CHAPTER XIV
FORM IV: SENIOR GRADE (Continued)
HOUSEHOLD SANITATION
As the principles of sanitation are based on a knowledge of bacteria, the facts concerning these microscopic plants, which were taught in the lesson on the "Preservation of Food", have only to be reviewed and extended.
The following topics should he quickly reviewed:
1. Description of bacteria
2. Occurrence of bacteria
3. Favourable conditions for bacteria
4. Multiplication of bacteria
5. Useful bacteria
6. Harmful bacteria.
It is with the harmful bacteria that our lesson on sanitation deals. The pupils already know that some kinds belonging to this class cause the decay of food, and now they are ready to be told that other harmful kinds of microscopic plants gain entrance to our bodies and cause disease. Concerning these, the following outline of facts should be taken:
1. MEANS OF BACTERIA ENTERING THE BODY
(1) Through the respiratory organs
(2) Through the digestive tract