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INFRARED APPLICATIONS TO THE ANALYSIS OF COSMETICS AND ESSENTIAL OILS* By H^•.R¾ H. H.•USDO•.•'•' The Perkin-E/ruer Corporation, Norwa/k• Conn. IN SPITE of the fact that most industries and research laboratories have already made wide use of infrared spectroscopy as an analytical tool for more than a decade, it seems that the cosmetic and perfume industries have only recognized the potentialities of this method during the past two years. To some extent this neglect of infrared potentialities derives from the inherent nature of the industry, since ultimate product specifications must often be based on a psychological reaction of odor or color. Infrared cannot be considered as a replacement for such specifications but it can be an invaluable supplementary tool in determining purity of raw materials, * Presented at the May 15, 1953, Meeting, New York City.