STORY OF A MOUNTAIN.
Before us rises a high mountain. Its top is white with snow. Its sides are steep and rocky and very hard to climb. made the mountain? Has it always been there, or is it a little hill grown large and high? Mountains really do grow. Is that not strange? They were once lower than they are now. They began as little hills long ago and slowly kept getting larger. When mountains stop growing they do not remain always. They are wearing away, and after a long time may change to, little hills again. Let us see if we can understand how this is done. A moun tain will interest us more when we know its story.
Some mountains are formed by the rising of the solid land on which we live. The land wrinkles in furrows and ridges. You can see how this is done by taking a piece of paper in your hands: when the paper is stretched out it is even like a plain; shove the opposite edges of the paper toward each other and it will wrinkle. There will be a ridge, and then a hollow, and then a ridge again.
At first the ridges upon the earth where moun tains are forming are not higher than hills, but they keep rising and rising until they reach, it may be, two or three miles into the sky.
You can not see mountains grow, because they do so very slowly. You would have to watch many thousands of years to see one change a great deal.
You have all heard of earthquakes, I am sure. At such a time the land trembles under our feet. The strongest buildings are sometimes thrown down. In places where mountains are growing we often have earthquakes. In the western part of our country we can see places where the land has changed its level fifty feet at the time of an earthquake.
The mountain which rises so white in our picture is a volcano. It is one of the highest mountains in the United States and is called Mount Shasta. Volcanoes are formed in a different manner from other mountains.
Have you ever heard what volcanoes are made of, and how they have buried whole cities? In Italy there is a volcano that buried two cities for so long a time, that people living near forgot that the cities had ever been there.
Volcanoes are built of lava and ashes which are thrown out of an opening in the earth. Far down beneath our feet the rocks are very hot. In some places they are hot enough to melt. If there is any water in them it is changed to steam. The steam tries to get out just as it tries to escape from the boiler of an engine. Where it finds a weak place in the crust of the earth it makes a hole. Around this opening a volcano may be built up. Melted rock, pieces of solid rock, and ashes are blown out through the opening. After a time enough accumu lates to form a mountain.
If you can visit a furnace you may see melted iron which looks much like hot lava from a volcano. The clinkers from a coal fire look like the lava when it has become cold.
We have seen how the river is at work making the valley in which it flows. We have seen that mountains are furrowed with gulches and canons made by the raindrops. The muddy streamlets after a rain are carrying the land away from the mountain sides.
Do you not think that after a long time many streamlets could wash the mountain entirely away? If yoU should work long enough you could carry away a haystack by taking one straw at a time.
The snowy mountain which our picture shows will not last always. Every spring when the snow melts the streamlets are working as fast as they can carrying the particles of soil and rock down to the valley. Some time the mountain may be worn down and only a hill left in its place.