On the other hand, there is no question but that the Sicilo-Norman enthusiasm for geography exerted an indirect influence on the evolution of geographical knowledge, an influence that was to make itself felt more especially after the close of our period. This enthusiasm for geography was the product of a mingling of Arabic scientific and scholarly traditions with Norman maritime enterprise in an island which occupied a central position in relation to the world of its day. It was an enthusiasm that arose partly from pure love of knowledge but also in very large degree from the practical necessities of a sea-faring people, and it was early applied to the solution of the problems of navigation. In the words of De La Roncière, “The use of coast charts was destined to become general in Sicily; a rational method of navigation to be substituted for the routine of pilotage, and thus the way was prepared for the progressive conquest of the world.”[340] As De La Roncière goes on to point out, the Genoese learned the arts of navigation from the Sicilians in the early thirteenth century and transmitted them subsequently to the Spaniards, Portuguese, French, and English; and a new science of the sea was developed upon the foundations originally laid by Sicilian Moslems and Normans.[341] ORIENTAL IDEAS TRANSMITTED TO THE WEST Besides the classical heritage, the Moslems also transmitted some peculiarly Oriental ideas to the West. Al-Khwārizmī was the author of a treatise with astronomical tables, the translation of which by Adelard of Bath usually goes under the name of _Khorazmian Tables_.[342] The original work was a redaction of a book drawn ultimately from Hindu sources and known as the _Little Sindhind_.[343] Thus it was from Hindu sources, as is shown by this work, that the Mohammedans got their idea of the world center of Arin. Hindu religion, furthermore, contributed something toward the molding of Greek and Moslem doctrines of the periodicity of the universe and of the Great Year—doctrines which became widely known in the West through Hermann the Dalmatian’s Latin translation of the Persian Abū Maʿshar’s book, _The Great Book of the Introduction_, entitled in the Latin, _Liber introductorius in astrologiam_.[344] Hindu influences were also felt in an anonymous but widely read Arabic treatise falsely attributed to Aristotle in the Middle Ages and called _Liber de proprietatibus elementorum_.[345] _ASTRONOMICAL GEOGRAPHY; THEORIES OF THE TIDES_