Cause of death: diabetes
Alexander Graham Bell (, born Alexander Bell; March 3, 1847 – August 2, 1922) was a Scottish-born Canadian-American inventor, scientist, and engineer who is credited with patenting the first practical telephone. He also co-founded the American Telephone and Telegraph Company (AT&T) in 1885.
Bell's father, grandfather, and brother had all been associated with work on elocution and speech, and both his mother and wife were deaf, profoundly influencing Bell's life's work. His research on hearing and speech further led him to experiment with hearing devices, which eventually culminated in his being awarded the first U.S. patent for the telephone, on March 7, 1876. Bell considered his invention an intrusion on his real work as a scientist and refused to have a telephone in his study.
Many other inventions marked Bell's later life, including groundbreaking work in optical telecommunications, hydrofoils, and aeronautics. Bell also had a strong influence on the National Geographic Society and its magazine while serving as its second president from 1898 to 1903.
Beyond his work in engineering, Bell had a deep interest in the emerging science of heredity. His work in this area has been called "the soundest, and most useful study of human heredity proposed in nineteenth-century America... Bell's most notable contribution to basic science, as distinct from invention."
Source : Wikipedia