Rachel Carson, American Marine Biologist
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Gifford Pinchot American
NPS Photo
John Muir, Scottish-american Naturalist
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John Muir, Naturalist
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Mckinley-roosevelt Campaign Poster, 1900
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John Burroughs, American Naturalist #1
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Gifford Pinchot, American
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Bernard De Jussieu, French Naturalist
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Bernard De Jussieu, French Naturalist #1
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John Burroughs, American Naturalist
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Gifford Pinchot American #2
NPS Photo
President Roosevelt And Gifford Pinchot
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John Burroughs, American Naturalist
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President Theodore Roosevelt Riding
NPS Photo
President Theodore Roosevelt
NPS Photo
Young Theodore Roosevelt
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