rapidity. In 1484 Diego Cam reached the mouth of the Congo, sailed a short way up the river, and brought back with him four natives, who quickly acquired enough Portuguese to communicate important information regarding their own country and the coast beyond it. Returning with them in 1485, he proceeded some distance to the southward, but made no extensive discoveries; nor was it until the following year that Bartolomeo Diaz, charged by Joao II with the task of following the continent to its southern extremity, passed from the mouth of the Congo two degrees beyond the southern tropic, and reached the Sierra Parda, near Angra Pequena. From this point he resolved to stand out to sea, instead of following the shore. Strong westerly gales drove him back towards it; and he at length reached Mossel Bay, named by him Bahia dos Vaqueiros, from the herdsmen who pastured their flocks on its shore. He was now on the southern coast of Africa, having circumnavigated the Cape of Good Hope unawares. From this point Diaz followed the coast past Algoa Bay as far as the Great Fish River. Its trend being now unmistakably to the north-east, he knew that he had accomplished his task. Returning towards the Cape, to which he gave the name Cabo Tormentoso, or Cape Tempestuous, he rounded it in the reverse direction to that which he had at first intended, and returned to Portugal.
As the Portuguese exploration of the African coast proceeded during sixty years, the objects with which it was pursued were almost completely transformed; and it illustrates perhaps more aptly than any other episode in European history the transition from the ideas of the crusading age to those of the age of dominant commerce and colonisation. Dom Henrique's conception of a " Greater Portugal" including the island groups of the Atlantic and Bilad Ghana on the Senegal River certainly recalls, and was probably founded on, the Mohammadan dominion which included Southern Spain, the Balearic Islands, and Northern Africa, and which St Louis proposed to replace by a Christian dominion equally comprehensive. To this strictly medieval conception the Iffante added some dim idea of a junction with the Christian sovereign of Abyssinia, to be effected by ascending the Western Nile. Beyond this point we have no reason to conclude that his imagination ever wandered. The transformation began after his death. The new dominion called "Guinea" was ascertained by a rapidly extending process of exploration to be of enormous size; this modest province, as it had seemed in prospect, assumed the proportions and character of a vast and hitherto unknown continent. Twenty-six years of discovery, after the Iffante's death, revealed three times the length of coast which had been made known in the course of a considerably longer period during his lifetime; and the Portuguese sailors had now been brought within measurable distance of the Red Sea and Persian Gulf of India, China, and the Spice Islands. Europe's commerce with the