The Portuguese war with Tangiers now absorbed the entire naval and maritime resources of the country, and the plague of Lisbon stayed for a time the patriotic enterprises of Don Henry. In 1440-42, expeditions sent in the same direction resulted in the capture and transfer of several Moors to Portugal, and in the payment to their captors, as ransom, of the first GOLD DUST ever beheld by Europeans. A river, or arm of the sea, near the spot where this gold was paid, received, from that circumstance, the name of _Rio del Ouro_. This gold dust at once operated as a sovereign panacea upon the obstinacy and irritation of the public mind. It has been well remarked that "this is the primary date to which we may refer that turn for adventure which sprang up in Europe, and which pervaded all the ardent spirits in every country for the two succeeding centuries, and which never ceased till it had united the four quarters of the globe in commercial intercourse. Henry had stood alone for almost forty years; and, had he fallen before those few ounces of gold reached his country, the spirit of discovery might have perished with him, and his designs have been condemned as the dreams of a visionary." The sight of the precious metal placed the discoveries and enterprises of Don Henry beyond the reach of detraction or prejudice. Numerous expeditions were successively fitted out:--that of Nuno Tristan, in 1443, who discovered the Arguin Islands, thirty miles to the southeast of Cape Blanco; that of Juan Diaz and others in 1444; that of Gonzalez da Cintra in 1445, who, with seven others, was killed fifty miles south of the Rio del Ouro,--this being the first loss of life on the part of the Portuguese since they had undertaken their explorations. In 1446, a gentleman of Lisbon, by the name of Fernandez, determined to proceed farther to the southward than any other navigator, and accordingly fitted out a vessel under the patronage of the prince. Passing the Senegal River, he stood boldly on till he reached the most western promontory of Africa, to which, from the number of green palms which he found there, he gave the name of Cape Verd. Being alarmed by the breakers with which this shore is lined, he returned to Portugal with the gratifying news of his discovery. In 1447, Nuno Tristan sailed one hundred and eighty miles beyond Cape Verd, and reached the mouth of a river, which he called the Rio Grande, now the Gambia. He was attacked by the natives with volleys of poisoned arrows, of the effects of which all his crew and officers died but four; and the ship was at last brought home by these four survivors, after wandering two months upon the Atlantic. The next expedition, under Alvaro Fernando, carried out an antidote against the poisoned shafts of the enemy, which successfully combated the venom, as all who were wounded recovered.