The Travels of Marco Polo — Volume 1 by Marco Polo and da Pisa Rusticiano

took an interest in Geography, and devoted labour to geographical compilations, in which they often made use of their own observations, of the itineraries of travellers, and of other fresh knowledge. But somehow or other their maps were always far behind their books. Though they appear to have had an early translation of Ptolemy, and elaborate Tables of Latitudes and Longitudes form a prominent feature in many of their geographical treatises, there appears to be no Arabic map in existence, laid down with meridians and parallels; whilst _all_ of their best known maps are on the old system of the circular disk. This apparent incapacity for map-making appears to have acted as a heavy drag and bar upon progress in Geography among the Arabs, notwithstanding its early promise among them, and in spite of the application to its furtherance of the great intellects of some (such as Abu Rihán al-Biruni), and of the indefatigable spirit of travel and omnivorous curiosity of others (such as Mas’udi). [Sidenote: Marino Sanudo the Elder.]