The Human Side of Science: Edison and Tesla, Watson and Crick, and Other Personal Stories behind Science's Big Ideas (2016)

Chapter 7: Westinghouse and Tesla versus Edison—AC/DC Titans Clash

If Edison had a needle to find in a haystack, he would proceed at once with the diligence of a bee to examine straw after straw until he found the object of his search…I was a sorry witness of such doings, knowing that a little theory and calculation would have saved him ninety percent of his labor.

—Nikola Tesla1

Genius is one percent inspiration and ninety-nine percent perspiration.

—Thomas Alva Edison2

Tesla has contributed more to electrical science than any man of his time.

—Lord Kelvin3

America in the 1880s resembled a giant, recently awakened and just beginning to flex some muscle. There were big-time entrepreneurs in railroads, banking, steel, coal, oil, and many other developing industries, and there were constant struggles for their control. The conflict we're about to discuss had a lot of industrial overtones, but its roots were in the scientific world.

Let's start with a look at some of the participants, each of whom came from humble origins but whose egos had grown to be huge by the time the clashes took place.


Thomas Alva Edison (1847–1931) was born in Milan, Ohio, and was the seventh and last child of Samuel Edison and Nancy Matthews Elliott Edison. In 1854, the Edisons moved to Port Huron, Michigan, where they hoped the lumber business would be better than it was in Ohio. Shortly after the move, young Alva (as he was called) contracted scarlet fever, which delayed his entry into formal schooling and possibly left him with hearing loss. At age eight, when he finally got to school, he came home crying after three months, saying his teacher had referred to him as “addled.” His mother withdrew him immediately and took on the task of his education. She encouraged his independent thinking, which flowered under her guidance. Edison worked his way through many classics, including Newton's Principia, with the help of a family friend. He acquired a distaste for mathematics, saying he thought Newton could have appealed to a wider audience if he used less math. He loved to tinker.


Thomas Alva Edison (1847–1931). Used with permission from Sidney Harris.

In 1859, the Grand Trunk Railroad completed a rail line that included a run from Port Huron to Detroit. Edison worked on the train, selling Port Huron farm produce while on the way to Detroit, and Detroit newspapers on the way back. Edison's railroad career was quite successful. He was even allowed to use a spare freight car as a laboratory for his personal experiments. He also printed a newspaper of his own design, the Grand Trunk Herald. A chemical fire in the railway car laboratory, however, got Edison kicked off the train. While still working for the railroad, Edison saved three-year-old Jimmie MacKenzie from being hit by a runaway boxcar. Jimmie's grateful father, a station agent, taught Edison to operate the telegraph machine, an extremely useful skill.

By 1863, Edison had become an itinerant telegraph operator. Moving from place to place to substitute for operators who had gone to war, Edison worked as an operator for several years. He usually volunteered for the night shift so he could study and tinker during the day.

A visit home in 1868 revealed his family enduring hard times, so Edison realized he needed to take better control of his life. He moved to Boston and began working for Western Union as a telegraph operator. By the end of the year, he made a fateful decision. He resigned from Western Union to devote his full effort to “bringing out inventions.”

His first invention was a vote recorder for the Massachusetts legislature. However, legislators were uninterested in rapid vote recording. They actually wanted less speed so they could have more time to discuss, filibuster, and persuade their colleagues. Edison's first invention was thus abandoned as a failure.

His next effort, an improved stock ticker, was only a little better. A system for sending more than one message over a single telegraph wire (called a duplex) seemed promising, so Edison borrowed $800 to build the equipment. He then convinced the Atlantic & Pacific Telegraph Company to let him give it a test over their wires, sending multiple messages from Rochester to New York. It failed miserably, even though the next issue of the National Telegraphic Union's magazine, the Telegrapher, reported it as a “complete success.”

Edison left Boston for New York and arrived there flat broke and in need of a job. In New York, he contacted his friend, Franklin Pope, a well-respected telegrapher, author, and editor of the Telegrapher (and possibly a participant in the duplex test). Pope was also chief engineer for the Laws Gold Reporting Company, which ran a service that relayed gold prices via wire from the New York Gold Exchange to several hundred brokers’ offices. The company had no job for Edison, but Pope arranged it so Edison could sleep in the company's basement battery room until he found work. Having no other place to go, Edison accepted. After business hours, he had the run of the place and soon figured out how the machinery worked. In the middle of a business day, the transmitter quit, and the office became crowded with messengers from the brokerage houses, wanting current gold prices. Although he wasn't an employee, Edison was present and almost immediately found and repaired the problem (a broken spring). The following day, Edison was made Pope's assistant by the company's owner, Dr. Samuel Laws. Within a month he had Pope's job (at $300 per month) when Pope resigned to become an independent consultant. Within three months, Edison improved the operation and applied for some patents. He found himself an employee of Western Union again when that company bought the Laws Gold Reporting Company in 1871.

Through several more inventions and improvements on telegraphic and printing equipment, including waxed paper for mimeograph machines, Edison was rewarded with a huge payoff from Western Union: $40,000 (almost $8 million in 2015 dollars). With this money, Edison set up his first workshop in Newark, New Jersey. More inventions followed, mostly dealing with telegraphic equipment. Edison also took time to marry and start a family. Their first child, Marion, was born in 1872, followed by a son, Thomas Jr. in 1876. They were nicknamed Dot and Dash. Eventually, Edison and his assistants outgrew the early lab spaces and moved to Menlo Park, New Jersey. Within a year of the move, Edison invented the phonograph, and a year later he was hard at work on an incandescent lamp. The principle was simple enough: run an electric current through a material that would heat up and glow brightly enough to provide light. The difficulties included finding a material for the filament that would last, attaching the electrical contacts to the filament securely, finding the right shape for the bulb, and maintaining a vacuum inside the bulb to prevent the hot filament from reacting chemically. Edison's assistants tested a huge number of materials before settling on carbonized thread in a highly evacuated bulb. By late December 1879, a hastily rigged system of electric power generation, distribution, and lighting was set up for public viewing at Menlo Park. Since the current flowed only in one direction, it was called direct current, or DC. The system was a huge success, and people braved stormy weather to see “The Wizard of Menlo Park's” latest invention.

Converting the preliminary system to a commercially viable one took a bit of doing, as well as some time. A dynamo had to be set up to generate the current, bulbs had to be manufactured, and shallow tunnels needed to be dug for the wiring to be buried. One major difficulty was that current flowing through the wires heated them up, so energy was lost in transmission. As long as the customers were located within a mile of the generator, the losses were small. In September of 1882, Edison's Pearl Street Station in Manhattan was finally ready. Before the end of the year, 2,400 Edison bulbs glowed brightly in offices within New York's financial district. But everything wouldn't remain so rosy. Another participant was about to enter Edison's life.


In 1856, Nikola Tesla was born in Croatia in eastern Europe. His father, Milutin, was a Serbian Orthodox priest, and his mother, Ðuka Mandić Tesla, was the daughter of another Serbian Orthodox priest. When Nikola was five years old, he found his older brother's dog dead by the roadside. Dane, his twelve-year-old brother, had been recognized as a child prodigy and was the family's favorite child. Dane was very upset at the dog's death and blamed Nikola. A short time later, Dane suffered an accident (a fall, either from a horse or down cellar stairs) and died from his injuries. Nikola thought his parents blamed him for his brother's accident and worked hard to try to make amends. Nikola was a sickly child, and, destined for the ministry, he became seriously ill several times. As he recuperated from one such illness, he read Mark Twain's Innocents Abroad. In his autobiography, Tesla says it lifted his spirits enough to recover and started him thinking about America. Just after high school graduation, he contracted a serious case of cholera. As he was about to breathe what appeared to be his last breath, he revealed to his father that he hated the clergy and really wanted to be an electrical engineer. His father promised to send him to the best school if he would just recover. He did, and his father made good on his promise.


Nikola Tesla (1856–1943). Used with permission from Sidney Harris.

Tesla attended the Austrian Polytechnic in Graz, and spent many twenty-hour sessions studying electrical engineering. He irritated some of his professors by advancing beyond their knowledge. In an electric motor, a piece of equipment called a commutator was used to force the current to flow only one way and keep the motor turning in one direction. The commutator required contact between rotating parts, leading to frictional inefficiencies. Tesla asked why the commutator couldn't be eliminated. Despite ridicule from the instructor about the current flowing both ways—making it an oscillator rather than a motor—Tesla regarded the idea of designing a motor that had alternating currents a personal challenge. After more studies at the University of Prague (stopping short of achieving a degree), Tesla, in 1881, became the chief electrician for American Telephone and Telegraph Company in Budapest, Hungary. There, he suffered another major illness, which made his senses abnormally keen. Tesla said he could hear a watch ticking three rooms away.

During his recovery, the solution to the problem of the motor with current flowing both ways occurred to him. What he hadn't been able to figure out earlier was that the motor required a rotating magnetic field. The whole design burst upon him complete in all details. What he needed next was a working model, but that would take a while. The telephone station in Budapest was sold, and Tesla went to work for Continental Edison in Paris, where he became the company's troubleshooter. He thrived on long hours of work, rising at 5:00 am for a swim in the Seine, a stroll, and breakfast. He then arrived at the office by 8:30 and usually worked till late evening. After work, Tesla often ate at fancy restaurants, picking up the tab for whoever dined with him. He dressed in elegant clothes and cut a fine figure with his tall, slim frame and piercing blue eyes.

Continental Edison suffered an embarrassing problem (a short circuit blew out a wall) during the dedication of their electrical system at the railway station in Strasbourg. Tesla was sent to patch things up. Since fixing their public failure was important to the company, Tesla was promised a bonus if the repairs were completed quickly and well. While bureaucratic forms delayed the actual repair for days, Tesla found time to work on his AC motor project. He rented a machine shop near his hotel where the necessary parts could be made. There, Tesla built a working model of his new motor. Finally, both projects came together—the repair of the railway electrical system was complete, and his alternating current motor was finished. His Strasbourg friends, including the former mayor, were quite pleased with the repairs to the electrical system, but they were much less enthusiastic about his alternating current motor. When he returned to Paris after completing his assignment, his superiors were similarly uninterested in the motor project. They even failed to pay the bonus for the electrical system repair. They pointed out that very wealthy people had invested heavily in direct current systems and wouldn't be interested in generators that used different means. Tesla's boss suggested he go to America to present his idea to Edison himself.

Tesla quit his job, bought a steamship ticket, and gathered his meager possessions for the trip. As he boarded the train in Paris to begin the journey, his luggage was stolen. Thinking quickly, he boarded the train anyway, spending almost all his pocket money in the process. When he arrived at the embarkation point, he explained the situation to the boat officials. Tesla told them the time and location where he had bought the ticket and the number on it. He reasoned that either the thief would show up with the ticket, or no one would arrive, and he should be allowed to board. Although they were skeptical, the officials agreed to wait. When it was time to sail, and no one had appeared with the ticket, they allowed Tesla to be the last passenger aboard. After changing ships and enduring a rough crossing, Tesla arrived in America in 1884 with the equivalent of 4 cents, the least recorded amount for any immigrant at Ellis Island.


Tesla soon met Edison, who hired him on the spot. Tesla worked for Edison from the summer of 1884 through the spring of 1885, helping to troubleshoot Edison's direct-current electrical systems. Edison was completely uninterested in Tesla's alternating current ideas, since he himself was so thoroughly committed to direct current. Besides, Edison told Tesla, alternating current is “a deadly current, whereas direct current is safe.”4

In addition to the usual difficulties of selling and installing new technology, the price of copper became artificially inflated because speculators were attempting to corner the market. Edison's financial backers were displeased by the slow (in their view) progress and meager profits. Further, Edison had competition, as we'll see shortly. By 1887, Edison was feeling squeezed from several directions.

Edison put Tesla to work redesigning the company's direct-current generators to minimize losses. Tesla said that Edison offered him $50,000 to increase the generators’ efficiency. Tesla worked with characteristic vigor—once for eighty-four hours straight—and completed the improvements Edison wanted. When Tesla tried to collect the bonus, Edison reportedly said, “Tesla, you just don't understand American humor.” Tesla resigned in disgust.

Next, he formed his own company, Tesla Electric Light & Manufacturing. He satisfied his investors by designing an arc lamp for street lighting and industrial use, but the investors forced him out of his own company when he tried to develop the brushless alternating current motor he had designed in Strasbourg.

In 1887 and 1888, Tesla had to dig ditches to make a living, but a sympathetic foreman took him to see a Western Union official, who rounded up new financial backers. They organized the Tesla Electric Company, where Tesla was able to work out the mathematical details and build many different dynamos and motors, including a mechanical oscillator that shook neighboring buildings. In 1890, Tesla was invited to give a lecture to the American Institute of Electrical Engineers, titled “A New System of Alternating Current Motors and Transformers.” He became an instant celebrity and accepted a one-million-dollar-plus-royalties offer for his patents. So, who could afford to offer a cool million? Read on.


George Westinghouse (1846–1914) was born in the small village of Central Bridge, New York. His father manufactured farm implements, which exposed young Westinghouse to machinery at an early age. He and his two brothers served in the Union military during the Civil War. After the war ended, Westinghouse spent a short time at Union College studying engineering. He cut his studies short to become an inventor. In 1865, he obtained his first patent, for a rotary steam engine. The railroad industry caught his attention. He designed a device for getting derailed cars back on the track, another that prevented derailments at switches, and a fail-safe braking system that used compressed air. These were followed by an automatic signaling system, in which electricity was used to indicate the passage of trains. Westinghouse patented his inventions after seeing his first few creations stolen by unscrupulous railroad managers. He started many different companies to produce his inventions and guarded his patent rights fiercely. An innovative employer, Westinghouse paid his workers well, cut the workweek from six days to five and a half, was among the first to institute paid vacations and pensions, and hired the first female electrical engineer. When an exploratory oil well on his property in Pittsburgh produced a gusher of oil and gas, Westinghouse designed and built a distribution system so the gas could be reduced in pressure and safely piped to many homes.


George Westinghouse (1846–1914). Used with permission from Sidney Harris.


In 1884, Westinghouse hired William H. Stanley Jr., an inventor and patent holder in his own right. Not long after, Westinghouse read about a transformer (then called a secondary generator) invented independently by Lucien Gaulard (1850–1888) and John Dixon Gibbs (1834–1912) that was used to step down high-voltage AC to lower voltages suitable for lighting. It occurred to Westinghouse that if high-voltage electricity could be stepped down to lower voltages for home use, that would be similar to his pressure reducer invention. For the transformers to work, this innovation necessitated an alternating current (AC) system, as opposed to Edison's direct current (DC) system currently in vogue. However, AC's major advantage occurred at high voltage. The higher the voltage, the less the current that flows. The net result was that transmission losses could be minimized by stepping the voltage up to higher levels for transmission, then stepping it down for home or industrial use.

Westinghouse bought US rights to the transformer, and Stanley proceeded to improve the design to make it commercially practical. Westinghouse thus entered the electrical business with an AC system in 1886. Edison's DC system had about a four-year head start, but that didn't deter Westinghouse. Westinghouse's company lit several commercial establishments along the main street in Great Barrington, Massachusetts, where Stanley lived and maintained his lab. The AC generator for this system was initially a European import, but Stanley built an improved one. From the electric lighting customers’ point of view, there was little difference between the Westinghouse system and the rival Edison system, also in use in Great Barrington in 1886. Both offered lighting at substantially similar rates (Westinghouse did undercut Edison prices occasionally), but the major differences were Edison's inability to transmit long distances, and Westinghouse's lack of an AC motor for industrial customers. By 1887, after one year in business, Westinghouse had sixty-eight AC systems built or under contract, while Edison had 121. If only Westinghouse had an AC motor, he knew that he could compete with Edison across the entire range of electrical business, besides just lighting.


In 1888, Westinghouse paid the fees to license Tesla's AC motor so he could compete with Edison for industrial customers. Once the motors were built, Westinghouse was able to field a complete lineup of products comparable to Edison's. The major difference was that Westinghouse's AC system didn't require the generator to be within a mile of the customer's location.


The AC/DC competition took a strange turn of events in 1888. On the good side, Edison opened a state-of-the-art lab in West Orange, New Jersey. On the bad side, several people were killed in electrical accidents, mostly electrical company employees who failed to observe safety precautions. These accidents were followed by a scathing letter to the editor of the New York Evening Post about the dangers of AC and how the public was in “constant danger from sudden death” because of AC. The letter writer, Harold P. Brown, a seemingly obscure New York engineer, recommended that AC above three hundred volts be outlawed in the interest of public safety. Truly, there was some danger involved, but it was mostly due to the huge number of overhead wires already in place. They had been strung willy-nilly for arc-lighting systems, telegraphs, stock tickers (including the Gold Exchange), and other private electrical systems. In Brooklyn, the baseball team was nicknamed the Dodgers because Brooklynites had to dodge not only the streetcars but also dangling electric wires.

It seemed like an opportunity was being seized to discredit Westinghouse's AC system, even though that system wasn't entirely to blame. Westinghouse understood this and sent a warm, friendly letter to Edison, proposing peace between the companies. Edison's answer was: “My laboratory work consumes the whole of my time and precludes my participation in directing the business policy.”5 Westinghouse felt as if he had no choice but to fight. He appeared before the New York City Board of Electrical Control and quoted impressive safety statistics that favored his AC system over Edison's DC. By the end of July, Brown struck again. He held a demonstration at Columbia College in which he subjected animals to various electric shocks, trying to demonstrate the danger of AC. When the audience realized what he was going to do, many people left the room. Finally, an agent for the American Society for the Prevention of Cruelty to Animals stood up and forbade Brown to execute any more animals. The hostile audience filed out, with a diatribe against AC bouncing off their departing backs. After several other animal execution demonstrations, Brown began to work on a larger target: electrical execution (electrocution) of convicted murderers with alternating current as a “quick, humane” form of capital punishment. Letters, testimony, legal actions, legal fees, and many attorney-billable hours flew back and forth. The point was that the DC forces wanted to portray AC as a “killing current” so the public would fear it.


In August 1889, the New York Sun published an exposé of Harold P. Brown. Someone broke into his Wall Street office and stole forty-five letters that showed he was paid by the Edison Company and the Thomson-Houston Company. (Edison and Thomson-Houston merged under the control of J. P. Morgan to form General Electric, GE.) Nevertheless, bureaucratic wheels continued to grind onward, proceeding toward the inevitable conclusion. In August 1890, convicted felon William Kemmler was executed in the electric chair at Auburn Prison in New York. Driven by a generator voltage of 1,000 to 1,400 volts, alternating electrical current surged through Kemmler's body for seventeen seconds, and the prison doctor pronounced him dead. As other attending physicians examined Kemmler, his chest suddenly heaved up and down. Quickly, they reattached the electrodes and ran the current for several minutes. Kemmler was finally dispatched, but it was hardly neat or even humane.


The electric current war (and a bulb war) continued in a less bizarre fashion, with the battlefield shifted to financial, governmental, and courtroom venues with small victories for each side. The next big skirmish was Chicago World's Fair of 1893. Both Edison, now backed by financier J. P. Morgan and called General Electric (GE), and Westinghouse/Tesla made bids to light the fairgrounds at night. General Electric's first bid was $1.8 million, later amended to $554,000. Westinghouse won the competition with a bid of $399,000. Edison was so displeased that he refused to sell them GE bulbs, so Westinghouse invented more efficient ones. As the fair opened, President Grover Cleveland pushed a button, and almost one hundred thousand incandescent bulbs lit the buildings and grounds spectacularly. Fairgoers dubbed it “The City of Light.” Tesla's AC system worked perfectly and demonstrated its safety and efficiency to twenty-seven million fairgoers.

The next key battle was fought at Niagara, New York. The Cataract Commission was set up to decide on the best method for extracting energy from the raging Niagara River. After keen (and some not-so-keen) analysis, the commission awarded one contract to Westinghouse's AC system to generate power at the dam, and one contract to Edison's GE to license Westinghouse/Tesla patents for AC transformers and distributions systems and so they could run AC transmission lines to Buffalo, New York, twenty-two miles away. Within a few years, the power grid was 80 percent AC, so Tesla/Westinghouse were definite winners of the “current war.”


Although Westinghouse/Tesla won the Niagara battle, Tesla suffered a crushing setback. His Houston Street lab was completely destroyed in a building fire. All his plans, equipment, and partially completed projects were ruined, and were not covered by insurance. Not long after, Westinghouse's financial backers questioned his royalty agreement with Tesla. When Westinghouse passed along their concerns, Tesla responded by tearing up the agreement. Although it was eventually estimated to have cost him around $10 million, Tesla was optimistic that he would make much more. Tesla's research interests included wireless power transmission (radio), remote control of mechanical devices (robotics), and single-node vacuum tubes (X-rays).

Bonus Material: Tesla/Edison Internet interview. See To Dig Deeper for details.


The principal participants in the AC/DC current war all moved on after the conflict and accomplished plenty. Let's look at each of them.

Edison never rested long. He returned to an earlier interest and upgraded a large ore-crushing mill in Ogdensburg, New Jersey, that he had built earlier. His plan was to crush the ore so finely that electromagnets could separate the iron from the ore. He said, “I'm going to do something now so different and so much bigger than anything I've ever done before; people will forget that my name ever was connected with anything electrical.”6 Technical problems and a soft market made the business a failure, so Edison shut it down. However, one of the manufacturing by-products was sand that he sold to cement manufacturers. It turned out that the sand was of such a high quality that it made excellent cement. So, naturally, Edison next went into the cement business.

Edison's winter retreat in Ft. Myers, Florida, was quite near one of industrialist Henry Ford's homes. The two of them became personal friends and went on camping trips with businessman Harvey Firestone. All in all, Edison remained an inventor until the end. He held 1,093 US patents and 2,332 worldwide. Edison died in 1931 in West Orange, New Jersey.

George Westinghouse returned to an old interest of his: steam turbines. He acquired some patent rights and scaled up an earlier design to such a large size and high speed that it could power dynamos and propel ships. Westinghouse got his first patent at age nineteen and amassed 361 US patents. By 1900, Westinghouse's various companies employed fifty thousand people and were valued at $120 million. In the financial panic of 1907, Westinghouse resigned from all his companies. His health began to deteriorate in 1910, and he died in 1914.

Nikola Tesla had a new lab built in Colorado Springs in 1899, where he experimented with high-frequency, high-voltage systems, cosmic rays, atmospheric electricity, and electric oscillations of the entire earth/ionosphere system. Just after he started up his “magnifying transmitter,” the power demands knocked out the Colorado Springs Electric Company's generator. Tesla's facility was soon closed and dismantled to pay debts. Tesla returned to New York and obtained financial backing from J. P. Morgan to build a laboratory on Long Island, called Wardenclyffe. The Wardenclyffe Tower was designed to be the hub of a world radio and wireless power distribution system. Tesla's plan was to shoot electrical currents (similar to lightning) into the upper atmosphere. A distant receiving station would conduct and distribute the current. The current would then flow into the ground, over a hundred meters deep, and complete the circuit by flowing back to the distribution station at Wardenclyffe. In Tesla's view, the earth and its ionosphere constituted a giant capacitor, with the rest of the atmosphere acting as a dielectric. Delays and cost overruns required more funds, and when Morgan found out that Tesla's ultimate aim was the free distribution of wireless power, he withdrew funding and the project collapsed. Tesla was severely discouraged, and his mental state may have deteriorated. He became more secretive than ever, lived in a succession of hotels (The Waldorf-Astoria, the St. Regis, the Governor Clinton, and the New Yorker), became morbidly afraid of germs (eighteen clean towels per day and dozens of napkins at each meal), and periodically issued grand statements about his current research, but without any evidence. In retrospect, some think he had obsessive-compulsive disorder (OCD). His reputation suffered, and eventually few took him seriously. He died in 1943 and was cremated shortly thereafter. He is still in the public eye, thanks to an opera about him called Velvet Fire that opened in 2004. Tesla is depicted as a modern Prometheus, who suffered mightily because he stole lightning from the gods. There is also a rock group named after him and a very successful electric automobile company.

Perhaps due to the catastrophic fire of 1893, or because of the many business failures, or even due to his secretive nature, Tesla wrote down precious little. He so captured the imagination of the world that many speculations and folk legends have sprung up about yet unknown Tesla ideas and inventions. The web is rife with speculations and rumors, but so far, there is no evidence to support them.

For chapter 8, we're going to return to earth, with a thud. An attractive theory gets no experimental support for the longest time, then…watch.