About the year 1433, one Gilianez, a native of Lagos, whom the prince had entrusted with the command of a vessel, returned from an unsuccessful attempt to conquer the invincible obstacles which obstructed the passage round Cape Bojador. He had been driven by stress of weather into one of the Canary islands, and had imprudently seized some of the inoffending natives, whom he brought captives to Sagres. Don Henry was much offended by this conduct of Gilianez, whom he received with much coldness and reserve; insomuch that Gilianez, on purpose to retrieve the princes favour, and to make ample amends for the fault he had committed, made a vow, that if entrusted with a new expedition, he would perish rather than return unsuccessful in the enterprize which the prince had so much at heart. The date of the second expedition of Gilianez, in which he surmounted the terrors and difficulties of Cape Bajador, is variously referred by different authors to the years 1433 and 1434. However this may have been, he succeeded in this herculean labour, as it was then esteemed, and returned with great exultation to Sagres, where he was again received into the favour and confidence of Don Henry. Contrary to the assertions, or suppositions rather, of the discontented opposers of the patriotic and enlightened efforts of Don Henry, Gilianez reported that the sea beyond Cape Bojador was perfectly susceptible of navigation, and that the soil and climate were both excellent.
In the following year Gilianez again sailed for the coast of Africa, accompanied by Alphonzo Gonzales Baldaya, cupbearer to the prince. The weather continued favourable during the voyage, and they were able to penetrate ninety miles to the south of Cape Bojador. On landing to take a view of the country, and in search of inhabitants, they found the former to consist for the most part of an extended desert plain, and they were much disappointed in not being able to meet with any of the inhabitants, though they saw evident traces of them in the sand. To the bay in which they landed they gave the name of Angra dos Ruyvos, or Bay of Gurnets, from the great abundance of fish resembling gurnets which were taken by the seamen.