Courageous and persistent, he prepared all his schemes with the utmost thoroughness, and all the help that science could afford, and he carried them out with unfaltering resolution. All through his life he acted up to his French motto, _Talent de bien faire_, which we may translate by the “love of useful glory” to which, according to the poet Thomson, he roused mankind. And if we do not sit cowering before the unknown on all sides it is to Prince Henry and a few men of similarly keen intellect and stout will that we owe it. It must not be thought that he met with no opposition, apart from the great difficulties that naturally beset all discoverers and innovators. On the one hand, the perils of navigating down the coast of Africa were considered insurmountable, and, on the other, the gains to be derived from it were held to be nugatory. It was not till the first slaves and the first gold arrived that men began to realise thoroughly that Prince Henry was something more than an empty dreamer. No one with less faith, a faith based both on religion and science, would have persevered, as Prince Henry persevered, in face of the slight support at first given by public opinion and the slight success obtained. But, although there were many disappointments and progress was slow, the mysteries of the African coast did gradually recede before his persistency, as year after year he sent out ships with definite instructions based on his maps and scientific knowledge. The death of King João I in 1433 did not seriously interfere with his plans; his brother Duarte gave him every possible support, and the expedition against Tangier in 1437 was not an interruption but rather one aspect of his life-work. Indeed, he was the leading spirit of the enterprise. He and his younger brother, Fernando, obtained from King Duarte the consent for which they had ceased to hope from their father; but Duarte at first, and Pedro throughout, were opposed to the expedition. It set out in August, and the little army of some six thousand men disembarked at Ceuta, and, without waiting for the ships to return to Portugal for reinforcements, marched to attack Tangier. Failing to take the place by storm, the princes settled down to blockade it. The danger of such a course was obvious, but even when the Moors, who trooped down from the hinterland, outnumbered the Christian force by twenty to one they were driven back in a series of magnificent attacks. But the Moorish host continued to grow by scores of thousands daily, and in the second week of October it became apparent even to the fiery heart of Prince Henry that he was embarked on a hopeless enterprise.