They knew the continent of Europe, a small part of Asia, and a strip along the northern shore of Africa.

The World as Known Four Hundred Years ago.

They thought this known land was surrounded by a vast body of water that was like a broad river. Sailors were afraid to venture far upon this water, for they feared they would fall over the edge of the earth.

Other seafaring men believed that if they should sail too far out upon this water their vessels would be lost in a fog, or that they would suddenly begin to slide downhill, and would never be able to return. Wind gods and storm gods, too, were supposed to dwell upon this mysterious sea. Men believed that these wind and storm gods would be very angry with any one who dared to enter their domain, and that in their wrath they would hurl the ships over the edge of the earth, or keep them wandering round and round in a circle, in the mist and fog.

It is no wonder that the name "Sea of Darkness" was given to this great body of water, which we now know to be the Atlantic Ocean; nor is it surprising that the sailors feared to venture far out upon it.

These sailors had no dread at all of a sea called the Mediterranean, upon which they made voyages without fear of danger. This sea was named the Mediterranean because it was supposed to be in the middle of the land that was then known. On this body of water the sailors were very bold, fighting, robbing, and plundering strangers and foes, without any thought of fear.

They sailed through this sea eastward to Constantinople, their ships being loaded with metals, woods, and pitch. These they traded for silks, cashmeres, dyewoods, spices, perfumes, precious stones, ivory, and pearls. All of these things were brought by caravan from the far Eastern countries, as India, China, and Japan, to the cities on the east coast of the Mediterranean.

This caravan journey was a very long and tiresome one. Worse than this, the Turks, through whose country the caravans passed, began to see how valuable this trade was, and they sent bands of robbers to prevent the caravans from reaching the coast.

A Caravan.

As time went on, these land journeys grew more difficult and more dangerous, until the traders saw that the day would soon come when they would be entirely cut off from traffic with India and the rich Eastern countries. The Turks would secure all their profitable business. So the men of that time tried to think of some other way of reaching the East.

Among those who wished to find a short route to India was Prince Henry of Portugal, a bold navigator as well as a studious and thoughtful man. He was desirous of securing the rich Indian trade for his own country. So he established a school for navigators at Lisbon, and gathered around him many men who wanted to study about the sea.

Here they made maps and charts, and talked with one another about the strange lands which they thought might be found far out in that mysterious body of water which they so dreaded and feared. It is probable that they had heard some accounts of the voyages of other navigators on this wonderful sea, and the beliefs about land beyond.

There was Eric the Red, a bold navigator of Iceland, who had sailed west to Greenland, and planted there a colony that grew and thrived. There was also Eric's son Leif, a venturesome young viking who had made a voyage south from Greenland, and reached a strange country with wooded shores and fragrant vines. This country he called Vinland because of the abundance of wild grapes. When he returned to Greenland, he took a load of timber back with him.

Some of the people of Greenland had tried to make a settlement along this shore which Leif discovered, but it is thought that the Indians drove them away. It may now be said of this settlement that no trace of it has ever been found, although the report that the Norsemen paid many visits to the shore of North America is undoubtedly true.

Another bold sea rover of Portugal sailed four hundred miles from land, where he picked up a strangely carved paddle and several pieces of wood of a sort not to be found in Europe.

St. Brandon, an Irish priest, was driven in a storm far, far to the west, and landed upon the shore of a strange country, inhabited by a race of people different from any he had ever seen.

All this time the bold Portuguese sailors were venturing farther and farther down the coast of Africa. They hoped to be able to sail around that continent and up the other side to India. But they dared not go beyond the equator, because they did not know the stars in the southern hemisphere and therefore had no guide. They also believed that beyond the equator there was a frightful region of intense heat, where the sun scorched the earth and where the waters boiled.

Many marvelous stories were told about the islands which the sailors said they saw in the distance. Scarcely a vessel returned from a voyage without some new story of signs of land seen by the crew.

The people who lived on the Canary Islands said that an island with high mountains on it could be seen to the west on clear days, but no one ever found it.

Some thought these islands existed only in the imagination of the sailors. Others thought they were floating islands, as they were seen in many different places. Every one was anxious to find them, for they were said to be rich in gold and spices.

You can easily understand how excited many people were in regard to new lands, and how they wished to find out whether the earth was round or not. There was but one way to find out, and that was to try to sail around it.

For a long time no one was brave enough to venture to do so. To start out and sail away from land on this unknown water was to the people of that day as dangerous and foolhardy a journey as to try to cross the ocean in a balloon is to us at the present time.

MARCO POLO.

In the middle of the thirteenth century, about two hundred years before the time of Columbus, a boy named Marco Polo lived in the city of Venice.

Marco Polo.

Marco Polo belonged to a rich and noble family, and had all the advantages of study that the city afforded. He studied at one of the finest schools in the city of Venice. This city was then famous for its schools, and was the seat of culture and learning for the known world.

When Marco Polo started for school in the morning, he did not step out into a street, as you do. Instead, he stepped from his front doorstep into a boat called a gondola; for Venice is built upon a cluster of small islands, and the streets are water ways and are called canals.

The gondolier, as the man who rows the gondola is called, took Marco wherever he wished to go. Sometimes, as they glided along, the gondolier would sing old Venetian songs;