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Niagara Falls Power Project (1888)


George Westinghouse and Nikola Tesla. Seeking to make long distance electric power transmission a reality, they combined their skills, their genius and their belief in a new technology ... alternating current. Together they started a revolution that electrified the world. A Perfect Partnership.



The Niagara Falls is the result of a myriad tons of water, from time immemorial, crashing over the solid limestone cliff, with a force that reduces the limestone to boulders, the boulders to rubble, the rubble to a silt the unabated torrent seizes and carries off down the canyon it has formed and shaped through the eons in this same violent, patient manner.


The Niagara Falls Power Project came as a result of pure technological optimism in 1895 after many attempts and efforts of harnessing the power of the water falls since the first pioneer sawmill had been built there in 1725. But schemes for extracting power had never been adequately conceived.


Five years before start-up of the first large-scale power project at the falls, the method of production and distribution of the power was still undecided. The huge project was to include transmission to Buffalo. Electricity (a novel technology at the time) was only one suggestion. The other methods under consideration were pneumatic, hydraulic, and good old-fashioned mechanical.


While still a student attending school in 1875, at Austrian Polytechnic in Graz, Austria, Nikola Tesla began to think about the possibilities of alternating current.


In 1881 Tesla traveled to Budapest, hoping to work for family friends, Tivadar and Ferenc Puskas. An ambitious promoter, Tivadar had previously convinced Thomas A. Edison to give him the commercial rights to introduce inventions developed by the Wizard of Menlo Park in continental Europe. The Puskas brothers were planning to construct a telephone exchange in Budapest using Edison’s improved telephone design. Unfortunately, they were unable to hire anyone immediately. While waiting, Tesla fell seriously ill. He only recovered with the help of a college friend, Anthony Szigeti, who encouraged the sick man to walk each evening to help regain his strength.


In February 1882, during one of these strolls with Szigeti that Tesla had an epiphany about motors. As they admired the sunset, Tesla suddenly envisioned using a rotating magnetic field in his motor, a fundamental principle in physics and the basis of nearly all devices that use alternating current. Tesla struggled for the next five years to acquire the practical knowledge he needed to realize his motor.


Since his childhood, Tesla himself had dreamed of harnessing the power of the great natural wonder. In his autobiography "My inventions" he told:


"In the schoolroom there were a few mechanical models which interested me and turned my attention to water turbines".


After hearing a description of the great Niagara Falls:


“I pictured in my imagination a big wheel run by the Falls.”


He proclaimed to his uncle that one day "he would go to America and carry out this scheme.”


The working principle of his idea is a magnetic field which rotates in polarity at non-relativistic speeds. This is a key principle to the operation of alternating-current motor. A permanent magnet in such a field will rotate so as to maintain its alignment with the external field. This effect is utilised in alternating current electric motors. Synchronous motors and induction motors use a stator's rotating magnetic fields to turn rotors.


He already though about a multi-phase voltage system while studying in Graz, Austria in 1882. While on assignment to Strasburg, France (Alsace, then a part of Germany) on 1883, Tesla constructs a working brushless polyphase AC induction motor to offer his invention to a German company. It is demonstrated before the former Mayor of the town and to wealthy potential investors. Unfortunately, Tesla is unable to secure financing.


Prodigal Genius - by O' Neill - pp. 56-57:


“The Mayor brought together a number of wealthy Strassburgers. To them the new motor was shown in operation, and the new system and its possibilities described, by both Tesla and the Mayor. The demonstration was a success from the technical viewpoint but otherwise a total loss. Not one member of the group showed the slightest interes.


It was beyond his comprehension that the greatest invention in electrical science, with unlimited commercial possibilities, should be rejected so completely".


After he had helped the Puskas brothers build their telephone exchange in Budapest, Tesla moved with Tivadar to Paris, where they both went to work for the Société Electrique Edison installing incandescent lighting systems.


Nikola worked for about a year for the French branch of the Edison Electric Light Co. At the beginning of 1884, after successfully performed tasks in Strasbourg, he returned to the headquarters of the Edison Continental Company in Paris. Here he improved various electriccomponents used by the Edison Company. During this employment he conceived the idea for the induction motor and other electric equipment that used rotating magnetic fields. But he hoped in vain that the professionals would take interest in his inventions of the rotating magnetic field and asynchronous motor. His remarkable abilities were noticed by Edison's business cohort and close friend Charles Batchelor, the U.S. manager of the French branch of the Edison Company, and he advised him to seek his fortune in the New World. Since he couldn't get anyone in Europe interested in it, Tesla came to the United States to work for Thomas Edison in New York.


In June 1884, Nikola Tesla arrived in the United States. On the way to the boat he actually lost all his possessions (train ticket and personal assets) and he arrived with just 4 cents in his pocket. Anyway the USA was considered the land of the free. 


Thanks to the exceptional recommendation by Bachelor and successfully performed test given by Edison (repair of dynamo machines at the Oregon ship) Tesla was employed with Edison Machine Works Company and he became one of the chief engineers and designers. Almost as soon as he arrived at the Goerck Street facility, Mr. Thomas Edison realized the genius of the younger man's work. To this twenty-eight-year old enthusiastic expert Edison gave a very delicate job of redesigning and improvement of dynamo-machines produced in his factories for the ever-increasing market of these devices. Edison also became impressed with him after he successfully performed a number of challenging assignments. The direct current electrification era had begun in the first place with great towns such as New York. But when Tesla asked Edison to let him undertake research on AC, in particular on his concept for an AC motor, Edison rejected the idea. Not only wasn't Edison interested in motors, he refused to have anything to do with the rival current.


Tesla had expected that Edison, being such a great inventor, would perfectly understand and accept the concept of development of alternate currents devices and systems as a more convenient solution for production, transmission, distribution and use of electric energy. So for the time being Tesla threw himself into work on DC. He told Edison he thought he could substantially improve the DC dynamo. Edison told him if he could, it would earn him a $50,000 bonus. This would have enabled Tesla to set up a laboratory of his own where he could have pursued his AC interests. By dint of extremely long hours and diligent effort (his regular hours were from 10:00 am till 5:00 am of the next day), he came up with a set of some 24 designs for new equipment, which would eventually be used to replace Edison's present equipment.


But he never found the promised $50,000 in his pay envelope. When he asked Edison about this matter, Edison told him he had been joking. "You don't understand American humor," he said. In that moment he was deeply disappointed, and for that reason he left Edison's company after less than one year. Tesla only worked there for about six months and he met Edison maybe twice.


Tesla claims, in his autobiographical My Inventions, the following regarding his time at the Machine Works in NY:


For nearly a year my regular hours were from 10.30 A.M. until 5 o'clock the next morning without a day's exception. Edison said to me: "I have had many hard-working assistants but you take the cake." During this period 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.


Tesla assumed that his arc lighting system would be valuable to the Edison organization and that he would handsomely rewarded for his work. However, when that didn’t happen, Tesla quit in disgust and found new backers in Rahway, New Jersey who helped him to patent and build his own arc-lighting system. However, once the Rahway businessmen had a lighting system up and running, they fired Tesla. Destitute, Tesla returned to New York to dig ditches for $2 a day.


Fortunately, Tesla helped dig ditches for the installation of cables connecting the headquarters of the Western Union Telegraph Company with stock and commodity exchanges and he came to the attention of Alfred S. Brown who was supervising the work. Brown took a liking to Tesla and introduced him to Charles Peck, a lawyer who had just made a fortune by forcing Jay Gould to buy his Mutual Union Telegraph Company.


Applies his first patent "Commutator for Dynamo-electric Machines", followed by patents on arc-lamps regulators;


In March 1885 Tesla applied his first patents US334,823 - Commutator for Dynamo Electric Machines - January 26, 1886 (Filed May 18, 1885), US335,786 - Electric Arc Lamp - February 9, 1886 (Filed May 18, 1885) and US335,787 - Electric Arc Lamp - February 9, 1886. These patents were for an improvement in the arc lamp. He used an electromagnet to feed carbons to the arc at a uniform rate to produce a steadier light. Later he applied for patents on arc-lamps regulators and he registered his 'Tesla Arc Light Co' with an aim of implementing his inventions in the field of polyphase alternating currents. Looking for a new high-tech venture, Peck and Brown decided to back Tesla in 1886 and in April 1887, backed by a number of financiers and technicians, Tesla establishes Tesla Electric Company.


In the newly erected laboratory Tesla constructed and demonstrated his first polyphase induction motors and generators. But success was not easily achieved, as his ideas to promote (AC) alternating current was difficult to finance, and by other hand his investors weren't really interested in the development of the AC technology because its future application was still unkown and they were interested just about Tesla's Electric Arc Lamp. His design was a success, but all the money went to the investors. Tesla was soon looking for another opportunity.


Presentation of the Edison Medal to Nikola Tesla: Minutes of the annual meeting of the American Institute of Electrical Engineers, held at the Engineering Societies building - New York City - May 18, 1917:


I realized I would not have produced anything without the scientific training I got, and it is a question whether my surmise as to my possible accomplishment was correct. In Edison's works I passed nearly a year of the most strenuous labor, and then certain capitalists approached me with the project to form my own company. I went into the proposition, and developed the arc light. To show you how prejudiced people were against the alternating-current, as the President has indicated, when I told these friends of mine that I had a great invention relating to alternating-current transmission, they said: —No, we want the arc lamp. We do not care for this alternating-current.— Finally I perfected my lighting system and the city adopted it. Then I succeeded in organizing another company, in April, 1886, and a laboratory was put up, where I rapidly developed these motors, and eventually the Westinghouse people approached us, and an arrangement was made for their introduction. You know what has happened since then. The invention has swept the world.


By 1885 the Italian inventor Galileo Ferraris also builds an induction motor using a two phase configuration like Tesla. However, Ferrari believes incorrectly that such motors can never exceed an efficiency of 50%. Ferraris had concluded in an article (The electrician - December 27, 1895):


"These calculations and experimental results confirm the evident a priori conclusion that an apparatus founded upon this principle cannot be of any commertial importance as a motor"


After some research he lost interest and did not continue with the development of his machines. The famous mathematician and electrical engineer, Charles Proteus Steinmetz came to support the invention of Nikola Tesla. Once noted in his german accent:


"Ferraris built only a little toy, and his magnetic circuits, so far as I know, were completed in air, not in iron, though that hardly makes the difference" (Transactions, A.I.E.E, Vol. VIII, Pg. 591, 1891).


In the case of Ferraris's induction motor, the rotary field was produced by commutating a continuous current and by the other hand the rotary field of Tesla's induction motor was produced by splitting a single-phase alternate current into two phases by proper arrangements of self-induction or condensers (the rotating magnetic field was produced in a dynamo with multiple coils and connected to similar coils in the motor).


Ferrari's induction motor (1885) - Museum of physics (University of Cagliari)
Ferrari's induction motor (1885) - Museum of physics (University of Cagliari)
Tesla's induction motor (1884)
Tesla's induction motor (1884)


The Fig.? shows the first Tesla's induction motor, prior to the year 1884 and altho unique in construction, it developed ¼ horse power at 1800 revolutions per minute and weighed but 20 pounds.


Electro-Motors - The Electrical Review - by Nikola Tesla - April 3rd, 1891:


Fifteen or sixteen years ago, when I was pursuing my course at the college, I was told by an eminent physicist that a motor could not be operated without the use of brushes and commutators, or mechanical means of some kind for commutating the current. It was then I determined to solve the problem.


After years of persistent thought I finally arrived at a solution. I worked out the theory to the last detail, and confirmed all of my theoretical conclusions by experiments. Recognizing the value of the invention, I applied myself to the work of perfecting it, and after long continued labor I produced several types of practical motors.


Now all this I did long before anything whatever transpired in the whole scientific literature — as far as it could be ascertained — which would have even pointed at the possibility of obtaining such a result, but quite contrary at a time when scientific and practical men alike considered this result unattainable. In all civilized countries patents have been obtained almost without a single reference to anything which would have in the least degree rendered questionable the novelty of the invention. The first published essay — an account of some laboratory experiments by Prof. Ferraris — was published in Italy six or seven months after the date of filing of my applications for the foundation patents . The date of filing of my patents is thus the first public record of the invention.


No one can say that I have not been free in acknowledging the merit of Prof. Ferraris, and I hope that my statement of facts will not be misinterpreted. Even if Prof. Ferraris’s essay would have anticipated the date of filing of my application, yet, in the opinion of all fair-minded men, I would have been entitled to the credit of having been the first to produce a practical motor; for Prof. Ferraris himself denies in his essay the value of the invention for the transmission of power, and only points out the possibility of using a properly constructed generator, which is the only way of obtaining the required difference of phase without losses; for even with condensers — by means of which it is possible to obtain a quarter phase — there arc considerable losses, the cost of the condensers not considered.


Thus, in the most essential features of the system—the generators with the two or three circuits of differing phase, the three-wire system, the closed coil armature, the motors with direct current in the field, &c. — I would stand alone, even had Prof, Ferraris’s essay been published many years ago.


US381,968 - Electro Magnetic Motor - May 1, 1888 was filed on October 12, 1887 and on April 22, 1888 Ferraris published a paper in the Royal Academy of Sciences about the AC polyphase motor. Turin, only after reading about Thomson's repulsion motor.


For all these reasons Prof. Ferraris should be denied credit for the invention of the rotating magnetic field machines, not only on legal grounds but on demonstrable grounds as well. Also knowing that by the same rule Marconi was considered the father of radio, after Tesla faulted for not agressively pursuing the commertial development of radio apparatus, even if he demonstrated his wireless experiments in lectures and exibitions many years before than Guglielmo Marconi.


US381,968 - Electro Magnetic Motor - May 1, 1888 (filed on October 12, 1887)
US381,968 - Electro Magnetic Motor - May 1, 1888 (filed on October 12, 1887)


The Edison system used direct current, or DC. Direct current always flows in one direction and is created by DC generators. Edison was a staunch supporter of DC, but it had limitations. The biggest was the fact that DC was difficult to transmit economically over long distances.


Edison knew that alternating current didn't have this limitation, yet he didn't think AC a feasible solution for commercial power systems. Elihu Thomson, one of the principals of Thomson-Houston and a competitor of Edison, believed otherwise. In 1885, Thomson sketched a basic AC system that relied on high-voltage transmission lines to carry power far from where it was generated. Thomson's sketch also indicated the need for a technology to step down the voltage at the point of use.


The DC transmission problem was fundamental. Based on Ohm's Law, efficient and economical transmission requires high voltage (raising the voltage causes increased flow of current, while the resistance remains constant, thus lowering the resistance per unit flow of current). Too high a voltage for practical uses, such as the operation of lights or motors.


With a transformer, alternating current can easily be "stepped up" to high voltages for transmission, or "stepped down" to lower voltages for manufacturing and domestic uses. This cannot be done with direct current.


Secondary generator Gaulard and Gibbs first type with iron core straight open (1884)
Secondary generator Gaulard and Gibbs first type with iron core straight open (1884)

By that time the key to electrical power distribution, was a power transformer developed by Lucien Gaulard and John Dixon Gibbs which was demonstrated in London in 1881, and attracted the interest of Westinghouse. The Gaulard-Gibbs design was one of the first that could handle large amounts of power and was easily manufactured.


William Stanley Jr. was an electrician who worked with tele keys and fire alarms of an early manufacturer which was investigating the AC current and in 1884 went to work in Pittsburgh with Westinghouse to solve some problems in AC distribution. He lost a great deal of time trying to convert DC to AC power for experiments because he had no alternator to work with (like Ferraris's experiments).


In 1885, Westinghouse imported a number of Gaulard-Gibbs transformers and a Siemens primitive AC generator from England to develop some experiments at his home in Pittsburgh. With this material Westinghouse instructed Stanley and his assistants, Albert Schmid and Oliver B. Shallenberger, to investigate on the Gaulard and Gibbs system to determine the commercial value and to begin experimenting with AC networks. Albert Schmid was a Swiss mechanical and electrical engineer who had worked on some of the earliest dynamos and arc lamp systems in Europe and Oliver B. Shallenberger was another engineer and inventor who also worked for Westinhouse since 1884.


In the autumn of 1884, Károly Zipernowsky, Ottó Bláthy and Miksa Déri (ZBD), three engineers associated with the Ganz factory, had determined that open-core devices were impracticable, as they were incapable of reliably regulating voltage. In their joint 1885 patent applications for novel transformers (later called ZBD transformers), they described two designs with closed magnetic circuits where copper windings were either wound around iron wire ring core or surrounded by iron wire core. In both designs, the magnetic flux linking the primary and secondary windings traveled almost entirely within the confines of the iron core, with no intentional path through air (see Toroidal cores below). The new transformers were 3.4 times more efficient than the open-core bipolar devices of Gaulard and Gibbs.


US351,589 - System of electric distribution - Oct. 26, 1886. Patent used by Westinghouse company.
US351,589 - System of electric distribution - Oct. 26, 1886. Patent used by Westinghouse company.

The Ganz factory in 1884 shipped the world's first five high-efficiency AC transformers. This first unit had been manufactured to the following specifications: 1,400 W, 40 Hz, 120:72 V, 11.6:19.4 A, ratio 1.67:1, one-phase, shell form.


The ZBD patents included two other major interrelated innovations: one concerning the use of parallel connected, instead of series connected, utilization loads, the other concerning the ability to have high turns ratio transformers such that the supply network voltage could be much higher (initially 1,400 to 2,000 V) than the voltage of utilization loads (100 V initially preferred). When employed in parallel connected electric distribution systems, closed-core transformers finally made it technically and economically feasible to provide electric power for lighting in homes, businesses and public spaces.

The prototype transformer is on display at the Széchenyi István Memorial Exhibition, Nagycenk, Hungary
The prototype transformer is on display at the Széchenyi István Memorial Exhibition, Nagycenk, Hungary


The other essential milestone was the introduction of 'voltage source, voltage intensive' (VSVI) systems' by the invention of constant voltage generators in 1885. Ottó Bláthy also invented the first AC electricity meter.


The management of Thomson Houston realized that alternating current would be the way of the future and pressed Thomson to provide the technical solutions. He had been working on the problem since 1885 but was blocked by the series connection patented by Gibbs and Gaulard. His efforts were to make self regulating transformers connected in parallel. An AC generator was installed in the Thomson Houston factory in Lynn to provide incandescent lighting and to test the system.


In the Spring of 1885, before opening his electric factory, George Westinghouse purchased the rights in the United States for the use of the Gaulard and Gibbs transformer patents that would "transform" the voltage of alternating current, so that electricity could be carried over long distances at high voltages, then stepped down to the proper voltage for its intended use. Some features of the device he had acquired were impractical, but he hired William Stanley Jr. as chief engineer and other staff for the planned transformer operation and in a few weeks they already worked out a complete new design. He designed and constructed the first commercially-used transformer.


Stanley improved the efficiency and methods of construction by using sheet steel clamped together in a rectangular form. On two sides of the rectangle he wound copper bar induction coils with one coil having five times more turns than the other. The completed transformer had a 500 volt primary and a 100 volt secondary. Stanley was issued US method of construction patent US349,611 A - Induction coil - 21 Sep 1886. It was easy to produce, relatively inexpensive and easy to adjust. It had to be wind to form a core of E-shaped plates in step-up and step-down variations, the central projections of each successive plate being alternately inserted through rewound coils from opposite sides, thus permitting separate winding and consequently the better insulation of the coils.


In a rented plant in Pittsburgh's Garrison Alley the Westinghouse Electric Company was born in 1886. Using the financial success of his air brake operation George Westinghouse and his engineers started the design and building of electrical equipment that used alternating current.


Westinghouse was still flirting with DC power and that infuriated the moody inventor William Stanley Jr. They weren't ready for a divorce so they got a trial separation in December of 1885. Under the new deal Stanley worked out of an office in Massachusetts.


It was first used in Barrington, Massachusetts in March 1886, where he rented a deserted rubber mill for the electrification of the downtown area using an advanced AC power system. he had lit up a small neighborhood with his transformer and an AC generator. The book Networks Of Power by Thomas Parke Hughes described it in detail:


"The length of the transmission circuit from central station laboratory to village center was about 4,000 feet. Connected to it were thirteen stores, two doctors' offices, one barber shop, the telephone exchange, and the post office."


He purchased a 25 horsepower boiler and steam engine to connect the Siemens alternator that Westinghouse imported from England and they located it at the old rubber mill near Cottage Street in Great Barrington, to provide the power for Stanley's pioneering distribution system. This power system was actually placed in operation on March 6, and the following two weeks were utilized for "research and development" before the public demonstration.


In this facility he constructed 26 transformers and used four of these to set up lights in Great Barrington. In the village he lit 13 stores, 2 hotels, 2 doctors' offices, 1 barbershop, and the telephone and post offices. The distance from the generator to the center of town was about 4000 feet. Ten transformers were sent to Pittsburgh to demonstrate a system about two miles long. The success of hydropower plants was evident with additional generating stations built along the Niagara River.


Using this as research materials William Stanley Jr. built his first transformer and it was a lot like the Gaulard and Gibbs's model. For the record, he also had access to the patent papers on the ZBD transformer. Stanley designed and built his own transformers for this installation. He demonstrated their ability to both raise and lower voltage by stepping up the 500-volt output of the Siemens generator to 3000-volts, lighting a string of thirty series-connected 100-volt incandescent lamps, and then stepping the voltage back down to 500-volts.


US349,611 A - Induction coil - 21 Sep 1886
US349,611 A - Induction coil - 21 Sep 1886
William Stanley’s transformer, used in the electrification of downtown Great Barrington, MA, in 1886. The system was virtually identical to the system used for the distribution of electric power today.
William Stanley’s transformer, used in the electrification of downtown Great Barrington, MA, in 1886. The system was virtually identical to the system used for the distribution of electric power today.


The spread of Westinghouse and other AC systems triggered a push back in late 1887 by Thomas Edison (a proponent of direct current) who attempted to discredit alternating current as too dangerous in a public campaign called the "War of Currents".


In April 1888 Oliver B. Shallenberger invented an induction meter for measuring alternating current (ampere-hours), a critical element in the Westinghouse AC system.


Early AC systems had a major disadvantage that there was no commercially available AC motor. This shortcoming was solved in fairly short order when the word of the extraordinary Tesla patents reached the academic world, when he was issued his first set of patents for a comprehensive system of AC generators, transformers, synchronous motors and induction motors for the transmission and utilization of two or more phases, what came to be known as the polyphase system. And so it came to pass that the inventor was invited to lecture before the American Institute of Electrical Engineers. George Westinghouse became aware of Tesla in May1, 1888 due to his remarkable speech in Pittsburgh when Tesla introduced his motors and electrical systems in a classic paper, “A New System of Alternate Current Motors and Transformers” which he delivered before the American Institute of Electrical Engineers.


The engineer Elihu Thomson was there and some in the group and he was impressed. The single-circuit induction motor developed by Thomson-Houston still required a commutator, and was still very inefficient. Elihu Thomson rose from his seat and, after praising Tesla's: "new and admirable little motor" he declared that he had for some time been working along similar lines toward the same goal:


"The trials which I have made have been by the use of a single alternating circuit, not a double alternating circuit".


When Tesla's agents offered the patents to Thomson-Houston, he dissmissed them as not worth the cost of securing them. He may actually believed this or he may has seen them as a threat to his own system. On the other hand, acquiring the patents would imply the contract with Tesla in his company, but Thomson didn't like other inventors mucking around his domain. Anyway, Thomson followed Edison's lead in rejecting the doorway to the future proferred by Tesla.


Westinghouse promptly dispatched Guido Pantaleoni to Italy to buy the Ferraris's patents, paying the munificient sum of 5000 lire - $1000 for such right. Just as he had done a year earlier in securing patent control over AC transformers. However, closer inspection of Tesla's patents convinced the American entrepreneur that the Italian patents would be of little use. Shallenberger expressed his concern to Westinghouse that the Tesla patents might prevent the company from succesfully development an AC motor. In response Westinghouse dispatched Henry. M Byllesby, vice president of Westinhouse Electric and Thomas B. Kerr, general counsel, to New York in late May 1888 after one week of Tesla's lecture and he did not commit the same mistake as Thomson or Edison. In fact Tesla's progress on the motor was ahead of Oliver Shallenberger's 3 phase electric motor. Two months later, George Westinghouse acquired the patent rights and Tesla’s services and he also introduces the induction ampere-hour meter for alternating current developed by Oliver B. Shallenberger.



Fig. 6.—Diagram illustrating Principle of Tesla Motor.
Fig. 6.—Diagram illustrating Principle of Tesla Motor.


Tesla conceived that by providing the armature of his generator and the field of his motor with two more sets of coils, connected so as to form distinct circuits, he would be able to produce a progressive shifting of the magnetic poles of the motor field, and thus drag around an armature capable of magnetic induction and placed within the sphere of influence of his rotating field. This method of operation will be clearly understood from the diagrammatic sketch A (Fig. 6) and the illustration (Fig. 7) showing a diagram of the connections of the motor and generator circuits. Considering the latter first, M is the motor and G the generator. The armature A of the generator is wound with two sets of coils, B and B', brought out through the shaft and connected with the contact rings b b and b' b'.


Fig. 7. — Diagram of Tesla Motor Connections.
Fig. 7. — Diagram of Tesla Motor Connections.


The field magnet of the motor consists of the iron ring R, also wound with two sets of coils, C C and C' C', the diametrically opposite coils being connected together in series. The generator coils B and the motor coils C' C' it will be seen are included in one circuit L, and the remaining generator coils B' and the motor coils C C in another circuit L'. The armature of the motor consists simply of a disk of iron cut away at the sides, which becomes a magnet by induction when the motor field is energized. Turning to Fig. 6, B and B' represent the coils of the generator armature and C and C' those of the motor field as in Fig. 7. When the generator coils are in the position shown in the first diagram the coil B is generating no current and B' is generating its maximum amount. The coils C of the motor field, which are included in the circuit of B', are therefore traversed by their greatest current and produce magnetic poles in the iron ring R at N and S. As the generator armature revolves, B is brought to a position in which it is generating current, and when this movement amounts to one eighth of a revolution the circle will be in the position shown in the second diagram of the figure. Each of the pair of coils C and C' will now tend to set up poles in the ring R of the motor ninety degrees from each other, and as their action is equal and opposite, the position of the poles will be determined by the resultant of the magnetic forces acting on the ring, and the poles will therefore be shifted around the ring an eighth of a revolution. They will be shifted another eighth when the generator armature reaches the position shown in the last diagram, and will be successively displaced around the ring R as this armature revolves until a complete revolution has been made, when the parts are in their original position and ready to repeat the same cycle of operations.


The principle of the rotation of the magnetic poles had been applied by Mr. Tesla to a great variety of constructions. He had designed machines in which the field magnetism remains fixed and that of the armature is shifted, and others again in which there is a progressive shifting of the magnetic poles of both the field and armature in opposite directions. He had also found that the motor armature may consist of sets of closed coils, currents being developed in them by induction, and by making the induced portion of the generator stationary and the field revolving he has been able to produce apparatus free from all movable electrical contacts. In operating motors of this character Mr. Tesla usually employed a generator with multiple armature circuits as described above; but in the course of his experiments he discovered that the ordinary continuous or direct current machine could by slight alterations be made to furnish an alternating multiphase current as well as and in addition to the direct current. To accomplish this he found it was only necessary to add to the machine a pair of collector rings for each circuit of the multiphase current, and connect them with the proper armature coils. If, for instance, he desired to produce a two-phase current requiring two circuits from his generator to his motor, one circuit would include a set of coils in the armature of the generator that were passing through the position in which the maximum current was being produced, and the other a set of coils in which at the same time the minimum current was being generated. The phases of the current would then follow each other in the same order as in the previous machines with distinct circuits on the armature. With this form of machine a multiple- phase alternating current, it will be seen, can be taken off from the collector rings, while a direct current can be taken from the commutator, and a part or the whole of this direct current be sent through the field coils to energize them and then put to any use for which such currents are suitable.

One day Westinhouse visited Tesla’s laboratory and was amazed at what he saw. Tesla had constructed a model polyphase system consisting of an alternating current dynamo, step-up and step-down transformers and A.C. motor at the other end. The perfect partnership between Tesla and Westinghouse for the nationwide use of electricity in America had begun.


Nikola Tesla on his work with alternating currents and Their Application to Wireless Telegraphy, Telephony and Transmission of Power: An Extended Interview - Leland I. Anderson, Editor:


In order to increase the number of breaks, I employed currents of different phase. I had in my laboratory, permanently, a two-phase dynamo and could get phases between; that is, from two phases, 90 apart, I could obtain four phases, 45 apart. Here is an arrangement shown as I had it, working with three phases (60 apart, and could obtain six phases, 30 apart), and later on I had one with four phases (45 apart, and could obtain eight phases 22 1/2 apart). You see, as I multiplied the number of the phases, I increased the number of the fundamental discharges.


This I employed already in the 35 South Fifth Avenue laboratory, because I remember that I gave entertainments to several scientific societies and it was then present there. I know on one occasion there was the Society of Architects, and another, the Electrotherapeutic Society, and then I had distinguished men like Mark Twain and Joseph Jefferson -- I gave them a demonstration which was published in Martin's article in the Century Magazine of April 1895, and I know that on these occasions I used a two-phase arrangement. Later on I made it four phase. That apparatus existed, therefore, prior to the destruction of my laboratory in 1895.


Multi-phase generator with mechanical break.  Experiments in the laboratory at 35 South Fifth Avenue and subsequently.
Multi-phase generator with mechanical break. Experiments in the laboratory at 35 South Fifth Avenue and subsequently.
Three phase variable reluctance motor - Tesla patent 381,968 filed Oct 12, 1887
Three phase variable reluctance motor - Tesla patent 381,968 filed Oct 12, 1887


He never developed his inventions with any comertial intention, and he allways had the confidence that the necessary fundings would materialize somehow by its own importance. In the case of the Alternating Current, the opportunity came in late 1893 from the important inventor and buisness man from Pittsburgh, George Westinghouse, who made his fortune by manufacturing his invention of air brakes for the burgeoning railroad industry. Westinghouse was awarded the contract to create the powerhouse and Tesla told to the industrialist about his idea for the polyphase system, which would allow alternating current (AC) electricity to be transmitted over large distances.


Westinhouse was very interested in the concept developed by Tesla but the exact terms and conditions of the agreement does not appear in the historical records. Many sources suggested that Tesla received $ 1 million for his more than 40 patents but the most credible record is probablly that he was paid $60,000 with 90% being in Westinghouse stock and a royalty of $2.50 per installed kW.


When Byllesby and Kerr expressed an interest in buying the patents for Westinghouse, Peck informed them that a San Francisco capitalist had offered 2000.000 $ plus a royality of $2.50 per horsepower for each motor installed.


"The terms, of course, are monstruous" Byllesby told Westinhouse "I told them that there was no possibility of our considering the matter seriously". "In order to avoid giving the impression that the matter was one which excited my curiosity I made my visit short".


Westinghouse once commented:


"The price seems rather high, but if it is the only method for operating a motor by the alternating current, and if it is applicable to street car work, we can unquestionably easily get from the users of the apparatus whatever taxes put upon it by the inventors"


In addition, he hires Tesla as a consultant for his company for one year and he moved to Pittsburgh in July 1888 in order to put his AC motor designs into production. While in Pittsburgh, Tesla left Szigeti in New Yorkwhere he continued to work on several motor patents that Tesla had not assigned to Westinghouse.


During his time in Pittsburgh, Tesla worked closely with Shallenberger and some other important engineers and inventors and he developed a great admiration for George Westinghouse.


Tesla initially worked on improving two polyphase motors that he brought from New York, anticipating that Westinghouse would develop a whole new polyphase system, using four wires to connect the generators and motors. Since his motors worked best on low frequencies, Tesla set up his motors to run on 50 cycles and he experimented with new transformer designs. The Westinghouse designs were using 133 cycles so that consumers wouldn't complain about their incandescent lamps flickering. Tesla finally agreed to work a split-phase version that could be put into production. He and the other Westinghouse engineers adapted the motor by increasing the amount of coper-wire in the rotor and replacing the wrought-iron cores of the rotor and stator with soft Bessemer steel. The change to steel cores alone doubled the work of a typical motor could preform and the Westinghouse company treated this discovery as a secret it jealously guarded for years. Tesla also worked with the chief Westinghouse designer Albert Schmid, to develop a standard frame for the stator that could be easily cast and machined. While working on these changes, Tesla prepared the patents for Westinghouse and in 1889 he filed fifteeh patents. In terms of patents this was the most productive year in his career *.



Tesla usually didn't put his ideas in writing or sketches and the engineers in Pittsburgh had to improve original patents as they were under the gun to get projects completed. The main problem that plagued the Tesla design was starting the motor under load in small stations. A few years later (in 1893) Charles Proteus Steinmetz working as independent contractor was involved in fixing some thermal/electrical issue. Advancing studies begun by Nikola Tesla (See the Tesla patent US417,794 - Armature for Electric Machines - A. Schmid & N. Tesla - December Dec 24, 1889 ), Steinmetz's research on hysteresis (a magnetic phenomenon that caused power loss in motors) was applied to the design of AC circuits, and resulted in precise calculations of magnetic resistance which revolutionized AC circuit theory and analysis.


US417,794 - Armature for Electric Machines - A. Schmid & N. Tesla - December Dec 24, 1889
US417,794 - Armature for Electric Machines - A. Schmid & N. Tesla - December Dec 24, 1889


In 1889 the Westinghouse Electric Company renames itself as the Westinghouse Electric & Manufacturing Company. By the same year the Niagara Falls company made financing arrangements with a banking group that comprised J.P. Morgan, Brown Brothers, Windslow and Lanier & Co. Before Windslow, Lanier agreed to participate, it had send a partner, Edward Dean Adams to investigate. Niagara Falls Power Company, a descendant of Schoellkopf's firm, formed the Cataract Company headed by Edward Dean Adams, with the intent of expanding Niagara Falls power capacity.


Tesla left the Westinghouse plant in the fall of 1889, and he had immediately turned to the next phase of his development of the alternating-current field: a new system of distributing energy by means of high-frequency alternating currents which would be a far more magnificent discovery than his polyphase system. Within the next two years he had explored the principles by which energy could be distributed broadcast without the use of wires, and these he had demonstrated with powerful coils in his laboratory. The distribution of intelligence, later called 'wireless', was but a single phase of his world-wide system.


On 1890 Adams became the president of the cataract construction and he soon left for Europe (supposedly not to find financing but to obtain technological information). He called Rothschild in London to explain the plans for the utilization of Niagara falls and the british banker reccomended engineers and then as Adams recalled, the banker asked:


"I suppose you are not ready with your financial plans?"


"yes" replayed the president Adams - "they had been adopted to a preliminary extent... All previous efforts to utilize Niagara power in a important way have been failures, but we believe that science has so advanced that, with its skillfull use, it soon may be possible to harness Niagara upon comertial basis".


Adams told to Rothschild:


"we have not come for money, but for advice. We wish to begin by investing in the counsel of your scientists and engineers"


Lord Rothschild found this request from an American rare, and according to Adams made an initial suscription of £5.000 as a result of the interview, but in fact nothing was rare and the president was just opening the way for foregin capital.


A flood destroyed the Willamette Falls DC power station. This unfortunate event paved the way for the first long distance transmission of AC electricity in the world when Willamette Falls Electric company installed experimental AC generators from Westinghouse in 1890. That same year, the Niagara Falls Power Company (NFPC) and its subsidiary Cataract Company formed the International Niagara Commission composed of experts, to analyze proposals to harness Niagara Falls to generate electricity. The commission was led by Sir William Thomson (later Lord Kelvin) and included Eleuthère Mascart from France, William Unwin from England, Coleman Sellers from the US, and Théodore Turrettini from Switzerland. It was backed by entrepreneurs such as J. P. Morgan, Lord Rothschild, and John Jacob Astor IV. Among 19 proposals, they even briefly considered compressed air as a power transmission medium, but preferred electricity. Anyway they could not decide which method would be best overall.


In 1890 George Westinghouse recommended that the best way to transport Niagara Falls power to Buffalo would be by compressed air (compressed-air or water mains or steel cables on posts and pulleys the 22-mile distance from Niagara Falls to Buffalo). Westinghouse was likely to know. As the inventor of the air brake, he was the acknowledged expert on pneumatic systems. And of late he had turned his attention to electricity. In 1886 he had organized the Westinghouse Electric Company. By 1890, the company was operating 300 central generating stations.


When Nikola Tesla invented the three-phase system of alternating current power transmission, distant transfer of electricity became possible, as Westinghouse and Tesla had built the AC-power Ames Hydroelectric Generating Plant in Telluride in 1890 and proved it effective transmitting electricity to 2.6 miles (4.2 km) by using a motor-driven stamp mill at the Gold King Mine. It began operation in 1891.


Interior of the Western Colorado Power Company's Old Ames plant' scene in 1891 .
Interior of the Western Colorado Power Company's Old Ames plant' scene in 1891 .


Edison's DC distribution system consisted of generating plants feeding heavy distribution conductors, to customer loads primarily lighting and motors. The system operated at the same voltage level throughout; for example, 100 volt lamps at the customer's location would be connected to a generator supplying 110 volts, the margin allowed for some voltage drop in the wires between the generator and load. The voltage level was chosen for convenience in lamp manufacture; high-resistance carbon filament lamps could be constructed to withstand 100 volts, and to provide lighting performance economically competitive with gas lighting. At the time it was felt that 100 volts was not likely to present a severe hazard of fatal electric shock.


To save on the cost of copper conductors, a three-wire distribution system was used. The three wires were at +110 volts, 0 volts and −110 volts relative potential. 100-volt lamps could be operated between either the +110 or −110 volt legs of the system and the 0-volt "neutral" conductor, which carried only the unbalanced current between the + and − sources. The resulting three-wire system used less copper wire for a given quantity of electric power transmitted, while still maintaining (relatively) low voltages. Even with this innovation, the voltage drop due to the resistance of the system conductors was so high that generating plants had to be located within a mile (1–2 km) or so of the load. Higher voltages could not so easily be used with the DC system because there was no efficient low-cost technology that would allow reduction of a high transmission voltage to a low utilization voltage.


Unable to challenge AC electricity on technical merits, Edison turned to using scare tactics instead and carried out a campaign to discourage the use of alternating current, including spreading disinformation on fatal AC accidents, publicly killing animals, and lobbying against the use of AC in state legislatures. "Just as certain as death (AC power) will kill a customer within six months," he declared. Leaflets about the dangers of AC current were printed and distributed. Lobbying efforts were made in New York State to limit legal levels of electricity to 800 volts, making AC distribution impractical "as a matter of public safety". Perhaps most horrifying, though, were Edison's weekend demonstrations of the dangers of Tesla's work. Taking one of the frightened pets stolen from the streets of West Orange, Edison would place it on a sheet of metal, bring forth two wires attached to an AC generator, and announce to spectators:


"Ladies and gentlemen, I shall now demonstrate the effects of AC current on this dog."


Edison directed his technicians, primarily Arthur Kennelly and Harold P. Brown, to preside over several AC-driven killings of animals, primarily stray cats and dogs but also unwanted cattle and horses. Acting on these directives, they were to demonstrate to the press that alternating current was more dangerous than Edison's system of direct current. He also tried to popularize the term for being electrocuted as being "Westinghoused". Years after DC had lost the "war of the currents," in 1903, his film crew made a movie of the electrocution with high voltage AC, supervised by Edison employees, of Topsy, a Coney Island circus elephant which had recently killed three men.


The Edison's intention to disparage the system of alternating current led to the invention of the electric chair. Harold P. Brown, who was being secretly paid by Edison, built the first electric chair for the state of New York to promote the idea that alternating current was deadlier than DC.


When the chair was first used, on August 6, 1890, the technicians on hand misjudged the voltage needed to kill the condemned prisoner, William Kemmler. The first jolt of electricity was not enough to kill Kemmler, and only left him badly injured. The procedure had to be repeated and a reporter on hand described it as "an awful spectacle, far worse than hanging." George Westinghouse commented:


"They would have done better using an axe."


Mikhail Dolivo-Dobrowolsky (Russian, naturalized Swiss), chief electrician at the AEG in Berlin used the basic ideas of Tesla and constructed the first three-phase cage induction motor. In the beginning of 1889, his first motor is running properly. His system was displayed for first time in Europe at the International Electro-Technical Exhibition of 1891, where Dolivo-Dobrovolsky used this system to transmit electric power at the distance of 176 km with 75% efficiency.


Mr. Hering wrote in the article Mr. Tesla And The Drehstrom System - Electrical World - February 6, 1892:


"Dobrowolsky, though he may have been an independent inventor, admits Tesla's work is prior to his invention. The modesty of both of these gentlemen would, I feel sure, lead to a clear understanding. Regarding the subject of priority it may be of interest here to say that in a conversation with Prof. Ferraris last summer that gentleman told me with very becoming modesty that, although he had experimented with the rotary field several years before Tesla's work was published he did not think it was possible that Tesla could have known of his work and he therefore believed Tesla invented it entirely independently. He also stated that Tesla developed it much further than he (Ferraris) did".


Dolivo-Dobrowolsky's first three-phase cage-induction motor, 1889 Illustration from ETZ, 1917 [9]
Dolivo-Dobrowolsky's first three-phase cage-induction motor, 1889 Illustration from ETZ, 1917 [9]


The construction of Niagara falls power station began in 1892 with an extensive tunnel systems at ground level and below ground level on a 21 ft. high 18 ft. wide tunnel to capture Niagara waters for the power plant. The tunnel took 3 years to build.


For Westinhouse corporation, Schmid, Scott, and Lamme could confer with Tesla, while Stillwell and Schallenberger brooded, and the money men reluctantly agreed to dismantle the very lucrative but outmoded Gaulard-Gibbs machinery.


At the beginning of 1893 Westinghouse engineer Benjamin Lamme had made great progress developing an efficient version of Tesla's induction motor and Westinghouse Electric started branding their complete polyphase phase AC system as the "Tesla Polyphase System", nothing how they believed Tesla's patents gave them patent priority over other AC systems.


Steinmetz was hired by General Electric to decipher the Tesla Patents. For the GE the situation was complex because they had hoped that someone like Steinmetz or Thomson could come up with a competing design, but they hadn't realized that Tesla held all the fundamental patents. Tesla simply understood the foundation and any company couldn't proceed without him. There was no other electrical system.


By the same year, George Forbes was hired in the Westinhouse company as a technical consultant and in May 1893 he convinced the company to build a hydroelectric system based on polyphase alternating current. Westinghouse Electric was subcontracted to build 5,000 horsepower (3,700 kW) 25 Hz AC generators, based on the work of Nikola Tesla and Benjamin G. Lamme. The turbines were to be installed into House No.3 by the I. P. Morris Company of Philadelphia, Pennsylvania based on a plan from the Swiss company of Faesch and Piccard.


In 1893 Tesla already patented different types of his alternating current electro-magnetic motors & generators but also different methods and systems of electrical power transmission and used them to light the World Columbian Exposition in Chicago in the same year. Tesla and Westinghouse were already involved in the design and installation of generators of the polyphase type. The contract came as a result of the competition spearheaded by the international Niagara Falls Commission, with cash prizes totaling $20,000 for the best plan for harnessing the falls.


The work of the Niagara falls Power Project Company, demanded from his technical advisors skill, vision and judgement of a high order. Fortunately, the management of the company was eminently wise and far-sighted and under its direction the minds of a selected group of the ables scientists in America and Europe were brought to bear upon the problem of utilizing the power of the great falls. From Europe came Lord Kelvin, Mascart, Turrettini, Unwin, and Forbes. From America came Sellers, Herschell and Rowland. Plans and suggestions were obtained also from many others at home and aboard. 


The commission, charged with planning the power project, had solicited proposals from experts around the world only to reject them all. The schemes ranged from a system using pneumatic pressure to one requiring ropes, springs and pulleys. And there were proposals to transmit DC electricity, one endorsed by Edison. With more than a few parties claiming the rights to various parts of the alternating current system, there was backstabbing and counter claims and more than a little industrial theft of ideas. Tesla advised Adams that a two phased system would be the most reliable, and that there was a Westinghouse system to light incandescent bulbs using two phase alternating current. At the head of the commission was Lord Kelvin, the famous British physicist, who had been as opposed to alternating current as Edison until he attended the Chicago Exposition in 1893. Now, a strong convert to AC, Kelvin and his commission asked Westinghouse to use alternating current to harness the power of the falls.


In the end it was Tesla’s patents that won the day. The Westinghouse Company was chosen to provide the powerhouse and alternating current system, while the General Electric Company was awarded construction of the transmission lines.


Edward Dean Adams made this statement with regard to Westinghouse's AC research relative to development of Niagara Power:


"The issuing of the Tesla polyphase patents in May, 1888,was followed a year later by the organization of the Cataract Construction Company (and its affiliate the Niagara Falls Power Company) which undertook the investigation of methods of developing Niagara Power. Niagara plans and alternating-current machinery developed simultaneously and in less than a decade they mutually contributed to the inauguration of modern hydro-electric power service."



To start with the project it was necessary for Tesla to devote some time to develop the design of the engines in Pittsburgh plant, and then the production could start up. During that period of time, Tesla could not avoid many conflicts that arose in converting theoretical and pilot plant design to full scale production and gladly returned to New York at the end of the year. The construction period was traumatic for engineers, mechanics and workers, but it weighed most heavily on investors.


The project approached completion after a five-year nightmare of doubt and financial crises but Tesla had not doubted the results for a moment. The investors, however, were not at all sure the system would work. While the machines were running smoothly in Tesla's three-dimensional imagination, they were still unproved and expensive. During development of the poly-phase motor there was a re-design and alternations from 133 Hz. or cycles per second (the more or less standard frequency for the early single-phase systems) to 60 Hz. This remains the standard North American frequency. Tesla also developed several “split phase” designs for motors for the single-phase systems.


Westinghouse started the development of three-phase motors in 1892, which lead to success in 1893.


The inventor was happy again in his laboratory and the manufacture of the motors began soon afterwards. During this period of time the inventor dedicated so much effords to create new inventions and he applyed for a number of forty-five U.S. Patents.



Laboratory where Tesla and Westinghouse engineers developed apparatus for AC systems. The exhibit shows his "Egg of Columbus," which stood on end when the table it rested on was magnetically excited by AC. Another smaller table with ball can be seen to the left; to the right, an early high-frequency machine.



Columbian exposition 1893. Westinhouse electric & manufacturing Co. Tesla polyphase system
Columbian exposition 1893. Westinhouse electric & manufacturing Co. Tesla polyphase system


The World Columbian Exposition was the World's Fair commemorating 400 years since Christopher Columbus set foot in the New World. Located on Lake Michigan to facilitate access by sea, road and rail. It was a gathering of ideas, men and technologies from every quarter of the globe, with each country contributing its best of their industrial, cultural, commercial and educational enterprises. The Renaissance style of the exposition buildings was unsurpassed by its architecture beauty. The Exposition itself was a work of art. It was a brilliant spectacle of science, art and industry. All the world has its pilgrimage to Columbian Exposition in 1893.


Westinghouse became dedicated to promoting the polyphase alternating current system and felt that this was his best chance to introduce it to the public at large. The exposition was the greatest event in America and in the world at that time. General Electric Company (Edison’s and Morgan’s company) first bid to light the fair for $1.8 million. That bid did not go over well. The two did a second bid worth $554,000. Unbeknownst to General Electric, George Westinghouse, armed with Tesla’s new induction motor, proposed to light the fair for $399,000. The ingenious promoter Westinghouse outbid Edison for the contract to power the expositions lighting and electrical systems, and the company and the AC technology recieved a widespread positive publicity.


The exposition company was set to save about $1,000,000 but was taking a serious risk on Westinghouse’s ability to deliver on-time.


When Westinghouse was notified of his winning bid, he attempted to purchase the necessary longer-life lamps from Edison-G.E. However, he found that his purchase order was rejected. No G.E. lamps were available to him, but less than a year remained to fulfill the contract. The courts sustained this blockage and refused to require Edison-G.E. to license the Westinghouse Electric Company for manufacture or to sell lamps to them.


The need for a non-infringing lamp was immediate and urgent. Fortunately, Westinghouse engineers were working on a 2-piece variation of the Sawyer-Man lamp. This lamp did not use the 1-piece Edison fused-glass seal but instead used a ground-glass “stopper” mated to the bulb envelope for sealing. Thus originated the Westinghouse “double stopper light bulb”. This newly designed Westinghouse light bulb was invented by Reginald Fessenden. He ingeniously replaced Edison's delicate platinum lead-in wires with an iron-nickel alloy and therefore greatly reducing the cost and increasing the life of the lamp. Trials indicated that the lamp would have a limited lifetime, but adequate for the exposition and long enough for his other needs until the Edison patents expired. Facilities to produce 250,000 lamps were ramped-up and the Fair opened on-time to everyone’s joy and amazement.


Stopper and bulb of new Westinghouse lamp. The Electrical Engineer, Vol XV, No 248, Feb 1, 1893, pg 108
Stopper and bulb of new Westinghouse lamp. The Electrical Engineer, Vol XV, No 248, Feb 1, 1893, pg 108


On May 1, 1893, President Grover Cleveland pushed a button and near 100,000 incandescent lamps illuminated the White City. Westinghouse’s tactics paid off immediately and immensely. Over 27 million people came through the gates of the fair. Over Two Hundred thousand electric light bulbs were illuminated by Tesla's polyphase alternating current system. The Westinghouse display was a historic collection of machines, all powered with Tesla/Westinghouse alternating current. Electricity, and AC current, was going to spread coast and coast and beyond. The “City of Light”, as it came to be dubbed, was powered by 12 thousand-horsepower AC polyphase generators. The fair showed how safe AC current could be. It was a spectacular display of lights and energy, which illuminated the exposition and it was said to be a beautiful sight to behold.


The Devil in the White City, by Erik Larson:


“If evenings at the fair were seductive, the nights were ravishing. The lamps that laced every building and walkway produced the most elaborate demonstration of electric illumination ever attempted and the first large-scale test of alternating current. The fair alone consumed three times as much electricity as the entire city of Chicago. These were important engineering milestones, but what visitors adored was the sheer beauty of seeing so many lights ignited in one place, at one time. Every building, including the Manufactures and Liberal Arts Building, was outlined in white bulbs. Giant searchlights — the largest ever made and said to be visible sixty miles away — had been mounted on the Manufactures’ roof and swept the grounds and surrounding neighborhoods. Large colored bulbs lit the hundred-foot plumes of water that burst from the MacMonnies Fountain.” … it “was like getting a sudden vision of Heaven.”


While the hydraulic tunnel was under construction, the development of the of polyphase apparatus justified the official decision of May 6, 1893, five years and five days after the issuing of Tesla's patents, to use his system since Westinghouse received a contract to set up the first long-range power network, with AC generators at Niagara Falls producing electricity for distribution in Buffalo, New York, 40 kilometers (25 miles) away. The Westinghouse Electric Company was subcontracted by the Cataract Company to build 5,000 horsepower (3,700 kW) 25 Hz AC generators, designed after the engineering and research work of Nikola Tesla and Benjamin Lamme for the Adams Station. This was a tremendous challenge since the earlier generators were only 150 horsepower. The turbines were to be installed into House No.3 by the I. P. Morris Company of Philadelphia, Pennsylvania based on a plan from the Swiss company of Faesch and Piccard.


The Chicago World's Fair in 1893 represented the success of the technological innovations with regard to alternating current and electrical apparatus developed by the Westinhouse company.


Col. Henry G. Prout wrote:


"The best result of the Columbian Exposition of 1893 was that it removed the last serious doubt of the usefulness to mankind of the polyphase alternating current. The conclusive demonstration at Niagara was yet to be made, but the World's Fair clinched the fact that it would be made, and so it marked an epoch in industrial history"


The exhibits included a switchboard, poly-phase generators, transformers, transmission line, step-down transformers, commercial size induction motors and synchronous motors, and rotary direct current converters (including an operational railway motor).


The Electricity Building - where Westinghouse's Exposition was located.
The Electricity Building - where Westinghouse's Exposition was located.
Westinhouse generator
Westinhouse generator
 The Great Allis-Corliss Engine
The Great Allis-Corliss Engine
Tesla's Polyphase Alternating Current 500 horse power generator, in Westinghouse Exposition.
Tesla's Polyphase Alternating Current 500 horse power generator, in Westinghouse Exposition.
 A Mammoth Dynamo
A Mammoth Dynamo


The Columbian Exposition, under a banner announcing the "Tesla Polyphase System", featured Nikola Tesla’s personal presentations with ( AC ) alternating current and several of his electromechanical devices which included his two phase induction motor and generators to power the alternating current system. Tesla demonstrated a series of electrical effects previously performed throughout America and Europe. This included using high-voltage, high-frequency alternating current to light a wireless gas-discharge lamp. 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 lamps 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 Tesla in London about two years previous, "where they produced so much wonder and astonishment"


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


The Inventions, Researches and Writings of Nikola Tesla- by Thomas Commerford Martin, Editor - PART IV: Early phase motors and the Tesla mechanical and electrical oscilations - Chapter XLII: Mr. Tesla's Personal Exhibit at the World's Fair:


[Pg 477]


While the exhibits of firms engaged in the manufacture of electrical apparatus of every description at the Chicago World's Fair, afforded the visitor ample opportunity for gaining an excellent knowledge of the state of the art, there were also numbers of exhibits which brought out in strong relief the work of the individual inventor, which lies at the foundation of much, if not all, industrial or mechanical achievement. Prominent among such personal exhibits was that of Mr. Tesla, whose apparatus occupied part of the space of the Westinghouse Company, in Electricity Building.


This apparatus represented the results of work and thought covering a period of ten years. It embraced a large number of different alternating motors and Mr. Tesla's earlier high frequency apparatus. The motor exhibit consisted of a variety of fields and armatures for two, three and multiphase circuits, and gave a fair idea of the gradual evolution of the fundamental idea of the rotating magnetic field. The high frequency exhibit included Mr. Tesla's earlier machines and disruptive discharge coils and high frequency transformers, which he used in his investigations and some of which are referred to in his papers printed in this volume.


Fig. 297 shows a view of part of the exhibits containing the motor apparatus. Among these is shown at A a large ring intended to exhibit the phenomena of the rotating magnetic field. The field produced was very powerful and exhibited striking effects, revolving copper balls and eggs and bodies of various shapes at considerable distances and at great speeds. This ring was wound for two-phase circuits, and the winding was so distributed that a practically uniform field was obtained. This ring was prepared for Mr. Tesla's exhibit by Mr. C. F. Scott, electrician of the Westinghouse Electric and Manufacturing Company.


[Pg 478]


Fig. 297. Nikola Tesla's personal exhibit at the World Fair in Chicago, 1893.
Fig. 297. Nikola Tesla's personal exhibit at the World Fair in Chicago, 1893.
Edison's presentation of Direct Current lighting (General electric Company)
Edison's presentation of Direct Current lighting (General electric Company)


The Westinghouse Company was asked to supply parts for the conversion of the waters of the Niagara Falls into electrical power. The plant erected for this purpose was the first to use units of such a great size to send electrical power out over distances.


The race was on between Morgan and Westinghouse to detemine who would control the future of electricity in America. Morgan didn't care what kind of electricity was used, as long as he was in control of it and he controlled Edison's DC patents. Westinghouse retained his faith that AC was the superior and more cost-effective system, and should be used for that reason, if no other.


During some years after the Columbian exposition the major application for electricity was the the direct current (DC) developed by Thomas Edison to light up the incandescent light bulbs, and the alternating current (AC) to light up the Westinhouse arc lights. Another company which produced products for electrical applications was the Thomson-Houston Company. The competition for the market was really agresive and the industrial development was dominated by demand of capital and commercial exploitation. For this reason the companies would have to ensure their survival and the consolidations were common. In 1892, financier J.P. Morgan engineered a merger between the Edison interests (the Edison General Electric Co.) and Thomson-Houston, (and others). The resulting company was named General Electric Co., one of the largest corporations of its time. Coffin became its president and Thomson stayed on as the new company's chief technical advisor.


Charles Coffin, proudly boasted of his tactics to gain ground for Morgan. He described raising the price of Edison-built streetlights from $6.00 to $8.00, specifically to raise an extra $2 per streetlight to pay off local politicians. He also advocated getting generators and distribution systems installed quickly, the advantage being that "the users willingly pay our price (for power in the future) as they cannot afford to change the system."


Westinghouse made it clear that he and Coffin did not share their style of doing business.


The House of Morgan therefore went after Westinghouse in a different manner, spreading rumors to Wall Street investors that Westinghouse's finances were unstable. Investors began to shy away from providing Westinghouse with new capital, capital being the lifeblood of his efforts to implement AC. This consolidation represented a challenge for the Westinhouse company, that needed to find more partners to ensure its solvency. Eventually it became clear that, if AC and the Westinghouse business were to survive, the remarkable royalty contract between Westinghouse and Tesla would have to be drastically altered.


This was the era of the Robber Barons, and one of the biggest was ready to make his move. J. P. Morgan, hoping to bring all U.S. hydroelectric power under his control, proceeded to manipulate stock market forces with the intention of starving out Westinghouse and buying the Tesla patents. Thanks in part to Tesla, this did not happen.


Westinghouse called on the inventor, pleading for an escape from the initial contract that gave Tesla generous royalties and he did it while stressing his commitment to AC power and Tesla's efforts. The inventor didn't offer any resistence to accept it but he even simply tore up the contract citing his friend's confidence and support.


Westinghouse came to Tesla and described the situation. Tesla replied with these words:


"Mr. Westinghouse, you have been my friend, you believed in me when others had no faith; you were brave enough to go ahead... when others lacked courage; you supported me when even your own engineers lacked vision... you have stood by me as a friend...


"Here is your contract, and here is my contract. I will tear both of them to pieces, and you will no longer have any troubles from my royalties. Is that sufficient?"


This generous gesture represented the flourishment of the Westinghouse Electric and Manufacturing Company. Accepting this situation would represent that the funding for his own further research and inventions would shrunk at least several million dollars in long terms.


He was, after all, grateful to the one man who had believed in his invention. And he was convinced that greater inventions lay ahead. The Westinghouse Electric Company was saved for future triumphs. Tesla, although sharing the glory, was left forever afterward in recurring financial difficulties.


 Power house nos 1 and 2 with the step up transformer house USA (American side). 1908
Power house nos 1 and 2 with the step up transformer house USA (American side). 1908


Tesla’s inventions and ideas resulted to be essential for the Niagara Falls project, however he was not the only inventor who was necessary and there were many others which applyed their efforts in the development of AC system and the first designs to be able to develop this colosal project.


It was important for the Niagara falls power project to create a team of formed and capable engineers to share their knowledge and their achivements to transform allthose ideas into a reality:


The water power engineer Thomas Evershed at 69 years old conducted the Erie Canal and it was his last major project. Electrical engineer Benjamin G. Lamme designed various generators, motors, rotary converters and other apparatus. He worked to improve Tesla’s generator designs which he constructed. Before Tesla, Lamme and Oliver B. Shallenberger Westinghouse had other engineers and contributors to investigate on AC electricity: the pioneer electrical inventor William Stanley Jr., Paul M. Lincoln, Lewis B. Stillwell and mechanical and electrical engineer Albert Schmid.


All these inventors and even more were involved in the beginning of the electrical age and they created the basis for the modern polyphase system to provide the electrical power services.


Shortly after arriving in the United States in 1893, Steinmetz went to work for Rudolf Eickemeyer in Yonkers, New York, and published in the field of magnetic hysteresis, which gave him world-wide professional recognition. Eickemeyer's firm developed transformers for use in the transmission of electrical power among many other mechanical and electrical devices. Eickemeyer wasn't much of a scientist, but he was very driven. Eickemeyer was erratic, he built hat-making machines, worked on dynamos. In 1893 with Stephen D. Field, and Steinmetz he invented a system of electric street cars but in 1893 Eickemeyer's company, along with all of its patents and designs, was bought by the newly formed General Electric Company, where he quickly became known as the engineering wizard in GE's engineering community.


Steinmetz was always far ahead of his colleagues in mathematical skills, and few in his lecture's audience understood the brilliance of his ideas about magnetism and alternating current circuits. In the groundbreaking paper, "Complex Quantities and Their Use in Electrical Engineering", presented at a July 1893 meeting published in the American Institute of Electrical Engineers (AIEE) he explained about hysteresis advancing studies begun by Nikola Tesla. His life's work was mostly comprised of expounding upon the work of Nikola Tesla. And Tesla also held the actual patent from 1889 on A.C. US413,353 - Method of Obtaining Direct from Alternating Currents - October 22, 1889.


The german engineer simplified these complicated methods to "a simple problem of algebra". He systematized the use of complex number phasor representation in electrical engineering education texts, whereby the lower-case letter "j" is used to designate the 90-degree rotation operator in AC system analysis. In 1897 he published the first book to reduce ac calculations to a science. He published his theories in articles and textbooks, including educational books to teach the mathematics required to understand his ideas. Steinmetz also originated standard symbolic notation for schematic drawings of ciruits. At General Electric Steinmetz staffed the company lab with bright, creative people working under his tutelage.


Stanley, working under the direction of Westinghouse on the Gaulard and Gibbs system on 1886, devised a further improvement, which consisted in securing the enclosure of the coils by making the core of E-shaped plates, the central projections of each successive plate being alternately inserted through rewound coils from opposite sides, thus permitting separate winding and consequently the better insulation of the coils. Albert Schmid improved Stanley's design a few years after the Columbian exposition, following by extending the ends of the arms of the E-shaped plates to meet at a central projection. When inserting these plates the extensions were temporarily bent upward, and upon being released each plate formed a closed magnetic circuit about the sides of the coils.


The first three-phase transformer was created by Mikhail Dolivo-Dobrovolsky in Germany, a short time after Schmid's improvement. However, Steinmetz once said:


"I really cannot see anything new in the new Dobrowolsky system"



On August 10, 1893 new bids were requested based on a design by Professor Forbes of the Cataract company for a 20,000 volt two-phase generator with an external rotating field of the “umbrella” type whereas a rotating armature was standard practice.


General Electric recommended and competed with a 3 phase bid ($1 million) designed by Steinmetz to get the power generation contract at Niagara. However, two-phase four-wire was selected because it was expected that much of the local load would be single-phase. Next the frequency had to be selected.


Tesla once discovered that the most efficient frequency for alternating current is 60 Hz. He did some great empirical work to determine that 220V AC at 60Hz was the optimal combination (at least for motors, which were the key to having an electricity business in the late 19th century) but Edison forced 110V AC on the US because that's what his DC generators on Pearl Street in NYC ran at. At higher frequencies than 60HZ AC motors would become inefficient and at lower frequencies than 60HZ it would be required too much iron and lights would also flicker. It was after World war II that European countries started following 220V 50Hz standard suggested by the AEG company.


Hydraulic turbines had been ordered with a speed of 250 rpm. The frequencies possible at 250 rpm were: 16 2/3-Hz with 8 poles on the rotating field; 25-Hz with 12 poles; 33 1/3-Hz with 16 poles and 41 2/3- Hz with 20 poles. Low frequencies were preferred for large motors and rotary converters. Professor Forbes preferred 16 2/3- Hz for the commutating type ac motors then in use. Higher frequencies were more suitable for incandescent and arc lights. Tests had shown that at 25 Hz incandescent lamps did not show objectionable flickering. Westinghouse had adopted 60 Hz for lighting and 30 Hz for power and refused to guarantee efficiency at less than 30 Hz. General Electric recommended 41 2/3 Hz. Following a dinner meeting in October in New York City with Westinghouse representatives, President Adams of the Cataract Company asked Westinghouse’s chief electrical engineer if they could build and guarantee a 25-Hz generator.


Edward Dean Adams:


"Formerly the various kinds of current required by different kinds of lamps and motors were generated locally; by the Niagara-Tesla system only one kind of current is generated, to be transmited to places of use and then changed to the desired form"


One of the two-phase generators of 5000 H.P. installed at the Adams Power Station. The generators were put into pilot operation, started on August 16, 1895 and commertial exploitation on April 26.
One of the two-phase generators of 5000 H.P. installed at the Adams Power Station. The generators were put into pilot operation, started on August 16, 1895 and commertial exploitation on April 26.


In 1894 the Niagara Falls Power Company began placing contracts for Edward Dean Adams power station #1.


Pelton Waterwheel Company furnished the five and one-half foot water turbines mounted 140 foot below the water inlet that provided about 145,000 gallons per minute. A "fly-ball" governor controlled the correct amount of water to maintain the speed of the vertical shaft.


Westinghouse furnished the 5000 horsepower (3,700 kW) generators that connected to the turbine. Twelve, 2800 pound, electromagnets plus the drive shaft provided a 25-ton flywheel that spun as an outer structure (umbrella type) around the windings that were arranged as two sets of poles at 180 degrees to produce two phase and 2,300 volts. Six poles rotating at 250 revolutions per minute produced 25- cycles. This output was connected by four wires to a control panel.


Amperes equals watts divided by volts so each phase was capable of carrying 826 amperes.


A portion of the power from each phase of the first generator was connected to two transformers that stepped the voltage down to 440 volts to operate a two-phase Tesla induction motordriving a DC generator that produced 585-volts to power the existing Niagara Falls trolley system.


 A Niagara generator under construction at Westinghouse in Pittsburgh 1894
A Niagara generator under construction at Westinghouse in Pittsburgh 1894


Baldwin, the locomotive manufacturer, and Westinghouse joined forces in 1895 to develop AC railway electrification.


In the early morning hours of March 13, 1895 a fire broke out and burned everything in the Tesla laboratory.


On April, 15th, 1895 the first Niagara Generator was tested which bore Tesla's name and patent numbers, it was run at full speed, 250 revolutions per minute, and proved quite satisfactory.


On August 25 or 26, 1895 the powerhouse #1 began producing power but Tesla did not attend the opening. At this time, there were only three generators set up of 5,000 horsepower (3,700 kW) each and 25 Hz, two-phase, four-wire generators, which produced 2,200 volts. The Niagara Falls project ushered in the second phase of the Industrial Revolution and shaped and determined the way power would be produced and delivered from then on.


The Power House #1 was completed on 1896 but The Adams Power buildings would see extended building expansion and equipment added continuously for the next 7 years.

A book written by the Westinghouse Company described the apparatus used in the Niagara Falls project as follows:


Power House No. 1 now contains ten generators of the outside revolving field, vertical shaft type. These ten generators are divided into banks of five each, and each bank has a separate switchboard. Current is generated at about 2,200 volts and a great deal of the service in and around Niagara Falls is served direct at this voltage. photograph of power house of the Manhattan Railway, New York For a part of the more distant Niagara Falls service, voltage is stepped up to 11,000, and for the Buffalo, Lockport, and Tonawanda service, voltage is stepped up to about 22,000. The development has been so rapid that the demands on the long distance service alone now take about two-thirds of the power developed by these first ten machines. It has been necessary, therefore, to build a new power house on the opposite bank of the canal for the large amount of local service which has to be rendered. (Works of the Westinghouse Electric & Manufacturing Company, 1904)


Adams power station during construction 1895
Adams power station during construction 1895


The Niagara Power Station No. 1, as it was then called, would eventually generate 50,000 horsepower (37 MW) of electricity. There were 10 generator rated 5,000 horsepower (3,700 kW) of the outside revolving field, vertical shaft type. The generators were separated into two banks of five generators each with independent switchboards. The output was at 2,000 volts to server in and around Niagara Falls. There were transformers to step up the voltage to 10,000 volts to serve the medium distance around Niagara Falls areas. The voltage was also stepped up to 20,000 to serve the longer distance for Buffalo, Lockport, and Tonawanda. The station was the model for a second similar station built in 1904. The entire plant was officially named after Edward Dean Adams in 1927.


The Niagara Falls Power Company supplied alternating current through the use of the ten Westinghouse AC generators of 5,000 h.p. capacity with 430 cubic feet of water turning the turbines at 250 rpm. This was the capacity of NFPC Power House No. 1.


Interior Power House No 1. Generating station of the Niagara Falls power company, showing the ten 5,000 H.P. Generators (American side)
Interior Power House No 1. Generating station of the Niagara Falls power company, showing the ten 5,000 H.P. Generators (American side)
 Interior of Edward Dean Adams power station at Niagara, with ten 5,000-horsepower Tesla/Westinghouse AC generator.
Interior of Edward Dean Adams power station at Niagara, with ten 5,000-horsepower Tesla/Westinghouse AC generator.




The experience gained with the use of two-phase power at the Colombian Exposition may have had some influence on the decision by Westinghouse to employ a 2 phase generator design for the first ac powerhouse at Niagara Falls, which went into operation in 1895. The generators used at Niagara Falls were of a more conventional design, being single machines having two interleaved windings rather than two distinct machines coupled together. These generators operated at a frequency of 25 cycles (25 Hz) since it was expected that a significant portion of the power produced would be used to operate rotary converters so as to obtain direct current (dc) for industrial uses such as aluminum production. These early rotary converters required a low frequency for satisfactory operation. 


There was obviously still a mistrust of the practicality of 3 phase power throughout the electric power industry at that time. For example, according to an article from 1896 titled "Present Status of the Transmission and Distribution of Electrical Energy" in the AIEE Transactions: 


Where a two-phase transmission with separate circuits is used, then if the separate circuits are wound on different armatures, each can be regulated to give a constant voltage at the receiving end. This is the case, for instance, in the large dynamos built by the Westinghouse Company for use at the World's Fair in Chicago. The difficulty due to the uneven loading of the circuits is specially marked in the case of the three-phase system, and it is one of the principal objections that have been urged against the employment of this system for purposes of distribution. 


It had already been realized, however, that the 3 phase configuration was superior for transmission from the point of view of efficiency. Thus, special phase-changing transformers were designed by Charles F. Scott of Westinghouse in order to step up the 2 phase generated voltage at Niagara Falls to 11,000-V, three-phase for transmission to Buffalo, New York. The General Electric Company was awarded the contract to build the phase-changing transformers and so was licensed by Westinghouse to utilize the connection developed by Scott for this purpose. 


Charles F. Scott:


"The evolution of electric power from the discovery of Faraday to the initial great installation of the Tesla polyphase system in 1896 is undoubtedly the most tremendous event in all engineering history".


A Scott-T transformer (also called a Scott connection) is a type of circuit used to derive two-phase electric power (2-φ, 90-degree phase rotation) from a three-phase (3-φ, 120-degree phase rotation) source, or vice versa. The Scott connection evenly distributes a balanced load between the phases of the source. The Scott three-phase transformer was invented to bypass Thomas Edison's more expensive rotary converter and thereby permit two-phase generator plants to drive Nikola Tesla's three-phase motors.


At Buffalo, some of this 3 phase power was used for rotary converters that supplied 110/220-V dc power for the Edison distribution system downtown. However, some of the received power was converted back into two-phase power for general lighting purposes in outlying areas. Motor- generator sets were used for this latter conversion because the frequency of the ac power was increased as well in order to avoid undesirable flickering of incandescent lamps. The frequency used was actually 62.5 cycles, rather than 60 cycles, so as to simplify the design of these frequency changers. The conversion back to 2 phase power was motivated by the conviction, at that time, that satisfactory voltage regulation was more easily achieved in the two separate phases of a two-phase system than in a 3 phase system. 


This belief in the superiority of 2 phase systems with respect to voltage regulation led to the extended use of two-phase distribution in many locales. For example, in Cohoes, New York, (north of Albany) a 1915 hydroelectric station was designed to generate three-phase power. However, some of that power was converted to 2 phase using "Scott" type transformers in order to supply an extensive network of existing two-phase feeders for lighting, rather than change those feeders to 3 phase operation.


Power house 1
Power house 1


The Niagara Falls Power Co. distribution system in 1897. The local Niagara Falls load was supplied 2200 V by two-phase four-wire or single phase two-wire and consisted of a mixture of ac and dc applications plus motors and lighting. The Buffalo electric trolley load was less than 2,000 hp.



Diagram of General Scheme of Power Distribution.
Diagram of General Scheme of Power Distribution.


The transformer house building was designed by the architectural firm of McKim, Mead, and White. Locally quarried limestone was used in its construction. The transformer house was "built on the upper river, above deep excavations housing twenty-one generating units. Tailwater from the generators passed into a 7000-ft tailrace tunnel, which conveyed the water beneath the city to the lower river, near the present-day site of the Rainbow Bridge. The 18-ft by 21-ft tunnel required over 3 years to build, used more than 16 million bricks in a four-course lining. It also cost the lives of twenty-eight workers."

 Step up transformer plant of the Niagara Power Company Canada. 1908
Step up transformer plant of the Niagara Power Company Canada. 1908
11,000-volt Switchboards and Bars in "Step up" transformers of the Niagara Power Company Canada. 1908
11,000-volt Switchboards and Bars in "Step up" transformers of the Niagara Power Company Canada. 1908


By 1896, Thomas Evershed developed a plan to use massive underground tunnels and a powerhouse to capture the power of the Niagara River at the falls. With financing from moguls like J.P. Morgan, John Jacob Astor IV, and the Vanderbilts, they had constructed giant underground conduits leading to turbines generating upwards of 100,000 horsepower (75 MW), and were sending power as far as Buffalo, 20 miles (32 km) away. Some of the original designs for the power transmission plants were created by the Swiss firm Faesch & Piccard, which also constructed the original 5,000 horsepower (3,700 kW) waterwheels.


In 1896 Tesla still had not come to Niagara beeing obsessed with his wireless experiments but Westinhouse invited him and he accepted. On July 19 Nikola Tesla visited the Niagara Falls Power Company's Power House with George Westinhouse and others. Westinhouse sent his Pullman car to bring Tesla to Pittsburgh plant first. Tesla was entretained at Solitude by Westinhouse and Marguerite, who had been allways close to Tesla. Westinhouse was able to get caught up on the wireless, X-ray and radio experiments. They also spent a day in East Pittsburgh Works and they had launch with some old friends such as Benjamin Lamme and Charles Scott (Scott had been Tesla's assistant in 1888 at the Garrison Alley Plant).


The next a Gazette reporter, who spoke with Mr. Tesla described the inventor:


"It is a difficult thing to interview Nikola Tesla, but to sit down and talk with him, man to man, is a privilege to be enjoyed and remembered. One seldom meets a man more free from affectations and self-consciousness. He does not like to talk about himself and when the subject comes up he is sure to steer away from it as soon as possible..."


The reporter continued:


"Tesla is an idealist, and anyone who has created an ideal of him from the fame that he has won will not be disappointed in seeing him for the first time. He is fully six feet tall, very dark of complexion, nervous, and wiry. Impressionable maidens would fall in love with him at first sight, but he has no time to think of impressionable maidens. In fact, he has given as his opinion that inventors should never marry. Day and night he is working away at some deep problems that fascinate him, and anyone that talks with him for only a few minutes will get the impression that science is his only mistress, and that he cares more for her than for money and fame.


He had one of his rare moments yesterday when he could be induced to talk of science, and when asked of the advances made in the problem of transmission, with earnest face and eyes fairly ablaze, he said, "There is no obstacle in the way of the successful transmission of power from the big power house you have here. The problem has been solved. Power can be transmitted to Buffalo as soon as the Power Company is ready to do it."


As the famous electrician grew enthusiastic he gestured with his hands which are apparently trustworthy indicators of his nervous condition. They trembled a little as he held them up and the conclusion to be drawn from them was that their possessor was a man of tremendous nervous energy...


He said:


"I am just off a sick bed, and am not very strong yet. Yes, this is my first visit to Niagara Falls and to the power house here. Oh, it is wonderful beyond comparison; those dynamos are the largest in the world. It always effects me to see such things. The shock is severe upon me..."


The Niagara Falls Hydraulic Power and Manufacturing Company's Station No. 2 puts its first four generating units into operation on November of 1896.


Static Transformers at Niagara End of Buffalo Transmissio Line. 200 Volts 2 Phase to 11,000 Volts 3 Phase
Static Transformers at Niagara End of Buffalo Transmissio Line. 200 Volts 2 Phase to 11,000 Volts 3 Phase


On November 16, 1896 the Niagara Falls Power Company transmits alternating current to Buffalo and other areas via lines owned by the Cataract Power and Conduit Company, and the project became world famous. From there, the electricity was distributed to consumers, the largest of which were the International Railroad Company and the Buffalo General Electric Company. Step-up transformers, allowed for the transmission of that power and the power station were sending power as far as 22 miles (32 km) away, and 1,000 horsepower were switched at exactly midnight with a signaling of the event to the city by the firing of cannons, the blowing of steam whistles and the ringing of bells. The Niagara Falls line can deliver an output power up to 750 kW at voltages up to 11 kV. So much power had never before been transmitted over a long distance from a central power station.


In Buffalo, New York's Ellicott Club hosts a "Power Banquet" on January 12, 1897 and the guest Nikola Tesla offered an speech which was a prediction of the great future for the Niagara Frontier.


On Electricity - Commemoration of the introduction of Niagara Falls power in Buffalo, New York, at the Ellicott Club -  Electrical Review - January 27, 1897:


"We have many a monument of past ages; we have the palaces and pyramids, the temples of the Greek and the cathedrals of Christendom.  In them is exemplified the power of men, the greatness of nations, the love of art and religious devotion.  But the monument at Niagara has something of its own, more in accord with our present thoughts and tendencies.  It is a monument worthy of our scientific age, a true monument of enlightenment and of peace.  It signifies the subjugation of natural forces to the service of man, the discontinuance of barbarous methods, the relieving of millions from want and suffering"


Two-Phase transformers.
Two-Phase transformers.


Charles F. Scott:


"The evolution of electric power from the discovery of Faraday to the initial great installation of the Tesla polyphase system in 1896 is undoubtedly the most tremendous event in all engineering history".


 The ‘Tee’ connection of the two high voltage windings gives three phase
The ‘Tee’ connection of the two high voltage windings gives three phase


Two single-phase air-cooled or ‘air blast’ 930-kW transformers were installed at Niagara. They were Scott connected from 2-phase 4-wire 2200-V to 3-phase 3-wire 11,000-V.

These transformers have a primary voltage rating of 21 or 22,000 V, but the rating of an old lightning arrester in the corner of the main electrical room indicates that the incoming high voltage ac line operated at a voltage of no more than about 11,000 V. If these transformers were connected to this line in a wye-connection, their secondary voltage would have been close to the 110 V required for lighting purposes.

 The eight of ten 1,875 kW transformers at the Adams Power Plant Transformer House, the first large-scale, alternating current electric generating plant in the world, built in 1895
The eight of ten 1,875 kW transformers at the Adams Power Plant Transformer House, the first large-scale, alternating current electric generating plant in the world, built in 1895
Transformer plant of the Niagara Power Company Canada. 1908
Transformer plant of the Niagara Power Company Canada. 1908
Longitudinal and Transverse Views of Power Houses, showing wheelpits, generators, shafts, turbines, penstocks and discharge tunnels.
Longitudinal and Transverse Views of Power Houses, showing wheelpits, generators, shafts, turbines, penstocks and discharge tunnels.


Transverse Section of Power House No. 2. Niagara Falls Power Company Source: The Niagara Falls Electrical Handbook: Being a Guide for Visitors from Abroad Attending the International Electrical Congress, St. Louis, Mo., September, 1904. Niagara Falls, N. Y. : Pub. under the auspices of the American Institute of Electrical Engineers, 1904. p. 73.




On 1899 the British Westinghouse Electric and Manufacturing Company was founded.


The Cataract Construction Company goes into liquidation on January 1, 1900, having completed its construction contracts for the Niagara Falls Power Company February 12, 1900. Also the ground is broken for the extension of the power tunnel to the newly begun Niagara Falls Power Co.'s Power House No. 2


In the year 1901 Westinhouse acquires Bryant Electric Company of Bridgeport, Connecticut, which continues operation as a subsidiary. By the same year the city of Buffalo, New York hosted the Pan American Exposition. The Expo served both the United States government as a place for welcoming Central American countries after the recent Spanish American war and it gave the City of Buffalo and New York State a platform to advertise their new science and technology in the production of hydro-electric power. The opening festivals included a speech by Theodor Roosevelt who was at that moment in time, the Vice President of the United States.


By that time, the electric power development of Niagara Falls had become quite extensive, and a presentation on this topic was given by Philip Barton, a representative of the Niagara Falls Power Company.


The entire Pan-American Exposition was powered by the electricity produced by only one of those ten generators from the power house nº1. While a second power station would eventually be constructed across the canal, it was Power House No. 1 that produced most of the AC in the Western New York region at the time of the Exposition.


By 1901, the city had electric street lights an electric trolly system and was lighting a few of their large public buildings. Buffalo was a growing sprawl of urban development with key industries in Grain and Flower, Steele production and many forms of manufacturing. In conjunction with the famous Erie Barge Canal and having a great train station it had become a major shipping center between Chicago and the great mid-western wheat-belt and Atlantic shoreline cities such as New York, Boston and Baltimore.


Barton’s presentation included an elaborate schematic drawing showing in detail all of the various electrical loads supplied by power generated at Niagara Falls. A majority of these loads used dc supplied by rotary converters.


In that era, it was common practice to define the capacities of electrical machinery in terms of horsepower (hp), rather than kilowatts (kW), with 1 hp being equivalent to 0.746 kW. Barton’s schematic indicates that a total of 5,000 hp (3,700 kW) in rotary converters were installed at the Pittsburgh Reduction Company in Niagara Falls for the production of aluminum (this company later became Alcoa).


The Exposition was sometimes called "The Rainbow City" because of the way strings of lights covered the many buildings of various colors. A central focus was made on the massive " Electric Tower " which was designed by John Galen Howard. This tower measured 391 feet tall and acted as a great light beacon. It functioned as a place to view not just the Exposition itself, but also the great "Niagara River" in the distance.


Also, locally in Niagara Falls, three chemical companies used a total of 3,000 hp in rotary converters to supply dc for electrolysis processes that produced chemicals such as potash (potassium hydroxide), sodium, and caustic soda (sodium hydroxide).


The Natural Food Company used a total of 2,500 hp in rotary converters in its factory that produced its famous shredded wheat breakfast cereal. Perhaps adjustable speed dc motors were needed for mixers or for conveyors through continuously fed ovens.


The ac from the Westinghouse generators at Niagara Falls was stepped up to 22,000 V and sent to the city of Buffalo, a distance of about 25 mi (40.2 km). There, rotary converters were used to supply dc for the operation of street railways. The same was true in the nearby towns of Lockport and Tonawanda, as well as on the Canadian side of the Niagara River. The total streetcar load fed by rotary converters at all locations was nearly 10,000 hp (about 7.5 MW), which included a streetcar line in the Niagara River gorge itself.


In addition, the Lockport Gas and Electric Company used a rotary converter to supply the Edison dc distribution for lighting. In Buffalo, however, a conventional motor-generator set was used for this purpose.


Eventually, the rotary converter exciters at the Niagara Falls power station were fitted with Lamme’s amortisseur windings and, so, became usable. Also, a 500-hp rotary converter from the 1893 Chicago Exposition was installed in this power station, presumably to supply dc for the local streetcar line.


From 1904-05  Baldwin-Westinghouse (electric locomotives and A.C. electrification of railroads) supplied locomotives carrying a joint builder's plate to a number of American railroads, particularly for the New Haven (the New York, New Haven and Hartford Railroad) line from New York to New Haven, and other New Haven lines.


The fundamental Tesla patents granted on May 1888 expired on May 4, 1905 and became public property.


Private companies on the Canadian side also began to harness the energy of the falls. The Government of the province of Ontario, Canada eventually brought power transmission operations under public control in 1906, distributing Niagara's energy to various parts of the Canadian province.


"Tesla split-phase patents" US511,559 - Electrical Transmission of Power - December 26, 1893 & US511,560 - System of Electrical Power Transmission - December 26, 1893 (both issued on September 26, 1893) expired on December 26, 1910.


Other hydropower plants were also being built along the Niagara River. But in 1956, disaster struck when the region's largest hydropower station was partially destroyed in a landslide. The landslide drastically reduced power production and tens of thousands of manufacturing jobs were at stake. In 1957, Congress passed the Niagara Redevelopment Act, which granted the New York Power Authority the right to fully develop the United States' share of the Niagara River's hydroelectric potential.


In 1961, when the Niagara Falls hydroelectric project first went on line, it was the largest hydropower facility in the Western world. Today, Niagara is still the largest electricity producer in New York State, with a generating capacity of 2.4 gigawatts. Up to 375,000 U.S. gallons (1,420 m3) of water a second is diverted from the Niagara River through conduits under the City of Niagara Falls to the Lewiston and Robert Moses power plants. Currently between 50% and 75% of the Niagara River's flow is diverted via four huge tunnels that arise far upstream from the waterfalls. The water then passes through hydroelectric turbines that supply power to nearby areas of Canada and the United States before returning to the river well past the falls. This water spins turbines that power generators, converting mechanical energy into electrical energy. When electricity demand is low, the Lewiston units can operate as pumps to transport water from the lower bay back up to the plant's reservoir, allowing this water to be used again during the daytime when electricity use peaks. During peak electrical demand, the same Lewiston pumps are reversed and actually become generators, similar to those at the Moses plant.



On the Canadian side of the Niagara River are three great power plants which are now generating about 160,000 horse-power, but which will ultimately develop nearly 400,000 horse-power. The Canadian generators are of much greater capacity than those on the American side and develop from' 10,000 to 12,500 horse-power each. Two of these plants are built over wheelpits like those described on the American side and one of the companies in order to release the water used in its turbines has constructed under the Niagara River a tail race tunnel, the portal of which discharges directly beneath the Horse Shoe Falls.


Cross-Section Assembly of 10,000 H.P., 10,000 Volt Generator Building for Canadian Niagara Falls Power Co.
Cross-Section Assembly of 10,000 H.P., 10,000 Volt Generator Building for Canadian Niagara Falls Power Co.
A 1953 photo of the original Westinghouse generators at the Niagara Falls power plant. From the Kenneth Swezey Papers in the Archives Center of the American History Museum.
A 1953 photo of the original Westinghouse generators at the Niagara Falls power plant. From the Kenneth Swezey Papers in the Archives Center of the American History Museum.
Nikola Tesla monument installed at Goat Island, Niagara Falls, a gift to the United States on the occasion of its bicentennial and Tesla's 120th anniversary, July 23, 1976. The monument is a second casting of the sculpture by Fran Krsinic.
Nikola Tesla monument installed at Goat Island, Niagara Falls, a gift to the United States on the occasion of its bicentennial and Tesla's 120th anniversary, July 23, 1976. The monument is a second casting of the sculpture by Fran Krsinic.




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Write a comment

Comments: 3
  • #1

    Paakofi Sinatra (Thursday, 13 December 2018 11:46)

    This man demonstrated just a fraction of what he was willing to uncover. The impact has so far been monumental in the past century. We can now only imagine where we would have been with Tesla still alive today.

  • #2

    Jim Missall (Sunday, 22 September 2019 22:27)

    This is an incredible expose on Pioneering AC power generation and I appreciate all the research done in providing the information.

    I wish to preserve the Adams Transformer House at Niagara Falls converting this landmark heritage site from a present day vacant warehouse to world destination museum.

    If you would be interested in getting involved please contact me

  • #3

    Miles Kilometres (Thursday, 09 January 2020 17:24)

    I like it