A Few Facts about the Sea

4.8

Why the sea is never still.

There are times when the sea is almost still. But even when the sea looks like glass, there are waves in it. They are so small, that we cannot see them. But the sea is almost always moving, and it moves because the air above it is moving. So it is the wind which makes the waves.

It is true that you can see great waves in the sea though there is no wind. But you may be sure that the wind has made these waves somewhere else. Perhaps they have traveled hundreds of miles before you see them.

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Can you find fresh water in the sea?

Large quantities of fresh water are found at some places in the sea. You can very often find fresh water at the mouth of large rivers where large quantities of fresh water are spread over the surface of the sea for many miles.

The Amazon River, for example, pours out into the sea more than a million cubic feet of fresh water a second, and you can find it on the surface two hundred miles from shore. Ships which needed fresh water often took it from the sea near the mouth of the Amazon.

Sailors tell a very interesting story. Once near the mouth of this river a ship saw another ship which was signaling: “Water, water! We are dying of thirst!” From the other ship went back the advice: “Drop your pails where you are.” But the first ship could not understand and signaled again and again, always with the same result. At last the captain commanded to drop the pails into the sea, and they were pulled out full of fresh water from the Amazon’s mouth.

But you can get fresh water from the sea in another way. Much of the rain which falls on earth sinks through the soil till it reaches a layer of rock, which is a hundred feet below the surface of the ground. The water runs along the top of this layer of rock, and finally makes its way up through the sea as a submarine spring.

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Everybody can float in the Dead Sea.

Even if you cannot swim well, you can swim in the Dead Sea, because it is so heavy with salt (25 per cent) that people seem light by comparison.

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The depths of the sea are black.

The depths of the sea are black because not even the slightest sun’s light can penetrate down more than half a mile. Sea creatures which live at the depth of the sea are either blind or have their own phosphorescent “lighting system”.

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Sea water boiling-point.

Sea water boils at a higher temperature than pure water, because salts in it raise the boiling-point.