The provinces in which mechanical architecture has been genuinely successful are those in which there have been no conventional precedents, and in which the structure has achieved a sense of absolute form by following sympathetically the limitations of material and function. Just as the bridge summed up what was best in early industrialism, so the modern subway station, the modern lunch room, the modern factory, and its educational counterpart, the modern school, have often been cast in molds which would make them conspicuous esthetic achievements. In the Aristotelian sense, every purpose contains an inherent form; and it is only natural that a factory or lunchroom or grain elevator, intelligently conceived, should become a structure quite different in every aspect from the precedents that are upheld in the schools. It would be a piece of brash esthetic bigotry to deny the esthetic values that derive from machinery: the clean surfaces, the hard lines, the calibrated perfection that the machine has made possible carry with them a beauty quite different from that of handicraft--but often it is a beauty. Our new sensitiveness to the forms of useful objects and purely utilitarian structures is an excellent sign; and it is not surprising that this sensitiveness has arisen first among artists. Many of our power-plants are majestic; many of our modern factories are clean and lithe and smart, designed with unerring logic and skill. Put alongside buildings in which the architect has glorified his own idiosyncrasy or pandered to the ritual of conspicuous waste, our industrial plants at least have honesty and sincerity and an inner harmony of form and function. There is nothing peculiar to machine-technology in these virtues, however, for the modern factory shares them with the old New England mill, the modern grain elevator with the Pennsylvania barn, the steamship with the clipper, and the airplane hangar with the castle. The error with regard to these new forms of building is the attempt to universalize the mere process or form, instead of attempting to universalize the scientific spirit in which they have been conceived. The design for a dwelling-house which ignores everything but the physical necessities of the occupants is the product of a limited conception of science which stops short at physics and mechanics, and neglects biology, psychology, and sociology. If it was bad esthetics to design steel frames decorated with iron cornucopias and flowers, it is equally bad esthetics to design homes as if babies were hatched from incubators, and as if wheels, rather than love and hunger, made the world go round. During the first movement of industrialism it was the pathetic fallacy that crippled and warped the new achievements of technology; today we are beset by the plutonic fallacy, which turns all living things it touches into metal.