Domestic science (Johnson, for schools and homes)

The importance of pure air for respira- tion is emphasized by the fact that in strangling, drowning, choking, or any other process of asphyxiation, the person dies by reasons; first, that the supply of oxygen is stopped; second, that the carbonic acid gas can not escape from the blood. The person becomes black in the face, the veins become distended, and insensibility and death follow, if proper aid is not given. In brief, the person suffers from oxggen starva- tion and carbonic acid poisoning, at one and the same time. Since the common use of gas for cooking, heating, and illuminating purposes, asphyxiation is quite frequent; but one need not suffer asphyxiation to feel the evil effects of bad air. Asphyxiation takes place whenever the proportion of carbonic acid in the inspired air reaches ten per cent.; the oxygen being diminished in like proportion. Kow this con- dition is caused, makes no difference to the sufferer. It may be caused by shutting out fresh air, or by increasing the num- APPENDIX 107 ber of persons breathing the same air; or by suffering com- bustion, in any form, to use up the oxygen in the air. The deprivation of oxygen and the increase, correspond- ingly, of carbonic acid, is injurious long before the point of asphyxiation is reached. Nervous uneasiness, clouded thoughts, headaches, etc., occur when less than one per cent, of the oxygen of the air is replaced by any ether matters; and the continuation of the respiration of such air lowers the tone of the entire system and leaves it susceptible to disease. To be supplied with respiratory air fairly pure, each adult man should have at least 800 cubic feet of space by himself; and that space should be freely accessible to currents of pure, fresh air, by openings, direct or indirect, to the outer air; a current of from 1200 to 2000 cubic feet of fresh air per hour, would conserve the purposes of health and longevity much better. School buildings, churches, and other public auditori- ums are, at the present day, planned and constructed with some considerable regard to the amount of "air space" need- ed, and to methods of ventilation; but for reasons best known to the "care-takers" of such buildings, in general, the great audiences sit in such places and inhale air hot and "stuffy" from its burden of disease germs, carbonic acid gas, and unhealthful vapors, respired again and again by each member of the audience. Much less attention is given to the construction of the modern home, than to that of the modern auditorium. It seeming to be granted that the daily dwellers will properly ventilate their dwellings; but this judg- ment is too frequently in error. Sleeping rooms, especially, should receive their due proportion of properly oxygenated air, at all times; but these rooms have, on an average, the foulest air in the dwelling house; and it is, doubtless, true that many of the ailments of childhood, which leave the system in a weakened and de- pleted condition through life, are nursed and developed in these sleeping rooms, by foul air. Mothers fail to under- stand that sunshine, rain, and pure out-door air are as neces- 108 DOMESTIC SCIENCE