138 : Ttie Atlantic 



In 1427 Diogo de Seville, in command of Henry's vessels, began the 

 discovery and exploration of the Azores, which continued until 1431. 

 An Italian chart of 1351, the Medici Portolano, showed some islands 

 in the ocean that might have been intended as a representation of 

 the Azores, but it is even more probable that they were simply imag- 

 inary islands since, as we have seen, classical geographers often re- 

 ferred to such mythical islands as Atlantis and the Hesperides. The 

 islands may have been discovered on the first extended cruise of the 

 Portuguese ships in the Atlantic beyond the longitude of Madeira, 

 but it seems more likely that their discovery was due to the fact that 

 Henry's vessels had for some time been adventuring into the Atlantic. 



In 1425 Henry sent out an expedition that was bent on conquest 

 rather than mere discovery. It was the intention of the expedition to 

 take the Canary Islands away from Castile. He also tried to secure the 

 islands by negotiation so that he could have a base for further expedi- 

 tions in Africa and be free of rivalry in the development of African 

 trade. 



Another attempt at conquest was made in 1450 to 1453 but when 

 a treaty was finally drawn, after Henry's death, it provided that Cas- 

 tile (Spain) retain the Canaries while Portugal was assigned the West 

 African coast, Guinea, Madeira and the Azores. 



That, however, is getting ahead of the story. In the meantime, Hen- 

 ry's progress down the African coast was slow. It took a decade of 

 effort before one of Henry's vessels passed Cape Bojador in 1433, but 

 a year later they had gone as far as the Senegal and in 1445 Diniz 

 Diaz discovered and rounded Cape Verde. Relative to the desert coasts 

 that lie north of it the name is well chosen for on the cape and about 

 the shores of Dakar harbor there are some palm trees and other signs 

 of vegetation that look bright to eyes that have been gazing only on 

 water and sand, though no one could say that the vegetation of the 

 cape was luxuriant. From this point on, Henry's captains were re- 

 warded in their long search of the African coast. They came into a 

 strip of coast where the African natives were eager for trade. Soon as 

 many as twenty-five ships a year were making the passage between 

 Portugal and the African coast. 



Henry's work was now in full stride and in 1455 an Italian cap- 

 tain in his employ, named Cadamosto, explored Africa extensively by 

 sailing up both the Senegal and the Gambia Rivers. He was also 

 responsible for the discovery of the Cape Verde Islands. The busy trade 

 with the African coast continued until Henry's death in 1469. By 

 this time the African movement that Henry had sponsored had pro- 



