Edison had just started his job at Western Union in Boston when he faced his first test. Observing his usual shabby attire, his new coworkers assumed he was a country bumpkin. To embarrass him, they put him to work transcribing a long message coming in on the New York wire that they had arranged to have sent by New York’s fastest operator. “After a few minutes,” Edison recounted later, “his gait got very rapid . . . Turning my head, I found nearly every operator in the office watching me from behind. I knew then that they had put up a job to roast me.”

The Boston operators soon found out that the bumpkin was sharper than he looked. With his training, Edison was able to stay four or five words per minute ahead of the incoming message - at least until the sender started to abbreviate his words. “As I had to write out in full, I knew that soon I would have to break, so to save the day I opened the key and said ‘You seem to be tired, suppose you send a little while with your other foot.’ After this, I was all right with the other operators.”

Edison tended to inspire respect and loyalty among his colleagues. No matter how hard he had to work, how many hours he spent at a machine, how unpleasant his living conditions, he remained cheerful. He was the eternal enthusiast, intensely involved with his work, leaving no room for boredom or discontent.

Edison’s never-ending cheer was all the more remarkable because he was growing deaf. His deafness may have been the result of scarlet fever or a series of ear infections, but the cause has never conclusively established. Edison had two theories. Initially, he attributed it to a conductor who boxed his ears after his rolling lab caught fire, but later, he offered another explanation, also dating to his time on the railroad. Once, he said, while talking to his newspaper customers, he nearly missed the train: “I ran after it and caught the rear car nearly out of wind and hardly able to lift myself up, for the steps were high . . . . A trainman reached and grabbed me by the ears, and, as he pulled me up, I felt something in my ears crack, and right after that I began to get deaf.”

The ever-buoyant Edison even came to view his handicap as an advantage, one that added to his legendary powers of concentration. “While I could hear unerringly the loud ticking of the [telegraph],” he once said, “I could not hear other and perhaps distracting sounds. I could not even hear the instrument of the man next to me in a big office.” Seven years later, working on the telephone transmitter, he claimed his deafness had again given him an edge since he had to increase the volume so he could hear it - an improvement that made the telephone more practical. When working on the phonograph - “my baby,” as he called it - his deafness forced him to put his ear against the machine and actually bite its wood casing, which amplified the vibrations through his jawbone. This odd way of listening, he decided, enabled him to “hear better than anybody else.”

In the 1860s, Boston was America’s center of higher education and a hotbed of scientific experimentation, particularly in the embryonic field of electrical engineering. Shortly after he arrived, Edison visited a shop owned by Charles Williams Jr. on Court Street, which made hand-crafted, high-quality electrical and telegraphic instruments, including some of America’s first fire-alarm boxes. Here, he could continue to work on his experiments and make a few dollars.

Edison also discovered a new source of inspiration in Michael Faraday, a brilliant English scientist who had pioneered experiments in electromagnetism. Edison bought a second-hand copy of Faraday’s two-volume Experimental Researches in Electricity and was impressed by the scope of Faraday’s knowledge and achievements. He immediately set out to replicate the experiments of the great man, who had died a year earlier at the age of seventy-five.

“I am now twenty-one,” Edison told his roommate, Milton Adams, after finishing Faraday’s book. “I may live to be fifty. Can I get as much done as he did? I have got so much to do and life is so short, I am going to hustle.”

Edison began to attract investors willing to finance his inventions. One of the first to receive funding was his Stockbroker Printing Instrument, his enhancement of the telegraphic stock ticker, a device invented in 1867 by a man named Edward Callahan. Edison didn’t pioneer the broadcasting of stock prices by telegraph, but he did improve the speed, quality, and reliability of the way prices were printed on the ticker tape. One device he invented was the screw-thread unison, which kept the printing spools in the receiving machines in sync by using an electric signal.

With his stock ticker, Edison set up a small transmission service for Boston clients. “I established a laboratory,” he later recalled, “and put up a line on which I opened a stock quotation circuit with twenty-five subscribers, the ticker being of my own invention.” He climbed onto the roofs of houses to install the wires himself, selecting buildings that already had Western Union lines. “It never occurred to me to ask permission from the owners,” he said. His first customer was the Boston office of the Kidder, Peabody & Company securities firm.

With his stock-price service, which he began in January 1869, Edison made enough money to quit his job at Western Union. He took out an ad in the Telegrapher, an industry newspaper, announcing, “T. A. Edison has resigned his situation in the Western Union office, Boston, and will devote his time to bringing out inventions.”

One of those inventions, the electric vote recorder, was way ahead of its time. Edison came up with the idea after spending long hours in the Western Union office waiting for election results to be transmitted over the wire. Votes at the time were tallied by hand - a tedious process followed by every legislature from federal and state assemblies to city councils. In Edison’s design, each legislator would move a switch to the yes or no position, which would transmit an electrical signal directly to the clerk.

What seemed like a simple and obvious solution to a time-consuming problem was not embraced by its potential customers. The vote recorder was rejected first by legislators in Massachusetts and then in Washington, D.C., where lawmakers actively opposed Edison’s invention. The problem, he discovered, was that politicians were accustomed to taking advantage of the delay of manual counting to change their colleagues’ minds and garner additional votes. “This is exactly what we do not want,” one seasoned politician scolded Edison. “Your invention would not only destroy the only hope the minority would have in influencing legislation, it would deliver them over - bound hand and foot - to the majority.”

By the time the vote recorder failed, Edison had already started working on another idea, this one also stemming from his experience as a telegrapher. When the telegraph was first invented, only one message at a time could be sent through a system. Clearly, significant time and money could be saved if operators could cram more data into the wires. Other inventors had tried to solve the problem; in 1867, a Boston entrepreneur, Joseph Stearns, had patented the duplex telegraph, which could send two messages over the same wire by varying the frequency of the signals.

Edison made what he considered significant improvements to the duplex process. Hoping to test his system, he asked Western Union if he could rewire its Boston network, but the company turned him down. Edison then contacted a rival, the Atlantic & Pacific Telegraph Company, which agreed to let him use its Rochester-New York City wire to try out his new system. In April 1869, Edison traveled to Rochester but couldn’t get the signals to transmit. After several failed attempts, he admitted defeat. Edison later blamed the failure on the incompetence of an assistant at the New York end.

Now broke and frustrated and unable to obtain further financing from his Boston backers, Edison borrowed a few dollars from a friend and boarded a boat for New York City. It was time to try his luck on a bigger stage.

With no cash in his pockets, except for a dollar he managed to borrow from a telegrapher he knew in New York, Edison walked to the offices of Gold & Stock Reporting Telegraph Company, owned by Samuel Laws, who in 1867 had introduced his Gold Indicator - a three-spooled device that displayed price changes on the trading room floor of the New York Gold Exchange.

At Gold & Stock, Edison called on Franklin Pope, a telegrapher familiar with Edison’s stock-ticker operation in Boston. Pope invited Edison to work on his experiments at Gold & Stock’s machine shop and offered him a cot in the company’s battery room.

In the heady, inflation-prone years of Reconstruction, gold was a hot and furiously traded commodity. By the time Edison had arrived in New York, Gold & Stock had extended its pricing service to Manhattan brokerages, transmitting the information via private telegraph lines - similar to what Edison had done on a smaller scale in Boston. In an industry where price changes had previously been relayed by messenger boys, Laws’s innovation was a major breakthrough. Edison was fascinated.

One summer day in 1969, Edison was watching the Gold & Stock machine in action when it broke down. In the panic that ensued, gold brokerage firms sent hundreds of agents swarming into the company’s headquarters. Neither Franklin Pope, the telegrapher, nor Samuel Laws himself, who had studied engineering at Princeton, could figure out what had gone wrong or how to fix it. Laws, whose lucrative brokerage business was in danger of being ruined, was, as Edison later recalled, “the most excited person I have ever seen.”

As Laws and Pope shouted at one another, Edison examined the mechanism and found that a spring had come loose and fallen in between two gears, jamming them. Within two hours, he had removed and reset the spring and had everything up and running.

Impressed with Edison’s quick wits and mechanical skill, Laws invited the young man to his office the next day, where Edison told Laws about his own stock ticker and offered suggestions on how Laws could improve the performance of his machines. Laws hired him on the spot, putting him in charge of all the company’s technology, for the sum of $300 a month, an astounding amount of money to a young man who owned one threadbare suit and could barely afford to eat. Reminiscing about his pay years later, Edison recalled: “This was such a violent jump from anything I had ever had before that it rather paralyzed me for a while. I thought it was much too good to be lasting; but I determined to try and live up to that salary if twenty hours a day of hard work would do it.”