At the beginning of the twentieth century there is, strictly speaking, no frontier to the United States. At the beginning of the nineteenth century, the larger part of the country was frontier. In any portion of the country to-day, in the remotest villages and hamlets, on the enormous farms of the Dakotas or the vast ranches of California, one is certain to find some, if not many, of the modern appliances of civilization such as were not dreamed of...