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What is a magnet? What are the poles of a magnet?

What is a temporary magnet? - What is a magnetic field?
Is the earth a magnet? How find the earth's magnetic
poles?
Exercises and summary.

Electric magic. Are all electric charges alike? How does a

lightning rod protect a house? - Where does an electric cur-
rent come from? Can we make a magnet from a current?
How does a dry cell give a current? - Why are electric wires
covered? - Exercises and summary.

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What is an electromagnet? How do we ring an electric

bell? How can a telegraph wire carry a message?
How can
a current silverplate a spoon? — How does electricity produce
heat and light? How does a dynamo produce a current?
How does electricity produce motion? - Exercises and summary.

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Why can we see objects? How does sunlight travel?

How does a mirror change light? Why does an object have
a shadow? How does distance affect the brightness of light? -

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How do we get sunlight into the house? How have men

lighted their houses at night? How do kerosene lamps work?
How do we get light from gas? - How does a fuse box pro-
tect a house? - How are gas and electricity measured? - How
are gas and electric meters read? - What is the right way to use
light? What is indirect lighting? - Exercises and summary.

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an echo?

How do we hear? What causes

What is the difference between noise and tone?
What are the classes of musical instruments? - How does a
telephone carry sound? - Exercises and summary.

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pulleys help us? How do we use a wheel and axle?
use are the wedge and the screw? - Why do we oil a machine?
Exercises and summary.

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How does a sailboat use the wind? Why do kites fly?

Why do airplanes rise? - Why do windmills turn? - How has
man harnessed water? How does the sewing machine lighten

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work?

How does a

How is cream separated from milk?

vacuum cleaner work? - How can we wash clothing by elec-
tricity? How do gases cause motion? - How does an engine
run? What makes an automobile run? - Exercises and sum-
mary.

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How does man make use of plants? - Loes man eat grass?
What grasses do we use? How do corn and rice grow?
How do sugar cane and bamboo grow? Why is wheat flour
used for yeast bread? What are the legumes? - How do
legumes capture nitrogen? Why do we eat vegetables?
What fabrics do we get from plants? What is a fruit?
Exercises and summary.

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How many kinds of animals are there? - Have animals

helped, or hindered, man's progress?

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What are man's beasts

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of burden? What animals give us meat? Why is milk valu-
able? What is leather? What birds give us food? - Why
and how should we protect birds? — What fishes are used by
man? - What are insects like? - What insects give us food?
What are our insect enemies? How may flies and mosquitoes

be destroyed?

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- Exercises and summary.

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What organs digest our food? How does the mouth help

in digestion? What is the work of teeth? How do we
swallow? What is the structure of the stomach? - What
happens to food in the stomach? What are the intestines
like? What happens to food in the intestines? - What
should our diet be? Is alcohol a food? -- Exercises and sum-
mary.

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