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I've heard stories about the tesla turbine that cite a figure of 95% efficiency.  Do you have any information regarding this claim? And, why haven't these devices been utilized in the mainstream?

What is the theory behind how the Wardenclyffe tower would have operated?

An old Popular Mechanics article that discussed bladeless turbines mentioned such things as better jet engines based on a Tesla patent. Is there any truth to this?

Where can I find further documentation about the bladeless turbine?

What frequency did Tesla use to send electricity from Niagara Falls?

Did Tesla invent the fluorescent light?

Any suggestions where to source primary power supply transformers for Tesla Coils?

Griffith Observatory in L.A. asks about any new or different high-voltage demonstrations they can use with their Tesla coil.

Is it true that Tesla once demonstrated a remote control boat?  If so, how did it work?

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

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.  And, according to Prof. Rice, "There is little or no literature devoted to the flows that cause the main losses in Tesla-type turbomachinery."

As for why the disk-turbine design hasn't seen significant practical application, this is a complex issue.  According to the Tesla Engine Builders Association, mainstream application of the basic technology has already been achieved in the industrial pumping arena.  Perhaps practical application of the gas turbine is being hampered because Tesla's stated claims for the engine have been difficult to reproduce in the real world.  Sonny Entrican's efforts as recently reported in the TEBA NEWS are a prime example.  For a couple of years now he has been attempting to get a single-stage 48" gas-fired turbine to self sustain, without real success.  (Self-sustained operation means that the power needed to propel the upstream screw compressor is provided by the turbine itself.)  Tesla himself had insurmountable difficulties when it came to getting a commercially viable gas turbine off the ground.  By the way, Prof. Rice cites a "wide-spread belief" that the fundamental turbine design will see greater utilization in the future based upon its durability under adverse operating conditions.  Other factors leading in this direction are the inherent simplicity of the disk-type rotor, and recent advances in materials technology.

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!!

A number of factors come into play, and to gain a basic understanding I recommend reading the book Nikola Tesla On His Work With Alternating Currents and Their Application to Wireless Telegraphy, Telephony  and Transmission of Power. 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.

In simplified terms, the basic system would consist of a large magnifying-transmitter Tesla coil (see Apparatus for Transmitting Electrical Energy) with an elevated terminal at one end and a very good ground connection at the other. Powered by a large electrical generator, the giant transmitter would pump energy into the resonating system. The receiving apparatus would be an identically tuned helical resonator also having an elevated terminal and the essential ground connection (a ground connection can be established through the use of capacitance). The receiver would tap into the resonating system extracting energy like a faucet on a pressurized water tank.

In Tesla's work on the wireless transmission of electrical energy, wireless power transmission was the icing on the cake.  His main thrust in was the development of a global system for wireless telecommunications.  There is some recent evidence indicating the communications aspect of the World-System plan is viable, but this is not the case with the transmission of electrical power in industrial quantities.  Even if it were, it is most doubtful that implementation of such a feature would be desirable at this time.

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?

There are a few books presently available where you can find the patents that I have mentioned above. One of these, Tesla's Engine — A New Dimension For Power, also contains a number of disk turbine related articles from Tesla's time, many in his own words. You may also wish to look into the Tesla Engine Builders Association website listed on the TFCBooks-Links page.

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.  Tesla's investigations in the area of high-voltage RF power processing techniques did result in the very first high efficiency, high frequency lighting ballasts.  His seminal lectures on the topic of high frequency lighting are, "Experiments With Alternate Currents of Very High Frequency and Their Application to Methods of Artificial Illumination," "Experiments with Alternating Currents of High Potential and High Frequency" and "On Light and Other High Frequency Phenomena" all to be found in the book Inventions, Researches and Writings of Nikola Tesla.  It's interesting to note that the world's first commercial fluorescent lamps, introduced by the Westinghouse Electric Company at the 1939 Chicago World's Fair, were of the low-voltage 50-60 Hz hot cathode type still in common use today.  Only since the late 1980s have more efficient high-frequency ballasts—some with great design similarities to those developed by Tesla over 100 years ago—begun to gain wider acceptance.

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. You may wish to contact the Tesla Coil Builders Association (TCBA) and ask about membership. The address is:

Tesla Coil Builders Association
3 Amy Lane
Queensbury, NY 12804

Joining the TCBA will put you in touch with a large community of people that have interests in common with your own. As a member of this group you will find assistance with all of your TC building needs.

Have you ever been to Griffith Observatory in L.A., California? We have a Tesla Coil that we obtained in 1935 from a carnival. This has always been one of the most popular exhibits in the Observatory. We demonstrate the T-Coil by having patrons hold a fluorescent tube (which lights up, of course) as we fire up the "lightning machine". 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!

P.S. I always make people listen to my history of Tesla before I show them any tricks. Unfortunately, most people don't care about the history; they just want to see the "lightning". This is the reality, and that's why I'm asking for any "tricks". When I do tricks, the people get more interested and even listen for a few seconds.

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. They include such things as the luminosity of a fine wire on a dielectric plate, glow discharge between two rings, brush discharge between two parallel wires, brush discharge through a dielectric plate, rotating pinwheel, and the lighting of a vacuum tube between two plates. Most of these can be traced back to the lectures of 1891-93, in particular the "Experiments With Alternate Currents of High Potential and High Frequency" [Inventions, Researches and Writings of Nikola Tesla] delivered by Tesla in 1892 before the Institution of Electric Engineers in London.

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. This typically consists of a single layer wire coil or solenoid with the upper end connected to a metal plate and the lower end connected to an earth ground. The tube is inserted into the ground lead. Fine tuning can be accomplished by adjusting the size of the elevated plate which can be made of aluminum foil suspended from a light weight wooden "T" shaped frame. As an alternative to the fluorescent, it is possible to light a small incandescent lamp by connecting it to a shorter secondary coil wrapped around the solenoid. If you really want to get tricky, connect a small DC permanent magnet motor to the secondary through a silicon diode bridge rectifier.

While the circuits described above are quite simple, the difficulty arises in getting them in tune with the transmitter. You might want to enlist the assistance of a local amateur radio operator with this. Also, I would like to recommend an inexpensive booklet titled Tesla Oscillator and Fluorescent Tube Driver that covers this very subject. Another good source of information is the Tesla Coil Builders Association, 3 Amy Lane, Queensbury, NY 12804-9432.

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 (Tesla called it a telautomaton) was first demonstrated to the public in 1898 at New York City's old Madison Square Garden. A patent with the long title "Method of and Apparatus for Controlling Mechanism of Moving Vessels or Vehicles" (No. 613,809) was granted to Tesla in the same year. 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. A description of this event is found early in Chapter 7 of the book Tesla: Man Out of Time.  The lecture itself is presented in Inventions, Researches and Writings of Nikola Tesla.

Tesla's two radio controlled boats were built in the 1897-98 period.  While they could withstand submersion, they had a slight positive buoyancy and no diving planes, and thus were not true submarines, as they are sometimes described.  These boats were actually surface running torpedoes—the patent shows a detonating device in the forward compartment—and could be considered a direct predecessor of present day precision guided weapons.  Remote control photo reconnaissance drones, remotely operated vehicles (ROVs) that are used in hazardous environments, and planetary exploration vehicles such as the Mars rover Sojourner all trace their lineage back to these devices.

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

It is a little known fact that Nikola Tesla is the acknowledged inventor of the electronic AND logic gate circuit, a critical element of every digital computer. In New York City in the mid 1890s Tesla's work was focused on the development of an independent remotely-controlled device—the "telautomaton."  These efforts led him to devise methods for selectively activating any of several wireless receivers (he called this "the art of individualization") that involved multiple transmissions on separate frequencies.  At the receiving end, each one of the individual frequency components had to be tuned in, in order for the receiver to respond—the AND logic function.  In June of 1899 Tesla established an experimental station at Colorado Springs where he continued his studies.  Realizing the importance of his ground-breaking techniques he gave instructions upon his return to New York that patent applications be prepared and submitted.  During the review period, the Patent Office told Tesla that another patent application for a similar concept had been received from Reginald Fessenden, and in 1902 a U.S. Patent Interference investigation was conducted concerning Tesla's wireless communications system.  In the end, Tesla's claims were supported and he was granted protection under the "System of Signaling" and "Method of Signaling" patents—both 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. These same patents also describe essential features of the spread-spectrum wireless communications techniques known as frequency-hopping and frequency-division multiplexing.  A more detailed account, including a complete transcript of the Patent Interference proceedings, can be found in the book Nikola Tesla: Guided Weapons & Computer Technology.

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.

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.

Of the myriad natural phenomena which manifest themselves in the universe, radio waves fall into a special category: things which cannot be directly observed. This helps to explain why they remained practically unknown until the 19th century when a number of important steps were taken by early investigators who developed techniques for their detection and measurement. This led to the 1886-88 experiments of Heinrich Hertz which firmly established their existence.

Nikola Tesla's contribution to all this involved reworking the primitive radio frequency generators and tuned receiving circuits which his predecessors had developed. The first step was to introduce the coupled tuned circuit into the transmitter design. Some might recognize this as the configuration of the now familiar Tesla coil, with its primary and secondary circuits both tuned to vibrate in harmony with each other. Additional work resulted in the development of receivers which also incorporated two synchronized circuits. 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 because it was anticipated by Tesla.  The U.S. Supreme Court affirmed this ruling on June 21, 1943.  It's worthwhile noting that the following definition of radio was developed as a result of this case:

A radio communication system requires two tuned circuits each at the transmitter and receiver, all four tuned to the same frequency.

To learn more about this interesting chapter in the history of wireless communications see Priority in the Invention of Radio — Tesla vs. Marconi and John Stone Stone on Nikola Tesla's Priority in Radio and Continuous-Wave Radiofrequency Apparatus.

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, the accompanying drawing of which clearly shows an energy storage capacitor and a discharge device on the primary side of a resonance transformer.  His patent "Means for Generating Electric Currents" No. 514,168 of February 6, 1894 describes a variation of this same circuit.  Between September 15, 1896 and November 18, 1898 no fewer than 17 patents were granted for equipment directly related to the production of powerful high-frequency electrical currents.  It was during that same period, on September 2, 1897, that Tesla filed his first application which was directly related to wireless transmission and reception, resulting in two patents that were subsequently issued as "Method of . . ." and "Apparatus for Transmission of Electrical Energy," both dated May 15, 1900.  On July 1, 1898 another wireless-related application was filed for the radio-controlled boat resulting in the patent, "Method of and Apparatus for Controlling Mechanism of Moving Vessels or Vehicles" issued November 8, 1898.  All of these patents appear in the book Dr. Nikola Tesla — Complete Patents.

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. In one form it consisted of a glass globe in the neck of which was sealed a glass tube. The end of the tube was blown out to form a small sphere positioned at the center of the larger globe. The connection to the power supply was made through a moderately rarified, highly conducting gas inclosed within the central tube. You can learn more about this specialized vacuum tube, the rotating brush phenomenon, and other types of single electrode tubes in Tesla's lecture "Experiments with Alternate Currents of High Potential and High Frequency" which appears in the book Inventions Researches and Writings of Nikola Tesla.  The actual description, with illustrations, appears on pages 226-230.

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.  The uppermost coil could be raised on a vertical central column and locked in place above the lower coil at the desired separation.  Tesla spoke about the static eliminator in a 1916 interview (see Nikola Tesla On His Work With Alternating Currents) saying,
   "This instrument was built [at] a recent date, but the principle involved in its operation I have employed in Colorado. It is what I call a static preventer. A great trouble, when I came to Colorado, was that I could not operate at all. You know that the static interference is today the great bane of the wireless transmission. The reason for that is defective construction of the plants, but with this invention I am enabled to even make these defective plants operate satisfactorily.
   "The principle involves the employment of a plurality of tuned circuits in series as shown [in Fig. 77]. However, any interaction of the circuits, arising from mutual induction, produces results which are exceedingly complex. The emitted note will not be pure because of the beats produced. Radio engineers are not fully appreciative of this. The instrument shown [Fig. 101] consists of coils suitably arranged in demonstration of the principle to overcome the detrimental effects."

By the way, both of the Electrical Experimenter articles can be found in the book Solutions to Tesla's Secrets.

In regards to the statement about the static eliminator having a patent, such a patent might have been issued by a country other than the United States.  A partial list of patents contained in the CATALOGUE OF TESLA PATENTS, Belgrade, 1987, shows that worldwide there were at a minimum, 221 patents issued to Tesla in 25 countries over the course of his lifetime. This figure breaks down as follows:

Argentina - 1
Australia - 14
Austria - 4
Brazil - 2
Canada - 1
Cuba - 1
Denmark - 1
Germany - 14
Great Britain -16
France - 13
India - 1
Italy - 11
Japan - 1
Hungary - 7
Mexico - 1
New South Wales - 2
New Zealand - 1
Norway - 2
Rhodesia - 1
Russia - 4
Spain - 4
Switzerland - 4
Sweden - 2
Transvaal - 1
United States - 112

While there are definitely a number more patents than those listed above, the often quoted figure of 700 patents appears to be overblown.  A statistical analysis shows the actual figure probably lies somewhere between 250-350 patents worldwide.

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?

It is possible that Nikola Tesla is best known for his remarkable statements regarding the wireless transmission of electrical power. His 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 experiments was simply to produce effects locally and detect them at a distance. By 1899 the electrical potential of his transmitter had increased to the point that more room was needed for the sake of safety. This and other considerations led him to temporarily shift his experiments to a location just outside of Colorado Springs.

It was at this Colorado "Experimental Station" 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 he even went as far as to make the following statement.

"... to make the little filament glow, the entire surface of the planet, two hundred million square miles, must be strongly electrified. This calls for peculiar electrical activities, hundreds of times greater than those involved in the lighting of an arc lamp through the human body [a more spectacular demonstration]. What impresses him most, however, is the knowledge that 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."
     [From New York Times, Oct. 22, 1907, "Possibilities of 'Wireless'" found in Tesla Said.]

It is not clear that Tesla was referring to effects produced by his large Colorado transmitter. More likely he was writing of what he believed could be done with an even bigger transmitter such as the one that he was trying to complete at Wardenclyffe in New York.

The following books will help you to learn more about Nikola Tesla's work in wireless communications and power transmission: Nikola Tesla On His Work With Alternating Currents and Their Application to Wireless Telegraphy, Telephony and Transmission of Power, Nikola Tesla — Guided Weapons & Computer Technology, the Colorado Springs Notes, and the Tesla Coil Builder's Guide to the Colorado Springs Notes.

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. If the communications facility had been completed, it is this above ground structure that would have housed a set of large coils that would have comprised the principle transmitting and receiving elements.  It is not exactly clear how Tesla planned to tune these coils 

As for the well below the tower, 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. Tesla rigged up special machines that were used to push these pipes, one length after another, outward or downward into the sandy Long Island subsoil.

After the second Wardenclyffe foreclosure took effect and 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.

A fairly good description of the underground installation as well as the tower itself is given on  pages 200-204 of the book Nikola Tesla On His Work With Alternating Currents.

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

During a celebration of his 79th birthday on July 10, 1935, Tesla made an announcement to the press of an invention called "telegeodynamics." This was a system by means of which mechanical energy could be transmitted through the ground to any part of earth. He claimed telegeodynamics could provide one-way communications, an aid to navigation for ships, and a means of locating hidden ore deposits. Implementation of a full-blown system would have involved the installation of at least one massive reciprocating mechanical oscillator with a piston weighing in at about 100 tons!

Another project from the same period of Tesla's life that received a significant amount of press coverage was a particle beam projector—the teleforce proposal. While he did make some statements about the transmission of power with this unique open-ended vacuum tube, it was intended for directing energy towards a specific target and not for broadcasting.

It is possible you are referring to an earlier project dealing with the application of alternating electrical currents to wireless communications and power transmission. This effort drew much of Tesla's attention during the period generally between 1891 and 1912. In "The Future of the Wireless Art" [Tesla Said pp. 108-110], which appeared in Wireless Telegraphy & Telephony, 1908, Tesla made the following statement regarding the Wardenclyffe project on which he was then working:

"As soon as completed, it will be possible for a business man in New York to dictate instructions, and have them instantly appear in type at his office in London or elsewhere. He will be able to call up, from his desk, and talk to any telephone subscriber on the globe, without any change whatever in the existing equipment. An inexpensive instrument, not bigger than a watch, will enable its bearer to hear anywhere, on sea or land, music or song, the speech of a political leader, the address of an eminent man of science, or the sermon of an eloquent clergyman, delivered in some other place, however distant. In the same manner any picture, character, drawing, or print can be transferred from one to another place. Millions of such instruments can be operated from but one plant of this kind. More important than this, however, will be the transmission of power, without wires, which will be shown on a scale large enough to carry conviction. These few indications will be sufficient to show that the wireless art offers greater possibilities than any invention or discovery heretofore made, and if the conditions are favorable, we can expect with certitude that in the next few years wonders will be wrought by its application."

If the above predictions were to be true, an interesting feature of Tesla's World System for global communications, had it gone into full operation, would have been its capacity to provide small but usable quantities of electrical power at the location of the receiving circuits. He predicted that further advances would have permitted the wireless transmission of industrial amounts of electrical energy with minimal losses to any point on the earth's surface. If he had been able to complete the prototype communications station on Long Island and use it to demonstrate the feasibility of wireless power transmission than construction of a pilot plant for this larger system would have begun at Niagara Falls, site of the world's first commercial three phase AC power plant.

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.  [Dr. Nikola Tesla Bibliography]
 

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? 

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.

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.

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.

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 York 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.

Was Tesla suffering from some form of autism?

Nikola Tesla dreamt of the glorious future that might be brought about by the rational application of scientific knowledge. His introspection seems to have been very much influenced by objective reality, so it would appear that he did not suffer from this malady.

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.

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."

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.