Monthly Archives: February, 2013

Who invented the umbrella?

When it rains, we may put up an umbrella to help keep the water off.  But actually the umbrella was not invented as protection against rain. The first umbrellas were used as shades against the hot sun.  in fact, the umbrella gets its name from an old Latin word meaning “little shadow.” No one knows …

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Why do we feel pain when we are hurt?

Heat of the candle flame sends pain messages to the brain through long threads of nerve cells. Consider yourself  lucky that you can feel pain.  Pain is your protector.  It warns of possible danger to the body.  If you did not feel pain from touching something hot, you might not jerk your hand away in …

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How are bricks made?

The ordinary bricks that a bricklayer uses to build a brick house are usually made from clay that is baked in an over. To make bricks, he brick makers grind the clay and mix it with water.  Some sand is added, too. A brick making machine pushes the soft clay through a hole to form …

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Why do we perspire?

The sweat glands help keep you cool in the summer.  When we get very warm, little beads of water called sweat form on our skin.  Perspiration is a quick method of cooling off the body. You can test this by wetting your hands and waving them rapidly.  The water evaporates quickly and makes your hands …

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How are natural diamonds formed?

Diamonds are formed in dying volcanoes.  As the hot lava cools, great pressure and heat act on the carbon found in the lava and change the carbon into diamonds. You may know that a diamond is simply a crystal of common carbon, of which coal is largely formed. Diamonds were formed millions of years ago in …

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How are glass bottles made?

Glass bottles, such as pop bottles and mil bottles, are made by machines which blow and mold the glass at the same time into the right shapes. In the bottle-making factory, a gob of red-hot molten glass with just enough material to make the finished bottle is dropped into a metal mold. A blast of …

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What does ‘dew point’ mean?

The dew point is the temperature at which moisture in the air begins to condense. Perhaps the air doesn’t seem damp at all.  It does, however, have many tiny, invisible bits of water moving about in it.  We call these tiny specks of moisture “water vapor.” Cold air cannot hold as much moisture at warm …

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