of phosphate rock useful and serviceable to man in the enrichment of the soil; he has taught how to make waste products of other industries useful and available for fertilization and he has shown how to make the gas works contribute to the fertility of the soil. In the soda industry, the chemist can successfully claim that he has founded it, developed it and brought it to its present state of perfection and utility, but not without the help of other technical men; the fundamental ideas were and are chemical. In the leather industry, the chemist has given us all of the modern methods of mineral tanning, and without them the modern leather industry is unthinkable. In the case of vegetable-tanned leather he has also stepped in, standardized the quality of incoming material and of outgoing product. In the flour industry the chemist has learned and taught how to select the proper grain for specific purposes, to standardize the product, and how to make flour available for certain specific culinary and food purposes. In the brewing industry, the chemist has standardized the methods of determining the quality of incoming material and of outgoing products, and has assisted in the development of a product of a quality far beyond that obtaining prior to his entry into that industry. In the preservation of foods, the chemist made the fundamental discoveries; up to twenty years ago, however, he took little or no part in the commercial operations, but now is almost indispensable to commercial success. In the water supply of cities, the chemist has put certainty in the place of uncertainty; he has learned and has shown how, by chemical methods of treatment and control, raw water of varying quality can be made to yield potable water of substantially uniform composition and quality. The celluloid industry and the nitro-cellulose industry owe their very existence and much of their development to the chemist. In the glass industry the chemist has learned and taught how to prepare glasses suitable for the widest ranges of uses and to control the quality and quantity of the output. In the pulp and paper industry, the chemist made the fundamental observations, inventions and operations and to-day he is in control of all the operations of the plant itself; to the chemist also is due the cheap production of many of the materials entering into this industry, as well as the increased and expanding market for the product itself.