30. Show how life depends on repair and waste.
31. What is the difference between the decay of the teeth and the constant decay of the body?
32. Should biscuit and cake containing yellow spots of soda be eaten?
33. Tell how the body is composed of organs, how organs are made up of tissues, and how tissues consist of cells.
34. Why do we not need to drink three pints of water per day?
35. Why, during a pestilence, are those who use liquors as a beverage the first, and often the only victims?
36. What two secretions seem to have the same general use?
37. How may the digestive organs be strengthened?
38. Is the old rule, "after dinner sit awhile," a good one?
39. What would you do if you had taken laudanum by mistake? Paris Green? Sugar of lead? Oxalic acid? Phosphorus from matches? Ammonia? Corrosive sublimate? (See p. 265.)