Alexander Graham Bell(1847–1922)

Alexander Graham Bell was born at 16 South Charlotte Street in Edinburgh in March 1847, into a family of elocutionists. His grandfather Alexander Bell had taught speech in London; his father Alexander Melville Bell invented 'Visible Speech', a phonetic alphabet for teaching the deaf to articulate. Bell's lifelong work in acoustics, deaf education and the mechanics of speech was inherited rather than chosen.

After his two brothers died of tuberculosis the family emigrated to Brantford, Ontario in 1870, then on to Boston, where Bell took up a teaching post at the Boston School for Deaf Mutes. Through the 1870s he worked in parallel on the education of the deaf — including the lifelong companion who became his wife, Mabel Hubbard, herself deaf from scarlet fever — and on a 'harmonic telegraph' that he hoped would send multiple messages over a single wire. The harmonic telegraph was the path that led, by way of one accidental observation, to the telephone.

On 14 February 1876 Bell filed his telephone patent at the United States Patent Office in Washington. Elisha Gray filed a caveat for a similar device hours later — the priority dispute is one of the most-litigated questions in American patent history. Bell's was patent US 174,465. Three days later, on 10 March 1876, he made the first successful voice transmission to his assistant Thomas Watson in a neighbouring room: 'Mr Watson, come here, I want to see you.' The Bell Telephone Company was founded in July 1877.

What the telephone did is hard to overstate. From the first commercial exchange at New Haven in 1878 to the million-line American network of 1900, the world's communications were rebuilt around Bell's invention in a single generation. By the time Bell died in 1922 the global network had over thirty million subscribers. The company that became AT&T was for most of the twentieth century the largest private corporation on Earth, and the Bell Laboratories arm produced the transistor, the laser, the Unix operating system and the foundational work behind information theory itself. Every modern long-distance call, every radio broadcast, every mobile network, every internet video call traces an unbroken line to a Boston laboratory in March 1876.

Bell himself moved on quickly. After the telephone he worked on hydrofoils, on the photophone — transmitting sound on a beam of light, a direct precursor of fibre optics — and on heavier-than-air flight. He served as the second President of the National Geographic Society from 1898 and shaped the magazine into its modern form. The Bell name today carries the unique weight of being the surname most strongly associated with modern telecommunications worldwide. Bell's birthplace in Edinburgh is marked by a plaque; his summer home at Baddeck on Cape Breton, where he is buried, is a National Historic Site of Canada.