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CHAPTER IX

More About Heat

Are heat and temperature the same? Can heat be

measured ? Is heat needed to melt ice? How does the

body keep its heat? — Why does perspiration cool the body?

Exercises.

CHAPTER X

Weather

What is the weather? Of what is the atmosphere com-

posed ? What causes dew and frost? - How are clouds
formed ? Why do we have rain, snow, and hail? What
is rainfall? What are the winds? - What causes our
great storms? — What is the weather service ? - - Exercises.

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CHAPTER XI

The Heavenly Bodies .

What is the earth like? What is the sky? Why do

the heavenly bodies rise and set? What is the path of a
star across the sky? What are some star groups ?
How far away are the stars ? Why are some heavenly
bodies wanderers ? · What is the sun like? What is the
solar system? Our neighbor, the moon. - What are
comets and meteors ? - Exercises.

CHAPTER XII

Force and Energy

What holds the solar system together? — Why does a

body have weight? In what direction does the earth pull ?

What is the density of water? Why does a body float?
Can you stand an egg on end ? Can a body move itself?

Why does a pendulum swing? — What is a force ?
When has a body energy? — Why do objects fly from the
center? — Why do planets revolve around the sun?

How can

CHAPTER XIII

Substances.

What is a substance ? Can substances be changed ?
Can water be changed ? What is an element?
we prepare hydrogen? What is hydrogen like? - What
is formed when hydrogen burns ? Do our fuels contain
hydrogen? — Is salt an element? What is sulphur like?

What is phosphorus like? What is a match? — Ex-

ercises.

CHAPTER XIV

Water .

Where is water found ? What is water like? How does

water boil? – How is ice made? How is ice cream frozen?

- How do bodies of water affect climate? How does

water change the earth's surface? Exercises.

Rocks and Soil

What is the earth's crust? What are the classes of

rocks? How are stratified rocks formed ?

What are
fossils ? - How are unstratified rocks formed ? What is
weathering ? — How do plants cause weathering ?

How
does the air aid weathering? How do water and ice cause

CHAPTER XXI

The Cooking and Baking of Foods

Why do we cook food ? Why are foods cooked in boil-

ing water? What is broiling ? · How do we fry foods?

What is the baking of foods? Why is baking powder used ?

- What is yeast? How does yeast act in making bread ?

- Exercises.

CHAPTER XXII

The Preserving of Foods

How do we can and preserve foods? How does drying

preserve food ?

How is meat smoked ? - What are salting
and pickling? How does sugar preserve food ? What
are the principles of canning ? What are the methods of
canning? — Does canning pay? - Canning as a factory
industry. Do preservatives harm food ? — Exercises.

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