404 IDEAL HOME LIFE
ture being lowered at the same time. Distillation is an equally efficient method of obtaining absolutely pure water, but it is more troublesome than boiling where small quantities only are desired. At the present time the distillation of water in large quantities is an important industry, and is to be commended and encouraged when the question of expense is not important. Ice which is artificially made from distilled water is far safer than the natural supply for reasons which were given.
The general conclusion in regard to a water supply, whether public or private, may be, therefore, that it should be abundant, from twenty-five to fifty gallons per day for each individual, sufficient for drinking, washing, for the use of animals, and for keeping premises surrounding one's residence sufficiently moist; that it should be pure; that it should be kept in motion as much as possible (stagnation in metallic pipes, in cisterns or in pools often contaminates it), and that it should be without offensive taste or odor.
Air as a Tonic
If a salubrious climate, and a suitable soil, and a proper supply of water are indispensable requisites to health, certainly not less indispensable is a sufficient volume of pure air. From the moment a human being enters the world, when the lungs expand for the first time and give expression to it in a cry, till the last gasp of physical existence, there is one imperious requirement which must ever be satisfied, the requirement for air. It matters not what the condition of the individual may be, savage or sage, saint or sinner, pauper or millionaire, air he must have or die.
Air is a mixture, four of its parts being nitrogen and one oxygen, the latter being the essential element, and being taken into the blood in connection with the process of breathing. The two gases are so loosely combined that the oxygen is easily separated from the nitrogen. Air also contains argon, watery vapor, carbonic dioxide, dust, smoke, and various other impurities. The higher we ascend, the rarer and purer the air; and the purer the air, the more the mucous membrane of the