800 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS 5.3 Identification of bacteria Breed, R. S., Murray, E. G. D. and Smith, N. R. Bergey's manual of determinative bacteriology 7th Edn. (1957) (Williams & Wilkins, Baltimore). Cowan, S. T. and Steel, K. J. Identification of medical bacteria (1965) (Cambridge University Press, London). Gibbs, B. M. and Skinner, F. A. Identification methods for microbiologists (Part A, 1966 and Part B, 1968) (Academic Press, London). Taylor, J. The isolation and identification of satmonellae (Broadsheet 58) (October) (1967) (Association of Clinical Pathologists, London). Trevor Willis, A. Anaerobic bacteriology in clinical medicine 2rid Edn. (1964) (Butterworths, London). Simpton, D. A. and Gould, G. W. Isolation methods for microbiologists (Technical Series 3, 1969) (Academic Press, London). 5.4 Identification of yeasts and moulds Lodder, J. and Kreger-Van Ri], N.J. W. The yeasts--a ta vonomic study (1970) (North Holland Publishing Co. Amsterdam). Smith, G. An introduction to industrial mycology 6th Edn. (1969) (Edward Arnold Ltd., London). 6. SI UNITS AND CONVERSION FACTORS SI UNITS physical quantity name of unit length metre mass kilogramme time second hour force newton power watt customary temperature, t degree Celcius symbol for unit m kg s h N W øC definition o! unit kgms -2 = J m-• kgm2s -3 • J s -• t/øC = T/øK ---273.15 Symbols for units do not take a plural form. /'taction prefix 10 -2 centi 10- 3 milli 10- 6 micro 10- 0 nano FRACTIONS AND MULTIPLES symbol multiple c m 103 n prej•x kilo symbol k UNITS CONTRARY TO SI, WITH THEIR EQUIVALENTS physical quantity unit equivalent length angstr6m 10 -•ø m pressure pound (f)/sq.in. 6.894 76 kN m -2 temperature degree Fahrenheit t/øF=•T/øC+ 32 (Received: 7lst July 19•0)