A、The idea that it reached out to "the end of the world". B、The idea that it would be too hot at the equator. C、The idea that it

The Atlantic Ocean is one of the oceans that separate the old world from the new. For centuries it kept the Americas from being discovered by the people of Europe.
    Many wrong ideas about the Atlantic made early sailors unwilling to sail far out into it. One idea was that it reached out to "the edge of the world". Sailors were afraid that they might sail right off the earth. Another idea was that at the equator the ocean would be boiling hot.
    The Atlantic Ocean is only half as big as the Pacific, but it is still very large. It is more than 4,000 miles wide where Columbus crossed it. Even at its narrowest spot it is about 2,000 miles wide. This narrowest place is between South America and Africa.
    Two things make the Atlantic Ocean rather unusual. For so large an ocean it has very few islands. Also, it is the world’s saltiest ocean.
    There is so much water in the Atlantic that it is hard to imagine how much there is. But suppose no more rain fell into it and no more water was brought to it by rivers, it would take the ocean about 4,000 years to dry up. On the average the water is a little more than two miles deep, but in some places it is much deeper. The deepest spot is near Buerto Rico. This "deep" measures 30,246 feet—almost six miles.