Ralph Waldo EmersonApril 27, 1882: Ralph Waldo Emerson (at right) dies at age 79 in Concord, Mass. The lecturer, essayist and Unitarian minister's works include "Nature" in 1836. Emerson sells 500 copies of the book in six years, but he later becomes a wildly popular lecturer.

April 27, 1914: Former U.S. President Theodore Roosevelt completes a two-month trek through unexplored parts of the Amazon. The River of Doubt is renamed Rio Roosevelt in his honor.

April 27, 1935: In the midst of the Dust Bowl and massive dust storms rising off the farmlands of the Midwest, the U.S. Congress passes the Soil Conservation Act.

Photo: Wikimedia Commons

This feature is compiled by Peter Dykstra, an MNN contributor and publisher of Environmental Health News and The Daily Climate.