Ammons, A. R. (1926-2001), was an American poet whose verse explores natural processes, from the cosmic to the microscopic. Trained in science, Ammons brought to his poetry a subtle understanding of how organisms and events interact in nature to produce endless complexity. In one poem, "Cascadilla Falls," he contemplated a single stone while trying to imagine all the forces that affect it: gravity, the spinning of the earth and its orbit around the sun, and the movement of the solar system and galaxy.