Granville T Woods


Graville T Woods was known as the “Black Edison”. He was an extremely creative and brilliant inventor of electro-mechanical devices. His inventions produced broader and more efficient applications of electricity. Woods’ early genius for modifying and improving electrical apparatus was unmatched during the Industrial Revolution.

A native of Columbus, Ohio, he attended school until the age of ten. Woods travelled to Missouri at the age of 16, and worked as a fireman-engineer on the railroads. Afterwards, he travelled east to study electrical and mechanical engineering, and was able to obtain a job on a British steamer, the Ironside, where he remained for two years.

By 1881, he opened a factory in Cincinnati, Ohio and manufactured telephone, telegraph and electrical equipment. He filed his first application for a patent in 1884 for an improved steam-boiler furnace. Later that same year, he invented a telephone transmitter. His transmitter could carry the voice over longer distances, with greater clarity and more distinct sound.

A year later, Woods patented an apparatus he coined “telegraphony,” a combination of the telephone and telegraph. As a result, telegraph stations could send both oral and signal messages over the same line and enabled inexperienced telegraph operators to send messages without benefit of knowing the Morse code. Woods sold this invention to the American Bell Telephone Company.

Woods produced one of his most important inventions in 1887: a device called the Synchronous Multiplex Railway Telegraph. It enabled messages to be sent to and from moving trains and railway stations. Serious accidents were now avoided because conductors could be forewarned of obstacles in their path. Another key invention was a regulator, which greatly increased the efficiency of electric motors. Demands for his electrical devices became so widespread that he abandoned his company to devote full-time to further inventions.

After relocating to New York City in 1890, Woods became a patron of the arts. It was while attending the theatre that he became fascinated by the way theatre lights were gradually “dimmed.” However, this dimming system was known to cause electrical fires, so he set out to improve this lighting system by creating an efficient, safe and economical dimmer. His system was not only safer, but resulted in a 40% energy savings.

Woods was also responsible for modernising our transportation system. He invented an overhead conducting system for electric railways still utilised by trains and trolley cars today. He also invented the electrified “third rail,” now used by subway systems in large cities such as Chicago, New York and elsewhere. In 1901, this invention was sold to the General Electric Company in New York.

Granville T Woods was awarded more than 35 patents for his electrical innovations. In 1890, he introduced an electrically heated egg incubator, which made it possible to hatch 50,000 eggs at one time. He also invented a relay instrument, an electromechanical brake, a galvanic batter, an automatic safety cut-out for electromechanical brake, a galvanic battery, an automatic safety cut-out for electrical circuits, and many other devices. At the time of his death in 1910, more than 150 patents had been awarded to Granville Woods. His achievements attracted universal attention and high praise from the scientific community worldwide.