Mountain Air.—The air of the mountains is pure. It is usually still, and seldom foggy. Being more rarefied than that of the low-lying valleys, it contains less oxygen in proportion to volume, but its lesser density gives to the oxygen greater activity.
The body loses heat less rapidly in rarefied atmospheres, so that there is probably less need of heat-production on the mountain than on the plain, combustion being less active. The rapid and great variations of temperature of the mountain regions stimulate the vital processes and contribute to the curative agencies of those altitudes.
Night Air.—There is a prevailing prejudice against night air. By many persons out-door air is shut out of the sleeping room as if it were pestilential. Analysis as well as experience shows that the most vitiated and unwholesome night air is that which has been breathed over and over again in a close sleeping apartment. Admit the outside air freely if you desire health. Guard against draughts, and use just enough bed covering for comfort.
Air of the School-Room.—A plentiful supply of pure air is desirable wherever there are people to breathe it. In no place is it more important than in the school-room. Confined for six hours each day during the period of life when the best health conditions are required for the proper growth of mind and body, the child thus robbed of the needed oxygen is wronged. The adult who voluntarily subjects himself once or twice a week for two hours to the poisonous atmosphere of church, lecture hall, or theatre, may experience a temporary headache, but is soon revived after reaching the fresh air. The child, ignorant of the wrong he is made to suffer, and incapable of providing better conditions, breathes the poisonous exhalations from fifty pairs of lungs, day after day, and thus has sown in his system the seeds of disease.
Illuminating Gas.—Many persons die every year by inhaling illuminating gas. People unacquainted with the use of gas fixtures often blow out the light instead of turning the key. A prevailing custom in some families is to keep the light burning low during the night. A variation of pressure in the pipes, or a sudden draught of air, extinguishes the slender flame, and gas escapes into the room, often with fatal results.
Leaky pipes or faulty fixtures may have the same effect. If the key be loose, tighten the screw that holds it in place. If there is a leak in the pipe or joint, which may be determined by applying a match, a gas-fitter should at once be summoned. Delay is dangerous and may prove fatal.
If a room be heavily charged with gas, get the windows and doors open as soon as possible. Do not go near with a light, lest an explosion follow. Naphtha and benzine are also highly explosive. When either is used to clean clothing, the work should be done in the open air, and never where the fumes may come in contact with the fire of stove or range, or with the flame of candle or lamp.
Gas burners, oil lamps, sperm candles, all forms of illuminants, consume the oxygen of a room and increase the carbonic acid. An oil lamp of ordinary dimensions gives off as much carbonic acid as an adult person. A man, seated in a room of moderate dimensions and using a good oil lamp, will require 6,000 cubic feet of fresh air every hour in order to keep the air from becoming vitiated beyond the point of wholesomeness. Gas from coal, coke, or charcoal fires is as dangerous as illuminating gas.