Tesla's patents caught the attention of one of America's boldest industrialists. Their partnership put Tesla's motor at the center of a fierce commercial and public battle over which kind of electricity would power the country.

George Westinghouse

George Westinghouse had made his fortune inventing the railway air brake. In the mid-1880s he moved into electricity, buying rights to AC transformer technology from Europe and building AC lighting systems. He lacked a practical motor. In July 1888, shortly after Tesla's lecture, Westinghouse bought Tesla's AC patents for a package of cash and stock and a royalty, reported at $2.50 for each horsepower of electrical capacity sold. Tesla spent about a year in Pittsburgh helping Westinghouse engineers adapt his motor to their system, a process that proved harder than expected, partly because Westinghouse's system used a different frequency.

The war of the currents

Thomas Edison had invested heavily in DC. As AC systems spread, his company and allies launched a campaign to persuade the public and lawmakers that AC was deadly. High-voltage AC lines strung on poles in cities did cause fatal accidents, especially among linemen. Edison argued that AC's high voltages were inherently dangerous and pushed for laws to limit them. Historians call this struggle the war of the currents.

The campaign took a grim turn. An electrician named Harold Brown, working with help from Edison's laboratory, publicly electrocuted dogs and other animals with AC to demonstrate its danger. At the same time, New York State was seeking a more humane method of execution than hanging, and chose electricity. Brown and Edison's allies arranged for the new electric chair to use Westinghouse AC generators, obtained without Westinghouse's consent, so that the public would link AC with death. Edison's side even suggested that executing someone be called being “Westinghoused.”

The first execution by electric chair, of a man named William Kemmler, took place in August 1890 at Auburn Prison in New York. It went badly: the first shock did not kill him, and a second, longer shock was needed. Witnesses were horrified. Westinghouse reportedly remarked that they could have done better with an axe.

A myth about an elephant

One story often told about the war of the currents is false in its usual form. In 1903, at Coney Island, an elephant named Topsy, who had killed a man, was put to death with poison, strangling and electricity, and the event was filmed by a company owned by Edison. Popular accounts often claim Edison killed the elephant to discredit AC. But by 1903 the war of the currents was long over, and there is no evidence that Edison was personally involved. The story shows how a real campaign can attract exaggerated legends.

Westinghouse wins

Despite the campaign, AC won on its merits. Its ability to send power over long distances made it cheaper and more flexible. In 1892 Edison's company merged with a rival to form General Electric, which then also adopted AC. The decisive public moment came at the World's Columbian Exposition in Chicago in 1893. Westinghouse won the contract to light the fair, underbidding General Electric, and illuminated it with around a hundred thousand lamps powered by AC. Millions of visitors saw the “White City” glowing at night. Tesla had his own exhibit there, demonstrating motors and wireless lamps.

The royalty contract

A famous story says that around 1891, when Westinghouse's company was in financial trouble, Tesla tore up his royalty contract to save his friend's company, giving up a fortune. The story became central to Tesla's legend as a man who cared more for progress than money. The details are uncertain. What records do show is that in 1897 Westinghouse paid Tesla a lump sum of about $216,000 to buy the patents outright, ending the royalty. That was a large sum, but far less than the royalties might have earned over the life of the patents. Either way, Tesla gave up a chance at great wealth, and he spent most of what he received on his research.

Worked example: fear, facts and competition

The war of the currents is a case study in how businesses can use public fear in a competition. Separate its elements.

• A real risk. High-voltage AC lines did kill people, and safety rules were badly needed.
• A self-interested messenger. Edison's company stood to lose money if AC won. Its warnings were not purely about safety.
• Manipulation. Electrocuting animals in public and secretly arranging for the electric chair to use a rival's equipment were attempts to create an emotional association, not to inform.
• The outcome. Better insulation, buried cables and regulation reduced the danger, and AC's real advantages won out.

The lesson applies to many later technology fights. When a company warns about a rival's product, ask whether the risk is real, whether it can be managed, and who benefits from the fear. Both sides of a dispute can be partly right: AC was dangerous if handled carelessly, and it was also the better system.