CHAPTER XII.  HOW TO KEEP THE HEART AND BLOOD HEALTHY.—­Name some things likely to injure the heart or the blood.  What is the effect of violent exercise? of bad air? of bad food? of loss of sleep? of violent anger?  What can you say about clothing?  What is the effect of alcohol upon the blood? the heart? the bodily heat?  What is the effect of tobacco upon the heart? the pulse? the blood?  What is the effect of tea and coffee upon the heart?  What is a cold?  In a case of bleeding from a wound, how can you tell whether a vein or an artery is cut?  How would you stop the bleeding from an artery? from a vein?  How would you stop nose-bleed?

CHAPTER XIII.  WHY AND HOW WE BREATHE.—­What happens to a lighted candle if shut up in a small, close place? to a mouse?  Why is air so necessary for a burning candle and for animals?  How is the heat of our bodies produced?  Name the principal organs of breathing.  Describe each.  How do we use the lungs in breathing?  How much air will a man’s lungs hold?  How much air do we use with each breath?  What poisonous substance does the air which we breathe out contain?  Will a candle burn in air which has been breathed?  What happens to animals placed in such air?  What change takes place in the blood as it passes through the lungs?  How do plants purify the air?

CHAPTER XIV.  HOW TO KEEP THE LUNGS HEALTHY.—­What is the thing most necessary to preserve life?  Name some of the ways in which the blood becomes impure.  Why is bad-smelling air dangerous to health?  What are germs?  Why are some diseases “catching”?  Name some such diseases.  What should be done with a person who has a “catching” disease?  What is the effect of the breath upon the air?  How much air is poisoned and made unfit to breathe by each breath?  How much air do we spoil every minute? every hour?  How much pure air does each person need every minute? every hour?  How do we get fresh air into our houses?  Why are windows and doors not good means of ventilating in cold weather?  How should a room be ventilated?  How should we use the lungs in breathing?  What about the clothing in reference to the lungs?  Why is it injurious to breathe habitually through the mouth?  What is the effect of alcohol upon the lungs?  What is the effect of tobacco-using upon the throat and nose?

CHAPTER XV.  THE SKIN AND WHAT IT DOES.—­How many layers in the skin?  What is each called?  To what is the color of the skin due?  What glands are found in the true skin?  What are the nails and what is their purpose?  How does the hair grow?  Name the different uses of the skin?

CHAPTER XVI.  HOW TO TAKE CARE OF THE SKIN.—­What happened to the little boy who was covered with gold leaf?  Why did he die?  What is the effect of neglecting to keep the skin clean?  What is the effect of wearing too much clothing and living in rooms which are too warm?  How should the hair be cared for? the nails?  What is the effect of alcohol, tobacco, and other narcotics upon the skin?