Air, water and food from a sanitary standpoint / by Ellen H. Richards and Alpheus G. Woodman.

  • Ellen Swallow Richards
Date:
1900
Catalogue details

Licence: Public Domain Mark

Credit: Air, water and food from a sanitary standpoint / by Ellen H. Richards and Alpheus G. Woodman. Source: Wellcome Collection.

Provider: This material has been provided by the Harvey Cushing/John Hay Whitney Medical Library at Yale University, through the Medical Heritage Library. The original may be consulted at the Harvey Cushing/John Hay Whitney Medical Library at Yale University.

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    that it should not decompose too much soap. Manufactur- ing interests require that it should not give too much scale to boilers; for agriculture there should not be too much alkali. From the nature of things, no one family or city can have sole control of a given body of water. Those on the high- lands may have the first use of the water, which then perco- lates to a lower level and is used by the people on the slopes over and over before it reaches the sea to start again on its cycle of vapor, cloud and rain, brook and river. Al- though receiving impurities each time, there are many beneficent influences at work to overcome the evils resulting from this repeated use. That which is dissolved from one portion of earth may be deposited on another. As the plant is the scavenger of the air, withdrawing the carbon dioxide with which it would otherwise become loaded, so the water has also its plant life, purifying it and withdrawing that which would otherwise soon render it unfit for any use. Pure water is found only in the chemical laboratory; the most that can be hoped for is that human beings may secure for themselves water which is safe to drink, which will not impair the efficiency of the human machine. The importance of the third essential for human life, food, and the close interdependence of all three, may be clearly shown. Of little use is it to provide pure air and clean water if the substances eaten are not? capable of com- bining with the oxygen of the air or of being dissolved in the water or the digestive juices; of less use still is it to par- take of substances which act as irritants and poisons on the tissues which they should nourish, and thus prevent healthful metabolism and respiratory exchange. And yet a large majority of those who have acquired some notion of the meaning and importance of pure air and
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