The first commercial use of an electrical telegraph is successfully demonstrated in London by William Cooke and Charles Wheatstone.
Electrical telegraph
Electrical telegraphy is point-to-point distance communicating via sending electric signals over wire, a system primarily used from the 1840s until the late 20th century. It was the first electrical telecommunications system and the most widely used of a number of early messaging systems called telegraphs, that were devised to send text messages more quickly than physically carrying them. Electrical telegraphy can be considered the first example of electrical engineering.
William Fothergill Cooke
Sir William Fothergill Cooke was an English inventor. He was, with Charles Wheatstone, the co-inventor of the Cooke-Wheatstone electrical telegraph, which was patented in May 1837. Together with John Ricardo he founded the Electric Telegraph Company, the world's first public telegraph company, in 1846. He was knighted in 1869.
Charles Wheatstone
Sir Charles Wheatstone was an English physicist and inventor best known for his contributions to the development of the Wheatstone bridge, originally invented by Samuel Hunter Christie, which is used to measure an unknown electrical resistance, and as a major figure in the development of telegraphy. His other contributions include the English concertina, the stereoscope and the Playfair cipher.