FoodNet

Domestic science, principles and application

1914

Page 12

Presented as published in 1914. Historical recipes may not meet modern food-safety standards. Cook from the modern interpretation, not the original instructions.
Care of Brooms, Brushes, and Dust Cloths. — Brooms. — In using a broom alternate first one side and then the other, so that it wears evenly. Clean broom off after sweeping, making it ready for use again. Always hang broom up; do not allow it to rest on the bristles. The broom should be washed in good warm suds every week to keep it in good condition. Brushes. — Brushes should be cleaned well after each using. Later they may be washed in cold water, but great care must be taken not to wet the glue which fastens the back of the brush. Dry thoroughly. Dust cloths. — Wash dust cloths frequently in hot soap- suds, scald, rinse in clear water, and dry in the sun and air. Explain why this precaution is always necessary. LESSON 1 LIFE ESSENTIALS— AIR, WATER, FOOD. FURTHER WORKING DIRECTIONS Three things are essential to life: (1) air, (2) water, and (3) food. In addition, most forms of life need sunlight and a favorable temperature. AIR Air is the most immediate need of the body, since we can live but a few minutes without it. Composition of Air. — Pure air is composed mainly of two gases, oxygen and nitrogen, in the proportion of 1 part of oxygen to about four parts of nitrogen. A certain amount of water vapor in the air makes it easier to breathe. Impure air may contain, in addition to nitrogen and oxygen, harmful gases, dust, and other impurities. In dwellings the harmful gas is usually carbon dioxide, which is noticeable when the room is poorly ventilated. Sources of Carbon Dioxide Gas. — Carbon dioxide gas is formed by the union of carbon and oxygen in a process called oxidation. This takes place in — (1) All burning of carbon material. (2) Decaying vegetable and animal life. (3) The process of respiration. In the latter process the oxygen in the air passes through the thin walls of the lungs into the blood, which carries it to all parts of the body. The union of this oxygen with the carbon in the cell tissues forms carbon dioxide as a waste product, which in "turn is carried back by the blood to the lungs and given off. (15) 16 DOMESTIC SCIENCE Ventilation. — How may pure air be brought into a room and the impure air sent out? How is your home venti- lated? How is your school ventilated? The natural means of ventilation are doors, windows, cracks, and chimneys. Special ventilating systems, flues, etc., may be spoken of as the artificial means of ventilation. WATER Water ranks next to air as a supporter of life. Pure water is a liquid, clear, odorless, colorless, and almost taste- less. Composition. — Chemically pure water is composed of 1 part oxygen to 2 parts of hydrogen. The flavor of drink- ing water is due to the mineral salts and carbon dioxide gas dissolved in it. Sources. — (1) Rain. (2) Surface water, as from rivers, brooks, lakes, ponds. (3) Ground water, as from wells, open and artesian, and some springs. Uses. — ^Water has many uses. It enters into all plant and animal life. It constitutes about three-fourths of the weight of the body. (a) Uses in the body : — 1. It quenches thirst. 2. It aids in regulating the body temperature. 3. It aids digestion, since it forms a part of all the digestive secretions of the body, and acts as a solvent; that is, dissolves most substances and reduces them to a condi- tion to be of use to the body.