To the above complete and convincingly apt arguments and statements of fact, we do not care to add any thing. All that we desire is to direct public attention to the admirable qualities of this Earth System, and to suggest that, at least for those living in the country away from the many conveniences of city life, great water power, and mechanical assistance, the use of it will conduce largely to the economy of families, the health of neighborhoods, and the increasing fertility and prosperity of the country round about.
XXXVI.
WARMING AND VENTILATION
There is no department of science, as applied to practical matters, which has so often baffled experimenters as the healthful mode of warming and ventilating houses. The British nation spent over a million on the House of Parliament for this end, and failed. Our own government has spent half a million on the Capitol, with worse failure; and now it is proposed to spend a million more. The reason is, that the old open fireplace has been supplanted by less expensive modes of heating, destructive to health; and science has but just begun experiments to secure a remedy for the evil.
The open fire warms the person, the walls, the floors and the furniture by radiation, and these, together with the fire, warm the air by convection. For the air resting on the heated surfaces is warmed by convection, rises and gives place to cooler particles, causing a constant heating of its particles by movement. Thus in a room with an open fire, the person is warmed in part by radiation from the fire and the surrounding walls and furniture, and in part by the warm air surrounding the body.
In regard to the warmth of air, the thermometer is not an exact index of its temperature. For all bodies are constantly radiating their heat to cooler adjacent surfaces until all come to the same temperature. This being so, the thermometer is radiating its heat to walls and surrounding objects, in addition to what is subtracted by the air that surrounds it, and thus the air is really several degrees warmer than the thermometer indicates. A room at 70 degrees by the thermometer is usually filled with air five or more degrees warmer than this.
Now, the cold air is denser than warm, and therefore contains more oxygen. Consequently, the cooler the air inspired, the larger the supply of oxygen and of the vitality and vigor which it imparts. Thus, the great problem for economy of health is to warm the person as much as possible by radiated heat, and supply the lungs with cool air. For when we breathe air at from 16 to 20 degrees, we take double the amount of oxygen that we do when we inhale it at 80 to 90 degrees, and consequently can do double the amount of muscle and brain work.
Warming by an open fire is nearest to the natural mode of the Creator, who heats the earth and its furniture by the great central fire of heaven, and sends cool breezes for our lungs. But open fires involve great destruction of fuel and expenditure of money, and in consequence economic methods have been introduced to the great destruction of health and life.
Of these methods, the most popular is that by which radiated heat is banished, and all warmth is gained by introducing heated air. This is the method employed in our national Capitol, where both warming and ventilation are attempted by means of fans worked by steam, which force in the heated air. This is an expensive mode, used only for large establishments, and its entire failure at our capitol will probably prevent in future any very extensive use of it.
But the most common mode of warming is by heated air introduced from a furnace. The chief objection to this is the loss of all radiated heat, and the consequent necessity of breathing air which is debilitating both from its heat and also from being usually deprived of the requisite moisture provided by the Creator in all out-door air. Another objection is the fact that it is important to health to preserve an equal circulation of the blood, and the greatest impediment to this is a mode of heating which keeps the head in warmer air than the feet. This is especially deleterious in an age and country where active brains are constantly drawing blood from the extremities to the head. All furnace-heated rooms have coldest air at the feet, and warmest around the head. It is also rarely the case that furnace-heated houses have proper arrangements for carrying off the vitiated air.