(3) Those coming through cuts, etc.--Skin diseases like ringworm, blood poisoning, lockjaw (tetanus). [Illustration: Sink and sewer connection T--Trap. W--Waste Pipe. H.D.--House drain. S.--Sewer.] If housekeepers do not exercise care, these disease-producing bacteria may enter the home, and finding there all the conditions which they require, they will multiply, and become a menace to the family. 3. METHODS OF SANITATION Since bacteria are too small to be seen, it is very hard to deal with them. The housekeeper has the following ways of protecting the household: (1) By having all drain pipes trapped: (2) By keeping the house free from lodging places for bacteria: (_a_) Keep the house clean and free of dust. (_b_) Wash garbage pails and sinks daily and scald them and drain pipes at least once a week. (_c_) Keep the refrigerators, cupboards, and receptacles for food clean, and allow no spoiled food to remain in them. (_d_) Wash and sterilize the soiled clothing once a week. (_e_) Keep the cellar well aired and clean; allow no decaying material to remain in it. (_f_) Keep the door-yards clean; allow no scraps of food, cleaning water, or sweepings to be thrown near the house. (3) By keeping the supply of food from disease-producing bacteria: (_a_) Use screens to keep out flies, which transfer bacteria from their bodies to food. (_b_) Wash fresh fruit and vegetables before using. (_c_) Boil for twenty minutes water of doubtful purity. (4) By keeping the bodies of the family strong and healthy, so that if bacteria gain an entrance they will be resisted and overcome: (_a_) Provide well-balanced, nutritious food. (_b_) Supply suitable clothing to protect the body. (_c_) See that there is an abundant supply of fresh air, night and day. 4. DISPOSAL OF WASTE IN VILLAGES AND RURAL DISTRICTS (1) Burn all combustible material. (2) Bury tins, broken dishes, etc. (3) Feed refuse food to animals or empty it into a pit dug for the purpose, and cover with a layer of earth from time to time. (4) Throw slop water at a distance from the house and well, and plant stalky growths like sunflowers, which absorb the waste. 5. METHODS OF DISINFECTING Where bacterial disease is known to exist, the utmost care should be taken to subject everything that has come in contact with the patient to a process which will kill the disease-producing plants. Only two ways of doing this are known: