2 86 GEOGRAPHICAL SCIENCE. 



Diaz, who had ventured out into the ocean, which was still called the 

 Impenetrable .Sea and the Dark Sea, perceived the Cape of Good Hope, or 

 Stormy Cape, at the extreme end of Africa. 



These African islands and coasts had already been frequented, for in 1471, 

 when the Portuguese landed in Guinea, they were much surprised to find 

 there a French trading depot called Le Petit Dieppe, which sailors from 

 Dieppe had founded a century before. These were the same men who knew 

 of the existence of North America a century before Christopher Columbus 

 discovered the Antilles. Moreover, in 1395, the fleet of the brothers Zeno, 

 freighted at Venice by the traders, had crossed the Atlantic under the 

 guidance of a Dieppe pilot, who pointed out to it the northern coast of 

 America ; but all these discoveries, due to commercial enterprise and the love 

 of gain, and achieved by daring adventurers, were in no way useful to science, 

 for they were kept, secret when they were likely to be beneficial to some 

 branch of maritime commerce, while no importance was attached to them 

 when they resulted in no material gain. It was not until the fifteenth 

 century that navigators began to write an account of their voyages, or to have 

 them recorded by the cosmographers who were generally to be found on 

 board. But these records were either kept secret or were shown to only a 

 very few people, as the navigators looked upon them as property over which 

 it was necessary to keep close watch. Thus the curious voyage of Cadamosto, 

 " Prima Navigatione alle Terre de' Negri " (First Navigation to the Land of 

 Negroes), did not appear until 1507. 



These travels were more useful to map-makers than to geographers, for 

 every traveller and navigator found a map indispensable, and after making 

 one for himself, he added to it the result of his own discoveries. Previously 

 to the fourteenth century maps were very scarce, and those which did exist 

 were faulty and incomplete. The oldest general map of the world dating 

 from the Middle Ages is that which Marino of Venice presented to Pope 

 John XXII. in 1321. This map, which appears to be an imitation of the Arab 

 maps, is nothing more than a picture in which the relative position of places and 

 countries is given almost hap-hazard, without any sign of parallels or meridians. 

 A hundred and forty years later, a Camaldulan monk, Fra Mauro, painted upon 

 the wall of one of the rooms in his monastery, in the isle of Murano, near 

 Venice, an immense planisphere, in which he grouped all the known geographical 

 facts of his time. The first marine maps, drawn by Italian, Portuguese, or 



