Water is considered pure from the standpoint of health when it is free from pollution, color, odor, poisonous salts, and turbidity. Clear, sparkling water is not necessarily pure however. The purity of water can be determined only by analysis.

In most states the public water supply of cities and towns is inspected regularly and the water is examined, so that the people may be protected from danger of infection. When the water used in a household is obtained from a well or private water supply, an analysis of it should be made.

All wells should be carefully constructed and covered, so that there may be no danger of pollution from surface drainage. Privy vaults should not be near the well or so located that there will be drainage from them to a well; otherwise the germs of typhoid and other diseases may find their way to it through the ground and become a source of danger to the persons using the water. As an extra precaution all discharges from persons who have tuberculosis, cholera, dysentery, or typhoid fever should be effectively disinfected before they are emptied into a privy vault or into a flush closet.

Purification of water. If the purity of the water is doubted, it should be boiled for five or ten minutes in a clean, covered kettle. This renders it safe. The flat taste which often results from the boiling may be remedied by shaking the water in a bottle or pouring it from one clean pitcher to another or by simply exposing it to the air overnight. Water should be kept cool, and should be protected from dust.

Household filters. The domestic filter is of little value. It will remove visible particles of matter, but will have very little effect upon bacteria. If such filters are used, they should be carefully and intelligently cleaned several times a day.

Care and arrangement of rooms. All the rooms in the house should be well ventilated and kept scrupulously clean. The windows should be entirely screened in order that they may be opened at both top and bottom. The screens should be put on in the spring before the flies and mosquitoes appear and should not be removed until all danger from them is past. Screens should be brushed frequently.

Dust and dusting. Dust is brought into the home on shoes and clothing, and is blown in from the outside. Dust must be kept under control by the use of a vacuum cleaner, a carpet sweeper, or a damp broom, and by good ventilation. Children should not be allowed to remain in rooms that are being swept, for dust causes an irritation of the eyes, nose, and throat and also is frequently a carrier of disease germs. The dusting of furniture should be done with a damp cloth. This will wipe off the dust and not stir it up into the air where it will be inhaled or will settle again. A feather duster should not be used. Dampened dusters may be prepared in the following way: spread the dusters out smoothly on a towel that has been wrung out of hot water, roll, and let them lie for half an hour before using.

The cellar. The cellar should extend under the entire house. If there is no cellar, the space under the floor should be well ventilated. There should be windows on at least two sides of the cellar to give ventilation and light, and the windows should be well screened. The cellar requires constant care and should be kept not only dry but clean and free from rubbish and substances that decay or absorb and hold moisture.

Care of food. Young people should learn to care for food in the home. Food should be fresh, clean, and wholesome. It should be protected from dust and handled only with clean hands. The development of bacteria may be prevented by keeping the food cold and clean. Fruits should be washed before being used. The outer covering of berries is easily bruised, and such fruits are frequently contaminated by dust and flies. Fruit should be full-grown but not over-ripe when eaten. Vegetables such as lettuce, celery, and radishes, that are eaten uncooked, should be thoroughly washed and rinsed in several waters.

Care of garbage. Garbage consists chiefly of the refuse matter from the kitchen. It should be kept in a clean metal can with a tight-fitting cover, since it will attract flies, rats, and other vermin. It is important that the can be frequently emptied and cleaned. Be careful that broken glass, broken dishes, nails, tacks, or old papers are not mixed with the kitchen refuse. Have a separate can or barrel for ashes and all glass and metal rubbish. The fair criterion of good housekeeping is the amount of garbage. A large amount of garbage means carelessness and waste in the kitchen.