Francis Guthrie

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Francis Guthrie

Francis Guthrie born in London January 22, 1831 - October 19, 1899 Claremont, Cape Town, was a South African mathematician and botanist who first posed the Four Colour Problem in 1852. At the time, Guthrie was a student of Augustus De Morgan at University College, London. He obtained his B.A. in 1850, and LL.B. in 1852 with first class honours. While colouring a map of the counties of England, he noticed that at least four colours were required so that no two regions sharing a common border were the same colour. He postulated that four colours would be sufficient to colour any map. This became known as the Four Colour Problem, and remained one of the most famous unsolved problems in topology for more than a century, until it was eventually proven in 1976 using a controversial computer-aided proof which was lengthy and inelegant.

Guthrie eventually moved to South Africa in 1861 and took up the post of mathematics master at the Graaff-Reinet College. While there he gave some lectures in botany and thus started a life-long friendship with local resident Harry Bolus. He advised Bolus to take up the study of botany to assuage his grief at the loss of his son. When Bolus left for Cape Town a few years later, he persuaded Guthrie to move there as well. For a while he practised at the Bar and edited a newspaper before becoming professor of mathematics at the South African College, which later became the University of Cape Town. He remained there from 1876 until he retired in 1898.

When Bolus undertook to do the family of Ericaceae for Flora Capensis, he enlisted Guthrie's aid and they collaborated until Guthrie's death. Before his death, Guthrie had made an extensive collection of the Cape Peninsula flora, which was eventually housed as the Guthrie Herbarium in the University of Cape Town Botany Department, and used for teaching and reference.

He was described as being warm-hearted, humorous, patient, and unpretentious. The scope of his interests was diverse, and ranged from a lecture titled, “The Heat of the Sun in South Africa”, in which he pointed out that it must be possible to transform solar energy into mechanical power, to aeronautics, where he was involved in the development of the first aircraft. Although dubbed the inventor of the first flying machine, no documentation of his work exists.

Some fynbos species from the Bredasdorp area were named after him: Gladiolous guthriei, Erica guthriei and Homoglossum guthriei, as well as the genus Guthriea Bolus. Cyrtanthus guthrieae was named after his daughter Louisa Guthrie, who was also a botanist.