=146. Need of a sea route to Asia; means of navigation.=—The explorations by land in Asia were of great importance in spreading knowledge of the countries from which the wares of the Levant trade came, but they were of little assistance to traders who sought to develop commerce on the old routes. With the decline of the Mongol power and the spread of the Turks, passage across Asia became constantly more difficult. The available routes finally narrowed to one, that through Egypt, and trade on this route was burdened with very heavy tolls. The European people were urged by powerful economic motives to seek out the sea route to India which was now believed to exist. The means of navigation were still those of the later Middle Ages. The ships in which some of the most adventurous voyages were taken were of fifty tons or even less. The rig had been improved slightly, so that the ships could be handled more readily than when they bore the old square sails; and instruments for ascertaining the position at sea were also improved. Still, when we add to the actual peril of distant voyages the imagined dangers which the minds of men ascribed to unknown seas, we must admit that the early explorers met a test of courage to which men nowadays are rarely put. =147. The lead in maritime exploration taken by Prince Henry of Portugal.=—Italians were, in general, the guides who led Europeans through the seas of darkness to the East. Conditions at home, however, forced them to seek service abroad in realizing their plans, and Portugal was the first of the European countries to effect great oceanic discoveries. The country was small and undeveloped, but it enjoyed in the fifteenth century the guidance of a singularly able line of kings. It had in the person of Prince Henry, “the Navigator,” an enthusiast who devoted practically his whole life and fortune to the cause of discovery. When but twenty-four years old he retired from the world to a promontory at the southern extremity of the country, and there he worked for over forty years, until his death in 1460. Prince Henry combined the commercial motive with missionary zeal and a medieval hostility to the Mohammedans, but the character of his work was entirely modern and business-like. He gave what was most needed for success, organization; he attracted sailors and pilots from all Europe; stimulated development in the science and art of navigation; equipped and inspired expeditions.