THE SEVENTH SPECIAL AWARD 347 water emulsion to that of the water-in-oil emulsion. The HLB value of an emulsifier was shown to be calculable from the chemical formula by sum- ming up the group numbers for the various hydrophilic and hydrophobic groups in the molecule to obtain a net value. Additional studies on interfacial viscosities of monolayers at the oil- water interface were reported in 1959 (13). These studies confirmed earlier suggestions that high interfacial viscosity is correlated with high emulsion stability. Emulsification and general cosmetic problems were examined as early as 1952 (3) (from a thermodynamic and kinetic viewpoint), and the phe- nora enon of spontaneous emulsification was further investigated in 1957 (12). In the field of olfaction (5), Davies suggested in 1953 that a limiting factor in the production of olfactory sensation by any odorant was the ability of the odorant to penetrate and puncture the bimolecular lipid layer of the olfactory cell membrane. With Taylor (6, 7), he reported in 1954 on measurements of the effectiveness of various odorants in ac- celerating the hemolysis of red blood cells by saponin. The red cell was a convenient substitute for the olfactory cell and was believed to possess a membrane of similar type, wherefore penetrating power should be similar in the two cases. The logarithms of accelerating potencies of the odorants on red cell hemolysis were shown to be inversely proportional to the log- arithms of their olfactory thresholds. In other words, the odorants de- tectable in the highest dilution also exerted the greatest effect upon penetra- tion of the cell membrane. In 1957 Davies (9) reported a correlation between olfactory thresholds and free energy of adsorption at the oil-water interface. Molecular size and shape of odorants were held to be factors in influencing the dislocation produced in the olfactory membrane. An equation also was derived for predicting olfactory thresholds from hemolytic accelarating power and molecular volume and shape. Much of the work quoted above is included in the book Interfacial Phenomena, by J. T. Davies and E. K. Rideal, Academic Press (1961). SELECTED BIBLIOGRAPHY REFERENCES (1) Davies, J. T., "Distribution of Ions Under a Charged Monolayer--Surface Equation of State for Charged a Film," Proc. Roy. Soc., 208A, 224 (1951). (2) Davies, J. T., "Measurement of Contact Potentials at Oil-Water Interface," Nature, 167, 193 (1951). (3) Davies, J. T., "Surface Chemistry and Its Application to Emulsion and Cosmetic Prob- lems," Perfumery Essent. Oil Record, 43, 338 (1952). (4) Davies, J. T., "Application of Gibbs Equation to Charged Monolayers and Their Desorp- tion from the Oil-Water Interface," Trans. Faraday Soc., 48, 1052 (1952). (5) Davies, J. T., "Odor and Morphology of Molecules," Ind. de la Perfumerie, 8, 74 (1953). (6) Davies, J. T., "Odor and Morphology of Molecules," Ind. de la Perfumerie, 8, 74 (1953). Nature, 174, 693 (1954).

348 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS (7) Davies, J. T., and Taylor, F. H., "Olfactory Thresholds: A Test of a New Theory," Perfumery Essent. Oil Record, 46, 15 (1955). (8) Davies, J. T., "A Surface Equation of State for Charged Monolayers," •7. Colloid Sci., 11, 377 (1956). (9) Davies, J. T., and Taylor, F. H., "Molecular Shape, Size and Adsorption in Oilaction," 2nd Int. Cong. of Surface Activity (London), BU 358 (1957). (10) Davies, J. T., "A Study of Foam Stabilizers, Using a New (Viscous-Traction) Surface Viscometer," 2nd Int. Cong. of Surface Activity (London), BZ 240 (1957). (11) Davies, J. T., "A Quantitative Kinetic Theory of Emulsion Type, I. Physical Chemistry of the Emulsifying Agent," 2nd Int. Cong. of Surface Activity (London), CT 409 (1957). (12) Davies, J. T., and Haydon, D. A., "Spontaneous Emulsification," 2nd Int. Cong. o Surface Activity (London), EK 400 (1957). (13) Davies, J. T., and Mayers, G. R. A., "Studies on Interfacial Viscosities of Monolayers," Trans. Faraday Soc., 56, 691 (1960). ADDITIONAL BIB LIOGR.APHY Davies, J. T., and Rideal, E. K., "Kinetic Salt Effect on Monolayer Reactions," Proc. Roy. Soc., 194A, 417 (1948). Davies, J. T., and R•deal, E. K., "Distribution of Ions at the Interface: Concept of a Solid Phase," •7. Colloid Sci., 3, 331 (1948). Davies, J. T., "Monolayers of Some Diesters," Trans. Faraday Soc., 44, 909 (1948). Davies, J. T., "Preparation of Monolayers of Monocetyl Succinate," "Research" Supplement Surface Chem., 1949, p. 95. Davies, J. T., "Lactonization of'•-Hydroxystearic Acid in a Monolayer," Trans. Faraday Soc., 45, 448 (1949). Davies, J. T., "Diffusion of Ions Across a Phase Boundary. and Three Cell Walls," y. Phys. & Colloid Chem., 54, 185 (1950). Danielli, J. F., and Davies, J. T., "Reactions at Interfaces in Relation to Biological Problems," /idvances in Enzymes, 11, 35 (1951). Davies, J. T., "Shape of Molecules of Polyamino Acids and Proteins at Interfaces," Biochem. andBiophys./icta, 11, 165 (1953). Davies, J. T., "Interfacial Potential I: Dependence on the Character of the Nonaqueous Phase," Trans. Faraday Soc., 49, 683 (1953). Llopis, J., and Davies, J. T., "Catalysis of Surface Reactions Due to Electrical Charges," /inales real soc. Espag.fis. y quire. (Madrid), 4913, 671 (1953). Davies, J. T., "Interfacial Potential II: Molecular Orientation of Substituted Fatty Acids and Polyamino Acids," Trans. Faraday Soc., 49, 949 (1953). Davies, J. T., and Rideal, E. K., "Penetration of Ions into Charged Films," y. Colloid Sci., 1954, Suppl. I. Davies, J. T., "Factors Influencing the Orientation ofco-Amino Groups in Monolayers of Pro- teins and Amino Acid Polymers," Blochem. •., 56, 509 (1954). Davies, J. T., "Catalysis and Reaction Kinetics at Liquid Interfaces," Advances in Catalysis, New York, Academic Press, 6, 1 (1954). Davies, J. T., and Llopis, J., "Surface Studies of a New Polyamino Acid," Proc. Rec. Sec., A227, 532 (1955). Davies, J. T., and Rideal, E. K., "Interfacial Potentials," Can. 7. Chem. 33, 94 (1955). Davies, J. T., Haydon, D. A., and Rideal, E. K., "Surface Behavior orE. Coli," I: Nature of Surface," Proc. Roy. Soc., 145B, 375 (1956). Davies, J. T., "Adsorption of Long Chain Ions" (1958). Davies, J. T., and Smith, J. A. C., "Rate of Adsorption at Oil-Water Interfaces" (1959). Davies, J. T., "Rate of Adsorption at Oil-Water Interfaces" (1959). Davies, J. T., "Monolayers of Long Chain Ions" (1959).