How Nikola Tesla Worked

Tesla's father was an Orthodox priest who wanted his son, born in 1856, to be the same. Ethnic Serbs, the Tesla family lived in Croatia, then part of the Austro-Hungarian empire. Nikola's mother invented household appliances like an eggbeater, and the boy felt that he took after her. When he became ill as a teenager, he made his father promise to send him to technical school if he recovered. Hoping to become an engineer, he studied mechanics and electricity at Austrian Polytechnic School in Graz, Austria [source: Vujovic].

As a boy, Nikola had seen a picture of Niagara Falls. He instantly envisioned a giant millwheel that would harness the power of the cataract. Such visions pointed to the unique nature of Tesla's mind. The young man could solve calculus problems in his head and possessed a photographic memory. But it was his powers of visualization that were most remarkable: Ideas appeared to him fully formed, almost as hallucinations.

But his brilliance had a down side. In his 20s, the tall, rail-thin Tesla endured a nervous breakdown that made him hypersensitive -- the sound of a ticking watch tormented him and he found sunlight oppressive. Throughout his life, he suffered from phobias and compulsions.

Tesla took an early interest in alternating current (AC). At the time, experiments with motors and lighting used direct current (DC), like the current that flows from a battery. DC motors were inefficient, but no one could imagine how an AC motor would work. One day, while walking in a park discussing poetry, Tesla had a sudden insight about how to make an AC motor a reality.

His idea for using alternating current baffled experts in Europe. In 1884, the 28-year-old Tesla decided to travel to New York and present his ideas to Thomas Edison. He described his notions about AC to the great inventor, but Edison wasn't interested. Instead, he hired Tesla to work on his direct current equipment. The two men didn't hit it off -- Tesla quit after Edison failed to pay him for completing a job.

With no money, Tesla went to work digging ditches to earn a living. But his fortunes were about to turn.

Edison had signed up electricity subscribers for his DC system, stringing wires along the streets of New York City and wiring their homes. But George Westinghouse was already working on a competing AC system. He saw that Tesla's inventions could give him a big edge over Edison.

Tesla understood that AC was a more efficient way to drive motors and power lighting. Even more important, AC could be "stepped up" using coils of wires. Through induction, low voltage in one coil was transformed to high voltage in another. High voltage current could travel through wires more efficiently, then be stepped down for household use. Tesla's circuits were the forerunners of the transformers we routinely see on electric poles. Direct current could not be stepped up. To transmit it more than a few miles required ever thicker wires.

AC was known before Tesla began his work. But the inventor devised an integrated system of generators, transmission lines, motors, lighting and other circuitry that made AC a feasible alternative to DC. In 1887, Tesla filed for seven patents related to his AC inventions. They were awarded without being successfully challenged. Westinghouse bought the rights to them in 1888.

DC wasn't dead -- yet. Westinghouse and Edison plunged into what was known as the "War of the Currents." Going on the offensive, Edison claimed that AC was far too dangerous to be used by the public. His point was reinforced when an acquaintance of Edison's named Harold Brown arranged to have a Westinghouse AC generator provide the current for the execution of a condemned criminal in 1890 [source: PBS].

But Westinghouse, armed with the Tesla patents, could show that AC was a far more efficient alternative. The climactic battle in the War of the Currents took place at the colossal Chicago Columbian Exposition of 1893-94. Westinghouse was able to supply power for much less than what Edison would have charged. He won the contract and wired the fair based on the Tesla system. As the exposition opened, thousands of bright lamps flashed on, startling fair-goers. The demonstration dispelled public fears of alternating current, and AC became the standard for power systems.

The victory was hammered home by Tesla's realization of his childhood dream: a power generating plant at Niagara Falls. In 1890, investors took a big gamble on AC current and hydroelectric power, both still-unproven technologies. A long, tense wait ended in 1896 when the generators designed by Tesla began to feed power into the system. Eventually, they sent electricity all the way to New York City, lighting up Broadway. As hydroelectric plants began to be built around the world, the age of electrical power had arrived.

The war of the currents was over, but Nikola Tesla had already moved on to even more visionary inventions.

Even a simple electric current generates a magnetic field. An alternating current oscillating at a high voltage produces electromagnetic waves. Many inventors joined the race to make use of these waves, discovered by Heinrich Hertz in 1888, for wireless communication or other purposes.

Tesla was fascinated by high-frequency waves. Putting them to work, he was able to:

Many inventors contributed to the development of radio, but Guglielmo Marconi was awarded the Nobel Prize for the invention in 1909. Tesla resented the lack of recognition for his own fundamental and original contributions, which he had patented well before Marconi's first prototypes. In 1943, several months after Tesla's death, the U.S. Supreme Court finally recognized that Tesla's patented inventions were the basis of Marconi's initial achievement [source: PBS].

Tesla saw another use for the waves. He thought they would allow him to transmit electrical energy on a large scale without wires. He moved to Colorado Springs in 1898 and built large coils, now known as Tesla coils, which generated massive voltages. With them, he was able to generate man-made lightning. He lit 200 bulbs from a distance of 25 miles (40 km) and experimented with ways to send energy through the air or earth [source: Redshaw].

Returning to New York a year later, he convinced the banker J.P. Morgan to back him in a system that would create wireless communication around the world, allowing the broadcast of news, mail, even pictures. Tesla also continued to dream of transmitting electric power. He built a laboratory called Wardenclyffe on Long Island. There, he constructed a 187-foot-high (57-meters-high) wooden tower and drove steel pipes hundreds of feet into ground. As expenses mounted, Morgan backed out of the project. Deeply in debt, Tesla was forced to destroy the tower and abandon the laboratory in 1905. For the rest of his life, he remained convinced that wireless power transmission was feasible.

In the meantime, Tesla had used the electromagnetic waves to create a radio-controlled boat. He found that at very high voltages his homemade vacuum tubes gave off rays that could penetrate solid matter, and he was among the first to experiment with X-rays, creating what he called "shadowgraphs" [sources: Vujovic, Hrabak et al.]. Over time, Tesla's investigation of high-frequency waves formed the basis of innovations ranging from microwave ovens to cathode ray television picture tubes.

Tesla had taken his inventive genius in a different direction than contemporaries like Edison. His exploration of the unknown territory of high-frequency electricity and radio waves forged a path for many inventors who followed him.

Always eccentric, Tesla is now thought to have suffered from obsessive-compulsive disorder. As he aged, his quirks became more obvious. He had a phobia of germs and washed his hands obsessively. He would eat only boiled food. He was obsessed with the number three. He claimed he had received messages from outer space. As an old man, he became devoted to pigeons, which he smuggled into his hotel room.

Back in 1891, George Westinghouse's company had been on the verge of bankruptcy. To help the man who had put faith in him, Tesla agreed to give up the royalties he was owed on his AC patents. The inventor could have made millions, but was instead left destitute. Westinghouse died in 1914, never having fully compensated Tesla for his contributions.

Yet Tesla continued to invent. He was granted at least 275 patents in his lifetime [source: Twenty First Century Books]. He left behind him a long list of innovations, many of which he was never able to pursue:

Not all of Tesla's ideas worked. His dream of wireless power transmission never proved feasible. He dismissed Einstein's work, which would form the basis of modern physics. During and after World War I, Tesla worked on a "death beam," but it was never realized outside of science fiction movies [source: PBS].

In 1943, Tesla died alone and broke in a New York City hotel. He was 86. After his death, many of his papers disappeared. World War II was on; some speculated the FBI had seized them for possible military use. His possessions were later returned to Yugoslavia, but were his papers complete? Did others develop his ideas in secret? Conspiracy theories abound to this day.

"Some day," Tesla predicted in 1915, "there will be, say, six great wireless telephone stations in the world system connecting all the inhabitants of the earth to one another, not only by voice but by sight" [source: Cheney]. Sound familiar? Is that your cell phone or mine?