With the shattering of the world's peace by the great conflict which commenced on July 28, 1914, there came a universal disturbance of industrial conditions. The Edison industries were not exempt. Edison's activities during the years of the war were of the same intensely vigorous and energetic nature so characteristic of him throughout his busy life. His work during this period is divisible into two distinct sections: first, the working out of processes and the design and construction of nine chemical and two benzol plants to supply chemicals and materials greatly needed by our country; and, second, his war work for the United States government. We will discuss these in the above order. For many years before the war America had been a large importer of raw materials and manufactured products from England, Germany, and other European countries. Among these may be mentioned potash, dyes, carbolic acid, aniline oil, and other coal-tar products. After hostilities began the activities of the Allied fleets prevented all exportations by Germany and the Central Powers. On the other hand, England and her allies placed embargoes on the exportation from their countries of all materials and products which could be used for food or munitions of war. Thus there suddenly came a great embarrassment to numerous American industries. By reason of our continued importation for many years our country had become dependent upon Europe for supplies of various products and had made practically no provision for the manufacture of these products within our own borders. Inasmuch as our narrative concerns Edison and his work, we shall not attempt to name all the industries thus affected, but will confine ourselves to a mention of the items relating to his own needs and of those which he promptly took steps to produce for the relief of many industries and for the general good of the country. These items were carbolic acid, aniline oil, myrbane, aniline salts, acetanilid, para-nitro-acetanilid, paraphenylenediamine, para-amidophenol, benzidine, benzol, toluol, xylol, solvent naphtha, and naphthaline flakes. Edison's principal requirements were potash for his storage battery and carbolic acid and paraphenylenediamine for use in the manufacture of disc phonograph records. After a great deal of experimenting he found that caustic soda could be used in his storage battery and therefore employed it until new supplies of potash were obtainable. Carbolic acid and paraphenylenediamine had been previously imported from England and Germany and as there was practically none produced in the United States and no possibility of substituting other products Edison realized that he would be compelled to manufacture them himself, as the source of supply was cut off. He, therefore, as usual, gathered together all available literature and plunged into a study of manufacturing processes and quickly set his chemists to work on various lines of experiment.