless transmission of electrical energy to power the vehicle.

Could you write something about Tesla's experiments with electric cars?

Tesla's involvement in this area is best addressed in general terms. While there is no corroborated evidence that Tesla ever built an electric automobile, he is known to have encouraged others to pursue the idea of electric propulsion.  He defined this as the use of an engine to generate electricity which was transmitted to an electric motor used to turn a wheel or propeller, instead of turning them by direct mechanical means. If this sounds familiar you're right, as the idea has recently seen a revival by the automobile industry and others under the name "hybrid electric drive."  Full answer

I've heard that at some point in Tesla's life he came up with a now-unknown energy source. I would like to know if you have any information (background, possible energy source, etc.) that you could relate. I've always found subjects such as this interesting.

Among his various pursuits Nikola Tesla had a lifelong involvement with the identification and harnessing of energy sources. His early dream of deriving electrical power from waterfalls and the vision's subsequent fulfillment at Niagara Falls and elsewhere is a classic example of this. In addition to falling water, he also recognized the energy potential of the wind, the sun and, perhaps most importantly, terrestrial heat—what is now referred to as geothermal energy.  As his experience grew he became convinced that it should also be possible to obtain energy directly from the ambient medium.  Full answer

I grew up in Colorado Springs, and remember hearing all sorts of stories about Tesla.  One rumor I heard involved Tesla and some sort of weather control device. Have you heard this story, or found any substantiation?

As you probably know, in 1899 Nikola Tesla spent some time in Colorado Springs. He was there to work out various design details for the wireless communications facility that he would later build on the North Shore of Long Island, New York. In 1917 during a speech before the American Institute of Electrical Engineers Tesla said that while in Colorado his large oscillator once created a dense cloud of water vapor inside of the laboratory structure. He also speculated that properly designed plants might be installed in arid regions to draw in water for irrigation. The story that you heard is probably related to this incident. By the way, the entire speech is reprinted in the book Tesla Said. (See page 188 for the specific account.) [clip]

I read that Tesla could have had something to do with the explosion in Tunguska area in Russia — that he was supposedly trying to get the attention of a explorer that was near the region at the time.  Something about a tower and sending a ball of current through the air, then it exploded over Tunguska.  Could you explain what that might be about?

Recent speculations about Tesla's involvement in the 1908 Tunguska event were initially fueled by a few statements made some time ago in the New York Times. In the first of these, published in March 1907 he speaks of "projecting wave-energy" and again in April 1908 reference was made to the "direct application of electrical waves without the use of aerial engines or other implements of destruction."  In 1915 he stated,

"It is perfectly practicable to transmit electrical energy without wires and produce destructive effects at a distance. I have already constructed a wireless transmitter which makes this possible, and have described it in my technical publications, among which I may refer to my patent 1,119,732 recently granted."

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In the book, Tesla — Man Out of Time, the author wrote about a "death ray" that Tesla had reportedly invented.  Could you tell me what exactly the Death Ray was, and how it worked?

I was told that Tesla was able to remotely boil a 50 gal drum of oil from 100 miles away ... how did he do this ?

Many stories have been told of feats that Tesla is said to have performed which have no readily apparent basis in fact, and this could very well be one of them.  On the other hand, the transmission of energy to achieve such a result might be accomplished with Tesla's particle-beam device—assuming the fundamental concept is a valid one.  Considering statements made in a 1934 letter to the Westinghouse Electric & Manufacturing Co., Tesla certainly did. [clip]

Is it true that Edison used some of Tesla's inventions as his own?

In 1884, literally within weeks of his arrival in New York City from Europe, Tesla went to work for Thomas Edison. One of his early assignments was the redesign of some machinery related to Edison's direct current power distribution system. Tesla's own words might best describe what happened next. "... I designed twenty-four different types of standard machines with short cores and of uniform pattern which replaced the old ones. The Manager had promised me fifty thousand dollars on the completion of this task but it turned out to be a practical joke. This gave me a painful shock and I resigned my position." You can read the complete account in Tesla's autobiography My Inventions.  [clip]

Did Tesla ever reside in New Jersey and if so, what did he focus on there?

While nothing could be found to indicate that Tesla had a residence in New Jersey, his first business venture, the Tesla Electric Light Company, was headquartered there in Rahway. It was formed in 1884 to satisfy a substantial market for electric-arc lights used to illuminate streets and factories. It is worthwhile noting that Tesla's first U.S. patent application dated March 30, 1885 was for an electric-arc lamp. [clip]

Who was Tesla's best friend? (I'm tempted to ask the corollary questions: "Did Tesla have a dog? If so, what was his name?")

I would have to say that Tesla's best friend was Robert Underwood Johnson, editor of the Century Magazine and personal confidant. This is evident from the large volume of Johnson correspondence that has been preserved at the Nikola Tesla Museum in Belgrade. Tesla also developed a strong relationship with Samuel Clemens, although not very many letters were written between the two. An excellent source of information about Tesla's interpersonal relationships is the recent Tesla biography Wizard — The Life and Times of Nikola Tesla.

As for Tesla's other "best friend," in his youth it was a cat named Macak. This animal is the subject of a charming short story related to a Miss Pola Fotitch in 1939. It can be found on page 283 of the book Tesla Said which contains many significant accounts in Nikola Tesla's own words. [clip]

I've heard of Tesla having some type of mysterious pet fireball that he would randomly present at will. Is there anything published about this?

The "fireball" account that you heard about can be traced back to the article "The New Wizard of the West" which appeared in the May 1899 issue of Pearson's Magazine, London. Part of this article can be found on pages 3-4 of the Tesla biography titled Tesla — Man Out of Time. Tesla himself discussed the production of fireballs or ball lightning in his Colorado Springs Notes written at the time of his 1899 wireless propagation experiments.  See also Ball Lightning & Tesla's Electric Fireballs.  [clip]

Was Tesla suffering from some form of autism?

Given his great capacity for original thought and ability to mentally visualize mechanisms in extreme detail, it's likely that Tesla was autistic.  His solitary life style and single mindedness towards an engagement in the creative act lend support to this conclusion.  Visit " Autism & The Internet" or "It's The Wiring, Stupid" by Harvey Blume and Talk of the Nation, Strange Scientists for additional thoughts on this subject.  [Answer revised on 10/06/2004.  My thanks to those who provided their valuable input about this state of mind.] [clip]

What was Tesla's IQ? Was it ever measured?

I have asked around and no one contacted has knowledge of Tesla ever having been tested for IQ. There is anecdotal evidence that even as a youth Tesla had a proclivity for problem solving, so, considering his lifetime achievements, I think it is fair to say that he was a truly gifted individual.  [clip]

Was Tesla Serbian? I was under impression that he was Slovenian.

Nikola Tesla was born in Croatia of Serbian heritage. He is known to have said, "I am equally proud of my Serbian birth and Croation Fatherland."  [clip]

I had read that upon Tesla's death that the U.S. government stormed his residence and lab seizing all of his note's and papers. This being done without a proper warrant. Is this true to your knowledge? and if so has anything been done to recover the property?

From all accounts, the actions taken following Dr. Tesla's death on January 7, 1943 were conducted in an orderly and respectful fashion. According to those present at the time, Tesla's papers and other personal possessions were placed under the charge of the Office of Alien Property which issued a certificate of ownership to his nephew Sava Kosanovich.  It being wartime and considering Tesla's involvement in remote detection and advanced weapons development, it is believed the materials were thoroughly inspected for items that might have been important to national defense.  The estate was consolidated at a Manhattan storage facility and in 1952 it was shipped off to Yugoslavia.  See Tesla—Man Out of Time, pp. 258-280, and Wizard—The Life and Times of Nikola Tesla, pp. 436-462 to learn more about the circumstances surrounding Tesla's death and the handling of his estate.  [clip]

SELECTED TESLA WRITINGS