Meanwhile, the Spanish and the Portuguese had been active in seeking for southern routes to the East, and had discovered two,――one around the Cape of Good Hope and one through the Strait of Magellan. They guarded these waterways jealously, and would not allow the ships of other nations to pass. Thus they succeeded in controlling all the rich Eastern trade, and were growing very wealthy and powerful. The English and the Dutch, who were also anxious to obtain a share of the rich commerce with the East, saw the importance of finding a northern route to India; consequently they experimented by sailing northeast along the coast of Europe and Asia. The route which they sought was known as the northeast passage. England sent out the first expedition in 1553, but the severity of the weather prevented the ships from making much progress. Several other vain attempts were made by the English, and then the Dutch took up the work; but they failed, too, and for a time the search for northern passages to the Indies was abandoned. [Illustration: THE EARTH ON JUNE 21.] The total absence of the sun from the Arctic regions during a large part of each year makes the climate severe and the country desolate. Direct sun rays are necessary to insure warmth, and the regions within the Arctic circle receive at the best only slanting rays. [Illustration: THE EARTH ON DECEMBER 21.] In the temperate zones the sun is never exactly overhead. For people who live within the tropics it is overhead twice every year. At all places along the equator the sun is overhead at noon on the 21st of March. Each day after, it comes overhead at noon at places farther north, until the 21st of June, when it is overhead at the tropic of Cancer. After this the sun appears to turn and go south, and on September 22 it is again overhead at noon at the equator. The sun then continues to move southward each day until December 21, when it is overhead at the tropic of Capricorn. And so it goes back and forth the year round. While the sun is north of the equator, there is constant day somewhere within the Arctic circle; when the sun is south of the equator, there is constant night somewhere within the Arctic circle. The farther a region is from the equator, the longer are the days and nights at different seasons of the year. At the pole there is a night of six months and a day of six months. The night is sometimes lighted by the moon and sometimes by the aurora borealis. [Illustration: DAILY MOTION OF THE HEAVENS AS SEEN AT THE NORTH POLE.]