1. How may "catching" diseases be prevented? 2. What are disease germs, and how are they named? 3. How do disease germs grow? 4. Why should patients with the "diseases of childhood" be placed in quarantine. 5. What causes a cold? How should you take care of one? Why keep away from other people? 6. When and how did we find that diphtheria was due to germs? 7. Explain how "antitoxin" prevents it. 8. How much has the death rate in diphtheria been lowered? 9. Name the diseases for which we now have vaccines and antitoxins. How do we grow them? 10. Tell the story about Dr. Jenner and the milkmaids. 11. What good has his discovery done? 12. Explain why vaccination will cure as well as prevent smallpox. 13. What is quinine, and where does it get its name? 14. Who discovered the germ of malaria? Is it a plant or an animal? 15. What do we know about the connection between mosquitoes and malaria? 16. What is a quick way of killing the mosquito? 17. How does draining fields prevent malaria? Why is malaria not so common now as in pioneer days? 18. Why do we need disinfectants? Name some, and describe how they are used. 19. What is the best one in most cases? Why? In what ways may it be used? 20. How do the bacteria of the soil "feed" the green plants? 21. Explain why a crop of clover will enrich the soil. What other plants also do the same thing? 22. Name some other harmless bacteria. 23. Why ought one to wash the hands before eating? 24. Is it possible to kill all house flies? Why ought we to try to? How can it be done? 25. What do we find in dust? 26. What good does it do to sprinkle streets? 27. What is the best way to clean house? CHAPTER XXVII