In 1443, an expedition of six caravels, commanded by a gentleman of the Portuguese court, went down the coast on one of these ventures, ostensibly geographical, but really mercenary, which then excited the popular enterprise. It managed to attack some island and to make a great number of prisoners. The same year a citizen of Lisbon fitted out a vessel at his own expense, went beyond the Senegal, where he seized a great many natives, discovered Cape Verde, and was driven back to Lisbon by a storm. Prince Henry built the fort of Mina upon the Gold Coast, and made it a depot for articles of Spanish use, which he bartered for slaves. He introduced there, and upon the island of Arguin, near Cape Blanco, the cultivation of corn and sugar; the whole coast was formally occupied by the Portuguese, whose king took the title of Lord of Guinea. Sugar went successively to Spain, Madeira, the Azores, and the West Indies, in the company of negro slaves. It was carried to Hayti just as the colonists discovered that negroes were unfit for mining. Charlevoix says that the magnificent palaces of Madrid and Toledo, the work of Charles V., were entirely built by the revenue from the entry-tax on sugar from Hayti. At first, all prisoners taken in war, or in attacks deliberately made to bring on fighting, were sold, whatever their nation or color. This was due to the Catholic theory that all unbaptized people were infidels. But gradually the same religious influence, moved by some scruples of humanity, made a distinction between negroes and all other people, allowing only the former to become objects of traffic, because they were black as well as heathen. Thus early did physiology come to the aid of religion, notifying the Church of certain physical peculiarities which seemed to be the trade-marks of the Creator, and perpetual guaranties, like the color of woods, the odor of gums, the breadth and bone of draught-cattle, of their availability for the market. What renown has graced the names of Portuguese adventurers, and how illustrious does this epoch of the little country's life appear in history! Rivers, bays, and stormy headlands, long reaches of gold coast and ivory coast, and countries of palm-oil, and strange interiors stocked with new forms of existence, and the great route to India itself, became the charter to a brilliant fame of this mercenary heroism. Man went as far as he was impelled to go. While the stimulus continued, and the outlay was more than equalled by the income and the glory, unexplored regions yielded up their secrets, and the Continent of Africa was established by this insignificant nation to be for centuries the vast slave-nursery of the world.