QI The Book of the Dead

into usable power, what might be achieved if he harnessed the potential of those higher frequencies? Exploring the implications of this insight would dominate the rest of his life.
    In 1884 the twenty-eight-year-old Tesla turned up at Thomas Edison’s office in New York with four cents and some Serbianpoems in his pocket. He had spent the previous two years working for Edison’s company in Paris, and built his first alternating current (AC) motor there in his spare time. Now he was ready to share it with the world. He handed over a letter from his employer in Paris, Charles Batchelor. Addressed to Edison, it said, simply: ‘I know two great men and you are one of them; the other is this young man.’
    Edison wasn’t interested in Tesla’s ideas about AC power; he was building direct current (DC) generators. These were proven to work and his customers liked them. It was Tesla himself who intrigued him. He was an exotic figure: 6'4" tall, a cultured, poetry-loving European, always immaculately dressed in morning coat, spats and gloves. Edison was a shambolic mess of a man who cut his own hair and wore the same food-spattered black clothing every day. About the only thing they had in common was the capacity to survive on virtually no sleep. Tesla’s spooky ability to know the answer to mathematical problems halfway through the question and to conjure phantom engineering diagrams from thin air were in marked contrast to Edison’s ‘99 per cent perspiration’ approach. As Tesla would later remark: ‘If Edison had a needle to find in a haystack, he would proceed at once with the diligence of the bee to examine straw after straw until he found the object of his search.’ But Edison was a shrewd judge of people and had had plenty of practice in turning their ideas into his own money. He hired Tesla for the miserly sum of $18 a week, promising a $50,000 bonus if the young Serb could find a way to make the company’s temperamental DC generator system more efficient.
    Tesla set to the task with his customary application. At first, he was in awe of his new boss. When Edison told him he ateWelsh rarebit every day to increase his IQ, Tesla took the joke to heart and ate barely anything else for weeks. He found Edison’s sense of humour a lot less amusing when, almost a year later, having solved the problem of the DC generator, Edison refused to pay his bonus: ‘When you become a full-fledged American you will appreciate an American joke.’ He offered him a raise to $25 per week instead. It was a mistake Edison would live to regret. Tesla was incandescent with rage and resigned, spending the next year earning his living as a labourer (ironically at one point digging ditches for Edison’s expanding network of DC cables) and working on his inventions at night.
    By early 1887 Tesla had saved enough money to register seven patents covering the full range of AC generators, transformers, transmission lines, motors and lighting. These were awarded unopposed and would become the most valuable patents registered since the telephone. At a stroke, they solved the thorny problem of long-range power distribution. Direct current required a generator to be located within a mile of where the electricity was being used and was inconveniently inflexible: electricity from the same DC generator couldn’t be used to run machines requiring different voltages. To increase the voltage in a direct current circuit meant also increasing the amperage, which meant thicker copper wire and greater loss of energy through heat. With Tesla’s AC solution, power could be generated at a low voltage, then, using a simple device called a transformer, it could be ‘stepped up’ for transmission and ‘stepped down’ again at the customer’s house or business premises. Taking the analogy of a water pipe – the higher the pressure (voltage) the further and faster the same amount of water (electrical energy) will travel, but the hose attachments (transformers) will determine how thatwater is used at the other end. The elegant simplicity of Tesla’s system attracted the attention of Pittsburgh industrialist George Westinghouse. He hired Tesla, purchased his patents for $60,000, and agreed to pay him royalties of $2.50 for every horsepower of AC electricity sold.
    Whether or not Edison saw the writing on the wall, he knew that Tesla and Westinghouse had to be stopped. His war machine rumbled into action. His line of attack was that AC was dangerous.