Ever since the days of Al-ex-an´der the Great, if not sooner, a certain amount of trading had been done with the East. But as all the silk, sugar, spices, etc., had to be brought by coasting vessels to the head of the Per´sian Gulf or the Red Sea, and thence overland by caravans to some port on the Black Sea or the Mediterranean, they became very costly. [Illustration: A Caravan.] Sometimes, too, the goods were brought all the way from China or India, or the heart of Africa, through deserts and over mountains to the Black, the Mediterranean, or the Red Sea, by caravan, although it took a long while to travel all those weary miles. For some time the Turks allowed this trade to go on, but by and by they began to treat the traders so badly that the traffic almost stopped. The cities of Ven´ice and Gen´o-a in Italy, whose ships had constantly sailed to and fro in the Mediterranean and Black seas, to carry these goods from port to port, were now nearly idle, and the people who had grown so rich were about to become poor. As the Turks were too strong to be driven away, the traders longed to find another road to reach India, Cathay, and Ci-pan´go, or Japan. A way of reaching these countries by sea was what they most desired, because it is much easier to carry goods in ships than on camels. The Ve-ne´tians and Gen-o-ese´, however, were not the only ones who wished to find a new road to the East. Many of the European coast cities fancied that if they could only discover it, they could keep the trade all to themselves, and thus grow richer and more powerful than their neighbors. One of the countries which most coveted the Eastern trade was Por´tu-gal, where a bright boy was heir to the throne. This lad, Prince Henry of Portugal, once went with his father to Ceu´ta in Africa. Although then very young, he listened eagerly to the wonderful stories told about Guin´ea, on the southern side of the Sa-ha´ra. He soon began to wonder if it would not be possible to get there by sailing along the coast instead of crossing the African desert. This, you must know, was a great undertaking, because people found nothing to eat or drink there, and suffered much from the heat. Besides, the wind called the simoom raised such clouds of dust that whole caravans were sometimes buried in the sand. By looking at the maps in your geography, you can see that it was easy to sail from Portugal to Guinea; but at that time people knew nothing of the west coast of Africa. Prince Henry, in hopes of solving the problem, began to study very hard. Before long he read in an old book that a wise man thought it possible to sail all around Africa, and he longed to find out if this was true.