Graphs and NetworksMaps

In 1852, the botany student Francis Guthrie (1831 – 1899) was a South African botanist and mathematician, who first stated the Four Colour Problem in 1852. He was a student of Augustus De Morgan, one of the greatest British mathematicians. In addition to being a mathematics professor and teacher, Guthrie worked as a lawyer and did research in solar power and aeronautics.
During the following 100 years, many mathematicians published “proofs” to the four colour theorem, only for mistakes to be found later. Some of these invalid proofs were so convincing that it took more than 10 years to discover errors.
For a long time, mathematicians were unable to either prove that four colours are enough, or to find a map that needed more than four colours.