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drink contains mineral matter, though we may not taste it.

Animals and people get most of the mineral matter which is needed for bone-tissue through the water which they drink and in the vegetables and fruits which they eat.

When we eat salt, and some other substances, we are taking the mineral matter directly into our bodies. All mineral matter taken into our bodies is absorbed by the blood. The blood carries it to the parts of the body which need it. In the same way the bony part of the bodies of all animals is built up.

In plants the mineral matter is the hard part which gives shape to the

leaves and an upright position to the stalk. The glaze, on the outside of the stalks and grain of all the members of the Grass Family, consists of mineral matter. This mineral substance is taken up in solution by the rootlets. It is carried by the sap to the different parts which need it.

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In some instances the water becomes greatly heated in its underground passage and comes to the surface as hot-springs. Some of these springs throw out, at intervals, great spouts of hot water. Such springs are called Geysers.

There are celebrated geysers in the Yellowstone National Park, U.S. A., in Iceland, and in New Zealand. In many localities of the world there are numerous hotsprings which do

salt,

not spout. If you leave the sweet, or alum solution in a shallow dish, the water will evapo rate. Little grains or crystals of each-salt, sugar, and alum-will be left. When the water which thrown out by the geyser

evaporates or flows away, it leaves a solid mass of matter as in the picture of "Pulpit Rock."

Visit all springs in your neighborhood. Compare one with another. Make experiments as suggested. Observe and state results. Tell how soils are necessary for the life of plants, animals, and man. Make a collection of different soils. Bring in pictures which show the wearing of rocks.

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the space on each side of the channel into a valley. Little hills are left between these valleys.

After the rain the stream-bed or gully may dry like the one in the upper picture on the preceding page. But when

The carrying of soil by the streams takes place everywhere on the earth dur ing a heavy rain or when the snow is rapidly melting from the hill or mountain sides.

As the rain falls you notice that the water is at once separated. A part flows down one side of the ridge or hill in little streams or feeders, and a part down the other side. It is parted or divided by the rise or ridge of land.

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the next heavy rain comes the channel will be cut deeper, more soil will be carried from the valley sides, and larger hills will be left between the valleys. This will continue until the stream has cut its channel down to the level land. HILLS and VALLEYS are being carved by the action of water during heavy rains all over the earth.

When the rain is very heavy great quantities of soil are loosened. All of the streams are muddy. This tells us that they have washed the loose dirt or soil from their pathway and are carrying it to a lower level. The small streams which are doing this work are called brooks.

Ridges which part the water when it falls are called WATER PARTINGS or DIVIDES. The water-parting is the highest line where two slopes meet. As the little streams reach the foot of the slope, they unite with other little streams which flow down the opposite slope. All of these streams form a larger stream which flows between the two slopes.

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Trace the water-partings and the streams in all of the pictures; also in the schoolyard or in the street. Trace the limits of the different stream basins in the pictures. Find the valleys. Find different stream basins in your neighborhood. What is a brook basin?

Most villages and cities are in valleys and on plains. Many farms are among the hills. Some city people build beautiful

homes among the hills be

cause it is usually more healthful, and restful, than in the valleys.

You will find that nearly all highways lead down the hillside into the valleys; that nearly all railroads and trade

centers are in the

valleys. Can you think

of any reasons for this?

Visit the hills near your school. Observe the plants and trees which grow on them. What plants grow near the top? What near the foot? Which must get the most moisture? On which side of the hill do the plants get the most sunlight? In the spring note on which side the snow melts last. Can you think why?

Clear water does not wear down the valleys as rapidly as muddy water. Can you think why? Where is it cooler-on the summit of a hill, or in a valley? Can you think why it is often so warm in a

valley? Where is it often foggy? Where do you see the sun last at sunset, on the hilltop or in the valley.

The HORIZON is the line where the earth and sky seem to meet. It is the line which bounds our vision. Point to it. Find the horizon in the pictures of land and water which we have studied.

Go to the top of a hill and tell all that you

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pictures brooks. a portfolio.

can see within

your horizon.

In many parts of the world other children can see similar earth fea

tures within their hori

zon.

At what season would you like to live down in the valley? At what season on the hilltops? What are some of the advantages of living among the hills at all seasons? What are some

of the disad

vantages? Bring in

of all kinds of hills, and of

Arrange them neatly on a chart or in

Describe each of the scenes on this page. What grow beside the meadow brook? Which flows more swiftly, the meadow or the mountain brook? Describe the winter scene. In the picture find where the water falls from one layer of rock to another layer of rock in the mountain brook. This is a waterfall. You can see where it flows rapidly over a rocky bed. These are rapids.

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