A. B. (Alfred Bray) Kempe

Born in London on 18 July 1849, Alfred Bray Kempe studied at St Paul's School and then at Trinity College, Cambridge, where he graduated as a mathematician. Although he trained in mathematics, he also built a legal career and was called to the bar at the Inner Temple.

Kempe became well known in mathematics for publishing an 1879 proof of the four-colour theorem. The proof was accepted for years before Percy Heawood found a flaw in 1890, but Kempe's methods still influenced later work on the problem. He also wrote important papers on geometric linkages and on the algebra of logic, showing an unusual range of interests.

He was elected a Fellow of the Royal Society and later served as its Treasurer. Kempe died on 21 April 1922, leaving behind a reputation as a creative and wide-ranging thinker whose work connected Victorian mathematics, logic, and mechanics.