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.
Having decided through these experiments on the process by which he would manufacture carbolic acid synthetically, Edison designed his first plant, gathered the building material and apparatus together and instructed his engineers to rush the construction as fast as possible. By working gangs of men twenty-four hours a day the plant was rapidly completed and on the eighteenth day after the work of construction was begun it commenced turning out carbolic acid. Within a month this plant was making more than a ton a day and gradually increased its capacity until, a few months afterward, it reached its maximum of six tons a day.
It soon became publicly known that Edison was manufacturing carbolic acid, and he was overwhelmed with offers to purchase the excess over his own requirements. The demand for carbolic acid became so great that he decided to erect a second plant. This was quickly constructed and its capacity, which was also six tons per day, was contracted for before the plant was fully completed. It is interesting to note that the army and navy departments of the United States were among the first to make long contracts with Edison for his carbolic acid, from which they made explosives that were badly needed.
We must digress here to show an emergency that had arisen during the early days of the first carbolicacid plant. There had come about a serious shortage of benzol, which is a basic material in the manufacture of synthetic carbolic acid. Benzol is a product derived from the gases arising from the destructive distillation of coal in coke ovens. At the time of which we are writing (beginning of 1915) there was only a comparatively small quantity of benzol produced in the United States.
Mr. Edison realized that without a continuous and liberal supply of benzol he would be unable to carry out his project of producing carbolic acid in large quantities. He had also been approached by various textile manufacturers to make aniline oil, which was essential to their continuance in business, and of which there was practically no supply in the country. Without it he could not make paraphenylenediamine. Benzol is also a basic material in making aniline oil.