Thomas Edison

Thomas Alva Edison invented hundreds of devices, including the phonograph. He also developed a method of organized scientific research that hastened advances in American technology.

Early years

Thomas Edison was born on February 11, 1847, in Milan, Ohio . Edison's father was a jack-of-all-trades, and his mother was a former teacher. As a child, Edison spent only three months in school. His mother educated him herself at home. At the age of twelve, he went to work, selling fruit, candy, and newspapers on the Grand Trunk Railroad. During his teens, Edison lost his hearing, possibly caused by the scarlet fever he had as a child.

In 1862, Edison got an opportunity to learn telegraphy, a means of communicating over a great distance by using coded signals transmitted by wire. He soon mastered the art and for the next five years traveled throughout the country as a telegraph operator. During these years, he dreamed of becoming an inventor. He frequently purchased electrical gadgets or chemicals for his laboratory.

First inventions

Not long after Edison went to work for Western Union Telegraph Company in Boston, Massachusetts , in 1868, he invented a device for electronically recording the voice votes taken in a legislative assembly. For this machine, he obtained his first patent, a grant made by the U.S. government that assures an inventor the exclusive right to manufacture, use, and sell the invention for a stated period of time. The machine worked well, but no one was interested in buying it.

In June 1869, Edison moved to New York City to work for an electrical firm. He soon formed his own electrical engineering company and

invented a stock ticker, a machine that printed out stock quotes that came in through telegraphy. He sold the company, with the ticker, for $40,000.

Invention factories

Using the money from the sale of his company, Edison opened an “invention factory,” a lab for research in Newark, New Jersey . The factory employed as many as eighty researchers, including chemists, physicists, and mathematicians. It operated for six years, turning out a variety of inventions related primarily to improvements in stock tickers and telegraphy equipment.

In 1876, Edison built a new invention factory in Menlo Park, New Jersey. Over the next ten years, he produced many important inventions, including the phonograph and an improved incandescent lightbulb.

The phonograph

Edison's most original and lucrative invention, the phonograph, or record player, was patented in 1877. The idea for the phonograph came to Edison while he was studying a telephone receiver. He attached a steel stylus (a hard-pointed, pen-shaped instrument) to the diaphragm (a disk that vibrates to generate sound waves) of the receiver so he could feel the sound vibrations with his finger as they were emitted. It dawned on him that the stylus might “etch” the vibrations onto a piece of moving tinfoil. He reasoned that a similar point could then trace the grooves left on the foil and pass the vibrations onto another diaphragm to produce sound. His original phonograph used a tinfoil-covered cylinder that was hand-cranked, while a needle traced a groove on it. By 1890, his phonograph had become a motor-driven machine playing cylindrical wax records.

The incandescent lightbulb

Edison did not invent the incandescent lightbulb, but he designed one that worked well and was cheap enough for everyone to buy. The concept of the lightbulb was simple enough: When an electrical current passes through a thin wire, or filament, it encounters resistance that causes the wire to become hot enough to glow, that is, to reach incandescence. The heat caused the wire to burn too quickly, so scientists encased the wire in a vacuum, a space devoid of matter. Edison tested ideal materials for use as the filament in a lightbulb. On October 21, 1879, he publicly demonstrated an incandescent bulb that burned continuously for forty hours.

The first central electric-light power plant

In 1878, Edison and other investors created the Edison Electric Light Company, which was later the General Electric Company. At that time, everyone who used electricity had to have their own dynamo, or generator. Edison opened the first commercial electric station in London in 1882, providing electric power to buildings in the area of the station. Within months, he opened the Pearl Street Station in New York City, lighting more than 5,000 lamps for 230 customers. Many towns and cities soon installed central stations.

A new lab

In 1887, when his laboratories outgrew the facilities at Menlo Park, Edison built an even larger invention factory in West Orange, New Jersey. By this time, his labs were so productive that he was receiving an average of one new patent every five days. The West Orange factory, which Edison directed from 1887 to 1931, was the world's most complete research laboratory, the forerunner of modern research and development laboratories, with teams of workers systematically investigating problems.

Probably the best-known invention of the late 1800s was the kineto-graph, a primitive form of the moving picture. Edison developed a method for arranging a series of photographs on a strip of celluloid film and then running the film through a projector. He used this technique in 1903 to produce The Great Train Robbery, one of the first moving pictures.

Edison's active nature and inquisitive mind led him to wander from subject to subject. Sometimes he stayed with a project long enough to see it to commercial production, and sometimes he spent time developing the early stages of an idea and then moved on to something new. Among the many inventions to which he made a contribution are the lead storage battery, the mimeograph machine (a copying machine), the dictaphone, and the fluoroscope (a type of X-ray machine).

Edison died in West Orange on October 18, 1931.