But the waves can also be huge and terrifying as if the ocean were angry. Under a winter's cloud, the ocean can appear sullen or fierce. It was a great forward step when man invented a boat so that he could sail out upon the water. He could look for better fishing grounds in a boat. Then ships were made larger and could carry freight.
Heavy freight is more casilv carried over water than over land.
With larger boats, the seas that had separated lands became easy connections between them. In the early days men sailed only the small, almost enclosed seas. It was not until just before 1500 that men began to sail freely on the world ocean. Before this date men knew only 7 per cent of the waters of the world. Suddenly they discovered the vast remainder.