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From 1938 to 1947, the United States Forest Service took thousands of aerial photographs of the state of Colorado. The hope was that these images would be used by agronomists, land use planners, farmers, and other groups...
The AeroFiles website is dedicated to providing information on the history of American Aviation for the past one hundred years. Information on civil, commercial and military aviation can be found on this site. The...
While Alfred Thayer Mahan may have been obsessed with the role of naval power in warfare, the 20th century saw the rise of air and space power in a way that might have surprised even Mahan himself. Persons with an...
This collection of approximately 4,500 photographs documents natural environments, ecologies, and plant communities in the United States at the end of the nineteenth and the beginning of the twentieth century. Produced...
In late 1969, Wisconsin Senator Gaylord Nelson hired Denis Hayes to organize a national teach-in day about the importance of protecting the environment for future generations. On April 22, 1970, the first Earth Day was...
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