All sources of energy upon which industry depends are wasted when they are employed; and industry is expending them at a continually increasing rate. Already coal has been largely replaced by oil, and oil is being used up so fast that East and West alike conceive it necessary to their own prosperity to destroy the industry of the other. And what is true of oil is equally true of other natural resources. Every day, many square miles of forest are turned into newspaper, but there is no known process by which newspaper can be turned into forest. You will say that this need not worry us, since newspapers will be replaced by radio, but radio requires electricity, electricity requires power, and power depends upon raw materials.