Two influences that are continually upsetting normal price relationships are inventions and chemical discoveries. Historians still speak in awed tones of the changes brought about by the Industrial Revolution of the eighteenth century. Future students will probably point out that developments of the early twentieth century are of even greater significance. The development of the truck and the aeroplane have revolutionized railroad rates. Discovery of coal-tar dyes threatened the prosperity of a million-acre indigo industry in India, and an even greater upheaval will result if synthetic rubber becomes commercially profitable. In 1926 nitrate producers of Chile petitioned for a lower export tax to meet competition from air-fixed nitrates, and the Japanese camphor monopoly twice cut its prices because of synthetic camphor made in France and Germany. Rayon, made from wood or vegetablefiber, has stimulated the demand for the natural textiles, in some lines, because it is used in conjunction with them; but in others, it threatens to replace not only wool and cotton, but silk as well. Without artificial leather the automobile industry would have been tremendously handicapped in providing tops and seat covers, and the discovery of synthetic lacquer and varnish has meant tremendous savings in both time and money. Any program designed to stabilize either industry or prices must take into consideration both chemical discoveries and inventions, for they not only benefit the consumer by lowering prices, but also threaten the existence of established industries. It has not been possible to secure an article dealing with inventions, but the following paper by Dr. Weidlein provides a comprehensive picture of the changes that have taken place in industry as a result of chemical discoveries.-EDIToR.