As Columbus grew older and made maps and studied the sea, and read books and listened to what other people said, he began to believe that this man named Pythagoras might be right, and that the earth was round, though everybody declared it was flat. If it is round, he said to himself, "what is the use of trying to sail around Africa to get to Cathay? Why not just sail west from Italy or Spain and keep going right around the world until you strike Cathay? I believe it could be done," said Columbus. By this time Columbus was a man. He was thirty years old and was a great sailor. He had been captain of a number of vessels; he had sailed north and south and east; he knew all about a ship and all about the sea. But, though he was so good a sailor, when he said that he believed the earth was round, everybody laughed at him and said that he was crazy. "Why, how can the earth be round?" they cried. "The water would all spill out if it were, and the men who live on the other side would all be standing on their heads with their feet waving in the air." And then they laughed all the harder. But Columbus did not think it was anything to laugh at. He believed it so strongly, and felt so sure that he was right, that he set to work to find some king or prince or great lord to let him have ships and sailors and money enough to try to find a way to Cathay by sailing out into the West and across the Atlantic Ocean. Now this Atlantic Ocean, the western waves of which break upon our rocks and beaches, was thought in Columbus's day to be a dreadful place. People called it the Sea of Darkness, because they did not know what was on the other side of it, or what dangers lay beyond that distant blue rim where the sky and water seem to meet, and which we call the horizon. They thought the ocean stretched to the end of a flat world, straight away to a sort of "jumping-off place," and that in this horrible jumping-off place were giants and goblins and dragons and monsters and all sorts of terrible things that would catch the ships and destroy them and the sailors. So when Columbus said that he wanted to sail away toward this dreadful jumping-off place, the people said that he was worse than crazy. They said he was a wicked man and ought to be punished.