In the attempts to solve this problem Portugal took the lead. Her sailors boldly ventured farther and farther down the coast of Africa until, about twenty years before Columbus discovered America, they crossed the equator. But it was not till five years after the memorable exploit of Columbus, that Vasco da Gama, a Portuguese captain, rounded the Cape of Good Hope and crossed the broad Indian Ocean to India. Two years later he returned home with his vessels full of rich merchandise from that country. =8. The Shape of the Earth--Spherical or Flat?=--The learned men of that age, for the most part, believed the earth to be round like a ball. But the common people, and doubtless many of high rank, thought the land surface to be flat, with a flat ocean flowing around it on every side. Now if the earth were really a sphere, and no larger than was commonly supposed, it would seem that the easiest way to get to India, unless unforeseen obstacles intervened, would be to strike out to the west and sail straight across the "Sea of Darkness," as the sailors called the Atlantic. To embrace so startling a theory and deliberately to risk his life in testing its truth, required a man of keen sagacity, of lofty faith, of unbending resolution, and of the most heroic daring. Such a man was Christopher Columbus. =9. Columbus; his Early Life as a Sailor.=--He was born at Genoa, in or about the year 1445. He was the son of a poor wool-comber, and while yet very young he helped in his father's daily toil. We find him a studious boy, early able to write a good hand and to draw maps and charts for mariners visiting his home. He loves the sea, listens eagerly to old sailors' "yarns," weaves their fancies and legends into his day-dreams, and is fired with ambition to go in search of strange lands. How shall he realize his visions? Who will believe in him? At the age of fourteen he becomes a sailor. He sails south along the African coast, and north as far as England, and even to Iceland. Always observing, studying, planning, the ardent, thoughtful boy grows up an earnest, thoughtful man. He is convinced that the earth is a globe, and that, if he sails west far enough, he will reach India by a route shorter than any to the east. Nothing can shake his faith in this belief. It becomes the inspiration of his life. But like that of many learned men of his day, his estimate of the distance is widely wrong. He supposes it to be only a few thousand miles, requiring but a few weeks' sail. Little does he imagine that directly in his westward path lies a vast continent, and beyond this rolls an ocean far wider than the Atlantic!