What is a temporary magnet? — What is a magnetic field? - Is the earth a magnet? 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. Why are electric wires What is an electromagnet? How do we ring an electric bell? How can a telegraph wire carry a message? How can Why can we see objects? How does sunlight travel? How does a mirror change light? - Why does an object have Can light be turned out of its course? - - How does a burning glass work? - How does light form an image? How does a camera work? — What is the color of sunlight? — What is a How do we get sunlight into the house? lighted their houses at night? How do kerosene lamps work? How do we get light from gas? What causes a sound? How do we hear? What causes an echo? - get from machines? - Is a teeter a machine? How many ma- use are the wedge and the screw? - Why do we oil a machine? Why do windmills turn? How has man harnessed water? - How does the sewing machine lighten - work? How is cream separated from milk? - How does a run? mary. - seeds begin growing? What parts has a plant? — How do What are leaves like? What are leaves made of? What is the work of leaves? - What grasses do we use? - How do corn and rice grow? What is a fruit? How are trees our friends? How does a tree get its shape? What is the inside of a tree like? What are sapwood and of burden? - What animals give us meat? - Why is milk valu- - be destroyed? - Exercises and summary. - What is the plan of the body? What are living cells like? What are cells made of? What are bones like? - - How do bones grow? - Why do we have joints? What is the skeleton. like? How do our muscles work? What is the use of ten- - What organs digest our food? How does the mouth help in digestion? - What is the work of teeth? How do we What is the use of blood? What are red corpuscles for? What is the work of white corpuscles? - How is bleeding stopped? - How does the heart pump the blood? - How do arteries differ from veins? Does an artery bleed like a vein? What are capillaries? How does food get to the cells? How does the blood get rid of cell wastes? Exercises and sum- How do hair and nails grow? -- What is the work the brain? - What is the brain like? - What is the spinal - What has science taught us? How can science help a com- |