Book XIV covers geography, describing the Earth, islands, promontories, mountains and caves. The earth is divided into three parts, Asia occupying half the globe, and Europe and Africa each occupying a quarter. Europe is separated from Africa by the Mediterranean, reaching in from the Ocean that flows all around the land. Isidore writes that the "orbis" of the earth, translated by Barney as "globe", "derives its name from the roundness of the circle, because it resembles a wheel; hence a small wheel is called a 'small disk' ("orbiculus")". Barney notes that "orbis" "refers to the 'circle' of lands around the Mediterranean, and hence to the total known extent of land." Isidore illustrated the "Etymologies" with a circular T-O map which also gave a vague impression of a flat disc-shaped Earth, though authors disagree about Isidore's beliefs on the matter.