BOOK REVIEWS 43 betical index giving the code number under which every term appears. These indices materially enhance the value of the Lexicon to the non- English-speaking user. Whilst it is difficult to check the accuracy of the cited equivalents in many of the tongues, it is in the relevance and adequacy of the words and phrases selected that the Lexicon demonstrates its worth. All are terms recognized in United Kingdom practice whilst some purists might object to such American infelicities as "go-no-go gauge" and "unscrambler," these phrases are nevertheless widely used. In passing it is noted that the compiler acknowledges, as indeed does Webster (3), both spellings of propell(a/e)nt. As is well known the "a" version, traditionally employed for solid fuel propulsion, has been widely adopted by the aerosol filling industry and followed by a number of the specialist journals, whilst the alternative spelling is recommended by the British Standards Institution and has been used for many years by the largest producers of halocarbon propellents (sic) both in the United Kingdom and the U.S.A. Today, authorities in many countries are showing interest in regulations regarding safety in production, distribution and use of pressurized (aerosol) dispensers (4-6), whilst national and international agencies variously con- sider standard specifications and procedures. Accurate and unambiguous translation of specialised terms at international meetings and working groups is therefore particularly important this Lexicon has already proved useful for that purpose. It might be even more helpful if the compiler could be persuaded to include the equivalent abbreviations for some of these terms when a revised edition appears. It is concluded that this Lexicon is a timely and valuable contri- bution to the consolidation and further expansion of a vigorous industry. G. F. PHILLIPS. REFERENCES (1) YIerzka, A. and Pickthall, J., Pressurised Pachaging (.4erosols). 2nd edn. (1961) Butter- worth & Co: London. (2) Glossary of Technical Terms The Metal Box Company: London. (3) Webster's New Internationa• Dictionary, 2nd edn. (1961) G. Bell & Sons Ltd.: London. (4) Phillips, G. F. J. $o•. Cosmetic Chemists 14 357 (1963). (5) $•e½ialities 1 34 (December 1964). (6) Schuddeboom, L. J..Mfg. Chemist zlerosol News 3• 82 (July 1964).

Society of Cosmetic Chemists of Great Britain DIPLOMA EXAMINATION Brunel College PAPER I (Wednesday, 24th June 1964.) Candidates should answer FIVE questions only one question from each section. Each answer must be commenced on a separate sheet of paper or book. Where possible, express relationships and reactions in equations with a full explanation of symbols used, and give simple sketches where appropriate. SECTION A 1. With particular emphasis on the nature and importance of side chains, describe the way in which the polypeptide chains of hair keratin can be built up from simple compounds. To what extent and under what conditions are the cross linkages modified during a permanent waving process ? 2. A coloured substance is of value in hair colourants only if it can be attached to the hair. Discuss the various methods which can be used to ensure satisfactory uptake with reference to (a) the chemical constitution of the dye molecule and (b) the environment of the dye molecules. To what extent can the present dye products be considered as ideal hair colourants. .3. Discuss with specific examples the formulation of the following hair- dressing products :-- (i) Liquid brilliantines. 4S