Tropic of Cancer (0.468″) of latitude, or 15 metres, per year (it was at exactly 23° 27′N in 1917 and will be at 23° 26'N in 2045). See axial tilt and circles of latitude for further information. North of the tropic are the subtropics and the North Temperate Zone. The equivalent line of latitude south of the Equator is called the Tropic of Capricorn, and the region between the two, centered on the Equator, is the tropics. There are approximately 13 hours, 35 minutes of daylight during the summer solstice. During the winter solstice, there are 10 hours, 41 minutes of daylight. Starting
Regio Patalis the habitability of lands under the Torrid Zone and Tropic of Capricorn, D'Ailly drew on the "Opus Majus", written around the year 1267 English monk and scholar Roger Bacon. With regard to the "Regio Patalis," Bacon said: “the southern frontier of India reaches the Tropic of Capricorn near the Region of Patale and the neighbouring lands which are washed by a great arm of the sea flowing from the Ocean”. Patala was on or just south of the Tropic of Cancer, not south of the Equator, but somehow Roger Bacon had confused the Tropic of Capricorn with the Tropic of