It was with this type of vessel that the Madeira and Canary groups were "gained from the secrets of the Ocean;" that the Azores, at a distance of twenty-two degrees west of Portugal, and in the heart of the Atlantic, were discovered and colonised; and that open sea navigation of almost equal boldness was successfully employed in the finding and settlement of the Cape Verdes. Before the end of the year 1446, according to Azurara's estimate, the Infant had sent out fifty-one of these ships along the mainland coast of Africa, and they had passed 450 leagues[229] beyond Cape Bojador, which before the Prince's time was the furthest point "clearly known on the coast of the Great Sea." Also, the work of the "School of Sagres" may perhaps be recognised in Azurara's further claim that "what had before been laid down on the Mappemonde was not certain, but only by guesswork," whereas now it was "all from the survey by the eyes of our seamen," and that "all this coast towards the South with many points our prince commanded to add to the sailing chart." [Footnote 229: Azurara, _Guinea_, ch. lxxviii.] It has been noticed that D. Pedro, according to the Portuguese tradition, presented Henry with a copy of Marco Polo's travels, and a map of the same, either drawn by the explorer himself or by one who knew his works, and belonged to his own city. Thereby, we are told, the work of the Infant was much furthered, and Galvano suggests that the same was extant in 1528, and that it contained many wonderful anticipations of later discoveries.[230] [Footnote 230: "... Venice ... whence he [Pedro] brought a map which had all the circuit of the world described. The Strait of Magellan was called the Dragon's Tail; and there were also the Cape of Good Hope and the coast of Africa.... Francisco de Sousa Tavarez told me that in the year 1528, the Infant D. Fernando showed him a map which had been found in the Cartorio of Alcobaça, which had been made more than 120 years before, the which contained all the navigation of India with the Cape of Good Hope."--Galvano, _Discovery of World, sub ann._ 1428.]