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Conservation in the Progressive Era
Conservation by Sanitation

While most conservationists in the early 1900s spoke and wrote about natural resources such as the land, trees, and water, Ellen Henrietta Swallow Richards, a chemist and faculty member at the Massachusetts Institute of Technology, wrote about the dangers of air and water pollution. Describing herself as a "human ecologist," Ms. Richards sought to apply the principles of the conservation movement directly to human life through the improvement of the urban environment. In the excerpts that follow, she discusses air pollution. Why does she think "outdoor" air is preferable to "indoor" air? When "outdoor" air gets bad, what does she think city or state government ought to do? Can you think of any actions that city and/or state governments take to help curb air pollution today?

View the entire document from which this excerpt was taken, from Evolution of the Conservation Movement, 1850-1920. Use your browser's Back Button to return to this point.

Man has learned very slowly the condition of his own safe living. Of the three essentials, air, food, water, the air he breathes and is surrounded by, being invisible, is the least known of all.

Before the time of Galen, B. C. 200, air was supposed to be carried in the body by the arteries. It was about 1553 before Servetus in his search for the connection between the breath of life and the soul discovered the circulation of air through the lungs and that the bright color of arterial blood was taken on there. He was burned at the stake for his unholy work.

In 1668 the real office of air was discovered by Mayow but was lost sight of for many years. . . .

It is not to be wondered at that to most persons the word air means very little. They are so used to taking air like other cosmical phenomena, "as it comes," that they are not conscious of the effect of different qualities of air upon their brains and bodies. It is only when they themselves are smitten with the more spectacular forms of disease caused by bad air, such as tuberculosis, and when a physician in whom they have confidence assures them that their only change for life is to live out of doors, that they begin to realize that the indoor air they have been taking must have been bad.

To account for the effects of outdoor air, one theory after another has been propounded-such as ozone, aromatic essence from certain trees, dryness, dampness, rarity, density, freedom from earth exhalations, etc. It is one of the great advances of modern science to have discovered that just simple ordinary outdoor air is a most valuable health resource; that a balcony on a city street is a thousand times better than a room in a house closed for fear of drafts, curtained for fear of fading the furniture, and lighted by a lamp. . . .

Man cannot control the temperature of outside air, the amount of water it contains, or its pressure; to some extent the amount of impurity it contains may be controlled. Oiled streets and dustless pavements may be insisted on. The city should carry out its duty towards its citizens in the matter of clean air by keeping its streets free from dust and dirt-such as the grit from abrasions of the surface, ground-up dropping, iron dust from wheels and carts, bacteria from dried sputum, etc.- which would otherwise be lifted by the wind.

For example, the State might be visualized as immersed in a great sea. Here and there a city is sending up great clouds of dust, smoke, and foreign gases which may be likened to city sewage rising from points at the bottom of the clear sea. Between these great sources of pollution run connecting roads, boulevards, railways, each sending out all along its sinuous course dense currents of waste and contaminated air. Along these lines of pollution appear houses and factories, often emitting foul air themselves and completely surrounded by dense clouds of air sewage, only appearing to the view as sudden gusts blow the mass away. This sort of visualization will lead to the conclusion that even outside air is bad in the vicinity of cities. It is, but it is better for the most part than indoor air. A man living all his life in the open is said to be able to smell the bad air of a city the moment he steps inside its gates. We who live and smother in our own and our neighbor's exhalations grow accustomed to the stench.
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View the entire document from which this excerpt was taken, from Evolution of the Conservation Movement, 1850-1920. Use your browser's Back Button to return to this point.