Nikola Tesla

Nikola Tesla arrived in New York in 1884 with four cents, a few poems and calculations for a flying machine in his pocket. He came from Smiljan, a village in the hills of what is now Croatia, where his father, an Orthodox priest, had expected him to follow him into the church. Instead he studied engineering in Graz. The city was hard at first. He worked for Thomas Edison, left after a dispute over money, and spent one hard winter digging ditches for two dollars a day.

What he kept was an idea the century would run on: alternating current. Edison backed direct current, which faded within a mile of its generator. Tesla’s current could ride high-voltage lines across whole states. In 1888 he sold his alternating-current patents to George Westinghouse, and the two kinds of electricity went to war. His won. When the power station at Niagara Falls sent its first electricity to Buffalo in 1896, it was his system doing the carrying, and the great fair that lit Chicago in 1893 ran on it too.

He was never only a man of wires. He steered a radio-controlled boat across a stage in 1898, decades before the word robot was coined. He filed some 300 patents, and engineers still meet him in their textbooks.

Money was the one circuit he never closed. His wireless tower at Wardenclyffe, meant to carry messages and power through the air, ran out of backers and came down for scrap in 1917. He spent his last decades in New York hotels, sometimes unable to pay the bill, feeding pigeons out the window. He died at the Hotel New Yorker in January 1943, alone with his formulas and his birds.

The world kept the current. Every socket on the planet carries it, and the morning alarm, the kettle and this page all run on what he sold for a fraction of its worth.