| George Perkins Marsh delivered an address before the Agricultural Society of Rutland County, Vermont, on this date in 1847. Marsh had worn many hats over his lifetime: lawyer, journalist, sheep farmer, mill owner, linguistics scholar, and diplomat. He designed the Washington Monument and co-founded the Smithsonian Institution. But it was in his role as United States senator that he addressed the Agricultural Society. He was the first person to publicly raise the issue of manmade climate change, and his speech helped spark the conservation movement. In his speech, Marsh said: "Man cannot at his pleasure command the rain and the sunshine, the wind and frost and snow, yet it is certain that climate itself has in many instances been gradually changed and ameliorated or deteriorated by human action. The draining of swamps and the clearing of forests perceptibly effect the evaporation from the earth [...] The same causes modify the electrical condition of the atmosphere and the power of the surface to reflect, absorb and radiate the rays of the sun, and consequently influence the distribution of light and heat, and the force and direction of the winds. Within narrow limits too, domestic fires and artificial structures create and diffuse increased warmth, to an extent that may effect vegetation." He was talking about concepts familiar to us now as the urban heat island effect and the greenhouse effect. As a result of his speech, Marsh went on to publish a book titled Man and Nature: or, Physical Geography as Modified by Human Action (1864). "[M]an is everywhere a disturbing agent," Marsh wrote. "Wherever he plants his foot, the harmonies of nature are turned to discords. The proportions and accommodations which insured the stability of existing arrangements are overthrown. Indigenous vegetable and animal species are extirpated, and supplanted by others of foreign origin, spontaneous production is forbidden or restricted, and the face of the earth is either laid bare or covered with a new and reluctant growth of vegetable forms, and with alien tribes of animal life." |
--From The Writers' Almanac, September 30, 2015. 
