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countries having usually moist weather. The and rapids. This enables boats to have rivers in these dry sections cut deep gorges called a continuous line of transportation and canyons. There are many canyons in the highlands of western United States. Observe those lessens the expense of shipping. How? in the pictures.
Rivers help Rivers and smaller
the lumbermen. streams usually have
How? wooded banks. The
The waterfalls richest farming lands
in our rivers in the world lie in the
have long been flood-plains of the
utilized by man river valleys. Fine pas
for turning millwheels. More and more, how ever, steam is taking the place of water power alone.
The tremendous force of Niagara is used in generating electricity to light and serve as motor
power in cities a GOODRICH FALLS,N.H.
tures lie in
NIAGARA FALLS. the higher land of the valley slopes.
long distance from the fall. The Niagara Falls are Great cities or trade-centers are upon the
one of the wonders of the world. The American rivers. These are connected by railways Fall on the left of the picture is about 165 feet, and boats, which serve as outlets for the and the Canadian Fall is about 150 feet high.
Carefully study and describe each of the pictures products of the great farming districts.
on this page. Observe how the water is wearing Canals are usually made around falls down the rocky ledge in the Yosemite Falls.
Many of the higher mountains of the ice melts, leaving the rock fragments world have rivers of ice flowing for and other material strewn over the some distance down their sides. You ground. Large rivers full of fine soil wonder how they
come from these ice were formed ?
streams. The soil is If you squeeze a snow
carried to the floodball very hard and work
plain or to the sea. it for some time with
Many gravel and your hands, it becomes almost a ball of ice.
sand hills are formed This is caused by the
by the material pressure and warmth of
brought down by your hands.
these rivers. In mountainous lo
Rains wash the calities where there
sand from these sand is a great fall of snow,
hills to the lower the snow does not
land, covering it with a all disappear through
sandy, barren soil. the summer months.
Glaciers, or ice More snow falls each
rivers, are in Alaska, winter for several
Greenland, western years than can melt
Canada and United during the summer, so
States, and on the that the depth is con
mountains of Europe, stantly increasing. The
South America, and great weight of this accu
Asia. mulation, together · with the heat from
There was a time in the
Earth's history when the the sun's rays, causes
cold belts extended much the snow to change
farther towards the to ice. This ice forms
Equator than at the into streams which
present time. After
many, many years there flow slowly down
was a great accumulathe mountain sides.
tion of snow. Through Ice streams tear
pressure and heat this
snow changed to ice, and up trees, plants, and
flowed slowly down the
END OE ULACIER soil, and break off
slopes in streams, or
spread out on the plains large rock masses in
in a broad, continuous their descent. They carry these in the sheet of ice. This ice sheet covered all of the ice to lower, warmer sections, where the northern parts of North America and Europe,
extending across the continent of North America courses down the mountain side. Many in a westerly direction from New Jersey.
people visit the regions where the ice How do we know that there were once
rivers and ice sheets now are. They do this ice-sheets in the
because of the grandeur and beauty world? We
which they present, and also because know this
the history of the past conditions because of
may be read through what is the great
taking place to-day. amount of
The ice from some material
of the glaciers of which was
to-day is utilized
by man as an left when GRAVEL &
article of trade. the ice was
Men cut it into melted by SAND HILLS
blocks and LEFT BY the warmer
transport it to THE ICE
cities, where it weather. RIVER..
is sold to supLarge pieces
ply people with of rocks,
ice during the
su m m er which we
months. call bowlders, were left
When the strewn over the surface at this time.
ice river descends to the sea the weight Do you know of any bowlders in your school district ?
of the ice, together with the pressure In some cases the valleys were filled of the water underneath, causes great and the mountains completely buried by masses of ice to break off. These are this mate.
icebergs. rial. Some
They float of our
away, and plains and
are dan. prairie
gerous to land were
steamer's made in
and boats this way.
because of The soil of
their great the areas
bu lk. THIS ICE RIVER FLOWS TO THE SEA. formerly
(P. 117.) covered with ice is quite different from Describe each of the pictures. Note the great that of other sections.
chasms or gorges in the ice which make traveling
over the glaciers very dangerous. Visit sand hills, Many lakes lie in the depressions made clay beds, and bowlder-strewn surfaces. Learn all by the old ice rivers as they gouged their you can about them. Describe and sketch them.
Here is the picture of a lake. It lies On the next page is the picture of a in the lowest part of a hollow in the lake which lies in a basin in the lowland. land surface high up in the mountains. Tell how this lowland Jake basin differs from The entire hollow is a lake basin. the mountain lake basin. Trace its shore-line.
Tell what plants The lake is
are growing on its fed by the
shiore. What evstreams which
idences of life are
there? form from the rains and melt
On the next ing snow, and
page there are flow down the
pictures of inside slopes
ponds; one is of the basin.
in the mounThe land
tains, and one which borders
is in the lowthe water of
lands. a lake is a lake
Trace around shore. The
each. Trace the
slopes of each. shoreline is
What evidences the line where
of life are there the land slopes
in these pictures? under the wa
You see ter. The high
ponds are like er and lower
lakes in form, land of the
only they are lake shore
smaller. causes many
Α ιι irregularities A MOUNTAIN LAKE.
BY FEEDER CAPE in the shore-line. In places where
PONDS are the shores are high the land pro
fed by jects out into the water; in places
streams where the shore is low the water
and springs. flows over the land, making indenta
Some lakes tions of the lake into the land.
and some ponds If you could lo vk down on this lake you should
have only one
MAP OF A MOUNTAIN LAKE. see its true shape or map. Trace the shore-line
large feeder. of the lake pictures. Tell where there are projec- Lakes and ponds usually have OUTLETS tions and indentations. Model this lake-basin. Tell which part is occupied by the lake. Represent
which carry the water away from them to the streams which feed it.
lower land and to the sea.
The feeders are usually muddy. This All lakes and ponds of the world are is because they
filling up. carry a great
· We can find deal of soil.
old lake botThey carry
toms in almost much more
any locality. soil during
Observe the heavy rains or
pictures on the melting snows
next page. than at any
Both are fine other time.
illustrations of The dirt or soil
a lake basin is washed from
in the process
of filling. the mountain
You see vil sides as the
lages are streams de A LOWLAND LAKE.
built on the scend to the
mud plains. During flood-time the hollows occupied by the lakes and ponds are completely filled with water. The water often reaches far up on the shore. In the highland region the basin overflows at its lowest point and the water flows away to lower land. The
A MOUNTAIN POND. lake. This soil settles in the bottom of that part of the pond or lake which is nearest the entrance of the stream.
Streams continue to carry soil to the pond or lake until it is filled up. It first becomes swampy, and
A LOWLAND POND. then a solid, fertile plain. Such plains are usually drained by one or more water from the lake in the lowland streams.
spreads far out over the low-lying land.