<P> Edison obtained the exclusive right to sell newspapers on the road, and, with the aid of four assistants, he set in type and printed the Grand Trunk Herald, which he sold with his other papers . This began Edison's long streak of entrepreneurial ventures, as he discovered his talents as a businessman . These talents eventually led him to found 14 companies, including General Electric, still one of the largest publicly traded companies in the world . </P> <P> Edison became a telegraph operator after he saved three - year - old Jimmie MacKenzie from being struck by a runaway train . Jimmie's father, station agent J.U. MacKenzie of Mount Clemens, Michigan, was so grateful that he trained Edison as a telegraph operator . Edison's first telegraphy job away from Port Huron was at Stratford Junction, Ontario, on the Grand Trunk Railway . </P> <P> In 1866, at the age of 19, Edison moved to Louisville, Kentucky, where, as an employee of Western Union, he worked the Associated Press bureau news wire . Edison requested the night shift, which allowed him plenty of time to spend at his two favorite pastimes--reading and experimenting . Eventually, the latter pre-occupation cost him his job . One night in 1867, he was working with a lead--acid battery when he spilled sulfuric acid onto the floor . It ran between the floorboards and onto his boss's desk below . The next morning Edison was fired . </P> <P> One of his mentors during those early years was a fellow telegrapher and inventor named Franklin Leonard Pope, who allowed the impoverished youth to live and work in the basement of his Elizabeth, New Jersey, home . Some of Edison's earliest inventions were related to telegraphy, including a stock ticker . His first patent was for the electric vote recorder, U.S. Patent 90,646, which was granted on June 1, 1869 . </P>

Who has been called the greatest inventor of all time