In summer 1904, Henry Adams made what has undoubtedly become the most discussed visit to a world's fair in the annals of American letters. Adams, now the reigning elder of America's most distinguished Brahmin families, had recently returned from a long sojourn in Europe. While there he had indulged his fascination with medieval culture, in part by making a thorough tour of the French Gothic cathedrals. Now Adams left Washington for St. Louis to observe the vast spectacle of the Louisiana Purchase Exposition, which had been organized in commemoration of Thomas Jefferson's masterful negotiations with the French a century before. Riding the rails back to the East, Adams conceived what has come to serve as the touchstone of his memoirs, a chapter comparing the enthralling power exerted by the image of the Virgin Mary over medieval society with the almost mystical enchantment of the dynamo in modern American affairs. For Adams, the self-regenerating dynamo, which drew its own power back into itself in order to distribute still greater power to the vast array of lights and machines of the fair, served as an almost ideal icon for the capacity of modern society to organize itself around the single concept of productive efficiency, until society itself seemed to function as a giant machine.