And so, returning from Africa in 1418, the Prince retired to the famous Sacred Promontory in the Province of Algarve, where he gave the best energies of forty years to the task of African exploration. Backed by the resources of the state, commanding the best scientific knowledge of the day, patiently enduring "what every barking tongue could allege against a Service so unservicable and needlesse," he sent out year after year the most skillful and daring sailors of Italy and Portugal, and inspired them anew, as often as they returned baffled and discouraged, with his own perennial enthusiasm. Between 1435 and 1460, famous captains in his service--Gil Eannes, Denis Diaz, the Venetian Cadamosto--made those crucial voyages round the Point of Bojador, past the desert to Cape Verde, and beyond as far as Sierra Leone. After 1443 the labors of the Navigator were no longer thought to be wasted; for when the rich traffic in slaves and gold was opened up to Portugal, the greed of gain was added to scientific interest as a motive for exploration:--"Gold," says the chronicler, "made a recantation of former Murmurings, and now Prince Henry was extolled." When Prince Henry died in 1460 no ship had sailed beyond Sierra Leone; but the nation had caught the spirit of the master, and in the next generation the search for India replaced the exploration of the Gulf of Guinea. Escobar crossed the Equator in 1471, and fourteen years later Diego Cam sailed a thousand miles beyond the mouth of the Congo River. It was in 1486 that Bartholomew Diaz, third of that family to forward African exploration, left Lisbon determined to reach the Indian Ocean. Having passed the farthest point reached by Diego Cam the year before, he put out to sea and ran before the strong northern gale for fourteen days. Turning eastward in search of the coast, and then north, land was at last sighted to the west. The northerly trend of the coast, as they pushed on four hundred miles farther, assured Diaz that he was, indeed, in the Indian Ocean. The valiant captain would have gone on to India, but the crew forced him to turn back. It was on the return voyage that he first saw the southernmost point of Africa--object of so many notable ventures: the Tempestuous Cape, as Diaz would have named it; but no, replied the king, may it rather prove the Cape of Good Hope.