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 had taught speech in London; his father, Alexander Melville Bell, invented Visible Speech, a phonetic alphabet for teaching deaf people to articulate. Bell's lifelong work in acoustics, the mechanics of speech and the education of the deaf was an inheritance he took up and carried further.

The family emigrated to Brantford, Ontario in 1870, and Bell soon moved on to Boston, taking a teaching post at the Boston School for Deaf Mutes. Through the 1870s he worked in parallel on the education of the deaf, including his future wife Mabel Hubbard, who had lost her hearing to scarlet fever, and on a harmonic telegraph meant to send several messages at once down a single wire. That line of work led him to the telephone.

Bell filed his telephone patent in Washington on 14 February 1876, and United States Patent 174,465 was granted on 7 March 1876. Three days later, on 10 March 1876, he made the first successful transmission of speech to his assistant Thomas Watson in the next 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 within a single generation; by the time he 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 its Bell Laboratories produced the transistor, the laser, the Unix operating system and the foundational work behind information theory. Every modern call, radio broadcast, mobile network and internet video link traces an unbroken line back to a Boston laboratory in March 1876.

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