Fra, the most celebrated cosmographer of his time, was a friar of the Order of Camaldolesi, in the monastery of St Michele di Murano, near Venice. He flourished in the fifteenth century; but the date of his birth and death are alike unknown. The fame he had acquired in the physical and mathematical sciences caused him to be chosen, in 1444, member of a commission of fifteen Venetian patriachs, who were intrusted by government to regulate the course of the River Brenta, and to direct the work relating to the lagunes. Between 1437 and 1459 he made his celebrated map of the world, which has been so frequently copied, and which may still be seen in his monastery near Venice. In that singular production the progress of geographical science is marked with the utmost precision. In addition to the travels of Marco Polo, Fra Mauro marked down Cape Verde, Cape Roxo, the Gulf of Guinea, and all he could learn from the navigators of that day, who have left no written account of their voyages. Thus, Darfur, unknown to Europe till the time of Bruce, is mentioned under the name of Dafur. He also took notice of what was known to the Arabs, who at that time had pushed their discoveries on the coast of Africa as far as Sofala, and even visited Madagascar. The highest glory of Fra Mauro, however, was the efficient aid he rendered to the two greatest expeditions of modern times, which resulted in the discovery of the Cape of Good Hope and the continent of America. His map is the first in which the E. and W. coasts of Africa are made to approach each other till they almost form a point, clearly indicating the passage round the Cape. There also may be seen beyond the Azores (slantly indicated and erroneously marked, it is true) several islands named Antilles and Brazil; and it is precisely by these names that Columbus and Vespucci distinguished the land they first discovered; thus favouring the conclusion that it was on the faith of Fra Mauro's map of the world that they were incited to their bold and immortal discoveries. Alphonso V. of Portugal requested Fra Mauro to draw a planisphere to serve as a guide to the intrepid Portuguese mariners, who had already endeavoured to find a passage to the East Indies; and we gather from a writer of the time (Francis Alvarez), and from the account-book of the monastery of S. Michele, that a copy of the map still existing there was given to the captain of two caravels sent out on a voyage of discovery in 1487, and paid for by King Alphonso. The Venetian Republic ordered a medal to be struck, on which may be seen the likeness of Mauro surrounded by the inscription, "Frater Maurus S. Michaelis Moranensis de Venetiae Ordinis Camaldonensis Cosmographus incomparabilis." The last and most complete account of the planisphere is that by the Cardinal Placido Zurlo: Il Mappamondo di Fra Mauro de critto ed illustrato, Venezia, 1806.