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What is a temporary magnet? — What is a magnetic field?
How find the earth's magnetic

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Is the earth a magnet?
poles? - Exercises and summary.

Electric magic. Are all electric charges alike? -

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?

covered? Exercises and summary.

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Why are electric wires

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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?

lighted their houses at night?

How do kerosene lamps work?
How does a fuse box pro-

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How do we get light from gas?
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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What causes a sound? How do we hear? What causes

an echo?
- 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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What advantage do we

get from machines? - Is a teeter a machine? How many ma-
chines do we use? How does a lever help us? - How do
pulleys help us? How do we use a wheel and axle? Of what

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use are the wedge and the screw? - Why do we oil a machine?
Exercises and summary.

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Why do windmills turn? How has

man harnessed water? - How does the sewing machine lighten

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

run?

mary.

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seeds begin growing?

What parts has a plant? — How do

What are leaves like? What are
How does a

leaves made of? What is the work of leaves?
plant climb? What are stems and buds for? - What is the
work of roots? - Why do plants have flowers? - How are seeds
formed and scattered? What are the lower plants like?
Are wild flowers worth preserving? Exercises and summary.

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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?

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What is a fruit?

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How are trees our friends? How does a tree get its shape?

What is the inside of a tree like? What are sapwood and
heartwood? How are trees cut into lumber?
What are
the uses of wood? How is paper made? - What are the

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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

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be destroyed? - 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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