The machine age came to the Western world two centuries ago, but today in many of the more remote parts of southern and eastern Europe the only power-driven machinery is that placed in motion by watermills whose origin goes back some two thousand years to the eastern Mediterranean basin. These pre-industrial water-mills, supplemented in some regions by others propelled by wind, are numbered by the thousands and possibly by the tens of thousands. By far the greater number are gristmills, engaged at appropriate seasons in the reduction of the farmer's grain into meal, often ticking on unattended much of the time during the daytime hours. Much smaller numbers of water-mills are employed in the fulling of hand-loomed cloth, the raising of water for irrigation, the crushing of olives, and, much less frequently, the carding of wool and sawing of lumber. To observe these simple country mills in operation is to be carried back a century and more in our own experience to a time when few rural communities in the United States lacked the basic equipment of gristmill and sawmill and when fulling, carding, oil, and bark mills played their lesser but important roles. In this early rural America, as in some of the less advanced regions of Europe today from the Iberian peninsula to the Balkans, these small and mechanically inefficient but very effective mills brought a welcome relief to men and women burdened with the endless drudgery of subsistence farming in what was mainly a pre-market as well as a pre-industrial economy. In the United States, the federal Census of 1840 reported nearly 60,000 of the three principal rural water-mills: gristmills, sawmills, and fulling mills, of which some 24,000 were gristmills and flour-mills, or twofifths of the total number.1 In Portugal today, with slightly more than DR. HUNTER, professor of history at American University until his retirement in 1966, is the author of Steamboats on the Western Rivers: An Economic and Technological History. He is currently preparing a history of industrial power in the United States.