Perhaps the result of Arabic research, i.e., Ibn-al-Hatham spherical trigonometry, earliest known lens, created new mathematics in the West, the influence of "Muhammad al-Idrisi, circa 1100–1166, Moorish geographer and polymath who drew the Tabula Rogeriana, the most accurate world map in pre-modern times." Wikipedia entry: "Moors"Idrisi is a modern computer GIS (geographical information system) mapping program suite developed at Clark Labs at Clark University in Worcester, Massachusetts. Student-priced versions are available. It is used by many organizations and countries, including the United Nations. I once used parts of it for archaeology mapping for EPA Superfund National Priorities, in the early 1990s. The university I think is where both MD’s, Sigmund Freud and Carl G. Jung were given honorary doctorates.
Library of Congress holds conference on the origin of portolan charts – Washington Post Saturday, May 22, 2010