In 1882, Tesla moved to Paris to work as an engineer for the Continental Edison Company, designing improvements to electrical equipment. According to his autobiography  the same years, he conceived his induction motor and began developing various devices that used rotating magnetic fields, for which he received patents in 1888. The paternity of the invention remains controversial, since a prototype induction motor was demonstrated in Europe in 1885 by Galileo Ferraris. Ferraris published his findings in 1888.
On 6 June 1884, Tesla arrived in New York City with four cents in his pocket, a letter of recommendation, a few poems, and remnants of his belongings. His trip across the Atlantic had not been pleasant; his ticket, money and some of his luggage had been stolen. He had nearly been thrown overboard after a mutiny broke out on the ship.
In the letter of recommendation from Charles Batchelor, a former employer, to Thomas Edison, it is claimed that Batchelor wrote, 'I know two great men and you are one of them; the other is this young man', but the exact contents of the letter is disputed in McNichol's book. Edison hired Tesla to work for his Edison Machine Works. Tesla's work for Edison began with simple electrical engineering and quickly progressed to solving some of the company's most difficult problems. Tesla was even offered the task of completely redesigning the Edison Company's direct currentgenerators.
In 1885, Tesla claimed that he could redesign Edison's inefficient motor and generators, making an improvement in both service and economy. According to Tesla, Edison remarked "There's fifty thousand dollars in it for you - if you can do it". This has been noted as an odd statement from an Edison whose company was stingy with pay and did not have that sort of cash on hand. After months of work, Tesla finally finished the task and inquired about payment. Edison claimed he had been only joking and replied, "Tesla, you don't understand our American humor". Edison offered a US$10 a week raise over Tesla's US$18 per week salary, but Tesla refused it and immediately resigned.