Tesla, Nikola (1856–1943)

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TESLA, NIKOLA (1856–1943)

Nikola Tesla was born in 1856 in Smilja, Croatia, to parents of Serbian heritage. The region of his birth was at the time part of the Austro-Hungarian Empire. His scientific and engineering aptitude were obvious at an early age, evidenced by stories of inventions consisting of simple mechanical devices he worked on during his childhood. For this reason his parents were persuaded to allow him to pursue an education in engineering rather than becoming a Serbian Orthodox priest as they had hoped. While Tesla studied at Graz Polytechnic and at the University of Prague, he developed an interest in electrical power transmission.

Moving into the commercial world, he accepted a position with a new telephone company in Budapest, where he developed a telephone repeater system, which formed the basis for the modern loudspeaker. Tesla was promoted within the company to a position in Paris. His potential was now clear to the manager of the plant, who recommended that he move to the United States to work with Thomas Edison, then considered the premier engineering genius of the age.

Tesla arrived in New York in 1884 and was hired by Edison. Edison understood Tesla's ability but remained unconvinced by his new employee's insistence on the use of alternating current for electrical power transmission. Nevertheless, Tesla accepted his assignment to work on improving Edison's direct-current method, which was then in use. Working long hours Tesla increased the system output and asked Edison for a $50,000 bonus, which Tesla understood he was to receive. Edison refused, claiming that the bonus had only been a joke. Tesla quit Edison's employ, and thereafter relations were strained between the two men.

Tesla was awarded patents on the alternating-current motor. In the single-phase AC motor, two circuits passing current are set up diagonally opposite with respect to a circular armature. With the currents ninety degrees out of phase, the armature rotates. In the polyphase AC motor, three or more circuits, each having a different phase separation, are employed. George Westinghouse, Jr., is reported to have bought all of Tesla's related patents for $1 million plus royalties, although the exact amount remains in dispute. The two men collaborated very close by. At the World's Colombian Exposition in Chicago in 1893, Tesla's system of alternating-current power transmission was successfully employed. The Westinghouse Company later won the contract to harness the hydroelectric power of Niagara Falls, producing a viable, long-distance, electrical distribution system. When financial difficulties beset the Westinghouse Company between 1891 and 1893, Tesla agreed to give up the royalties to which he was entitled.

Tesla now devoted his energies to work in his own laboratory in New York City. His inventions were numerous. He experimented with the transmission of signals using electromagnetic waves at the same time as Marconi was developing radio. At Madison Square Garden Tesla demonstrated remote control of mechanical objects. His Tesla Coil was capable of generating extremely high voltages. It consisted of three circuits. AC power was applied to the first circuit and, by means of transformers, the voltage was stepped up in the second and third circuits, both of which possessed spark gaps. The third circuit also included a capacitor tunable for resonance, thus allowing extremely large voltages to be developed.

In 1891 Tesla became a U.S. citizen. His naturalization papers remained among his most prized possessions.

Tesla accepted an offer of land and free electricity in Colorado Springs by the local electrical company to continue his research. In 1899, he conducted experiments he considered to be of extreme importance in the conduction of electricity through the earth without the use of wires. He reported that he was able, by means of this principle, to illuminate electric light-bulbs twenty-six miles from the power source. This transmission mechanism, which Tesla explained as taking place by means of the resonant frequency of the earth, has yet to be adequately verified to the satisfaction of the scientific community. In his Colorado Springs laboratory Tesla also performed experiments to simulate lightning that were successful enough to produce a power outage and along with it a withdrawal of the local company's offer of free electricity.

Tesla left Colorado Springs in 1900 and continued his research in a new laboratory on Long Island, which was opened in 1901. However, his efforts were beset by difficulties, not least of which were financial problems, which caused closure of this facility.

His flow of innovative ideas continued unabated. These included improvements for turbines, methods for communication with life on other worlds; and an idea characterized by the press as a "death ray," which may be interpreted as a precursor to the modern laser.

In 1915 it was falsely reported that Edison and Tesla had been jointly awarded the Nobel Prize in physics and that Tesla refused the honor because of his differences with Edison. The circumstances surrounding this news remain cloudy. Nevertheless, Tesla deeply felt the hurt of not receiving this recognition. In 1917 he was persuaded to accept the Edison Medal from the American Institute of Electrical Engineers as an acknowledgment of his pioneering contributions. Among the many honors bestowed on Tesla, perhaps the most important was having an electrical unit named after him, the tesla being the unit for magnetic flux density.

Toward the end of Tesla's life, unflattering articles were written about him, and there were innuendoes that he was involved in the occult. Money problems were never far away, and he moved his residence from one hotel to another, each one cheaper than the one before. His circle of friends contracted. Feeding the pigeons that lived close to his hotel became very important to him, and he developed an almost spiritual bond with them.

Tesla died in 1943. His funeral service was held in the Cathedral of St. John the Divine. As during his lifetime, controversy was not far away. The Serb and Croat mourners sat on opposite sides of the cathedral.

Tesla remains a fascinating man because of his personal life and his engineering genius. However, from a technical point of view Tesla is most remembered for his contributions to the use of alternating-current power transmission.

James D. Allan