STABILITY TESTING OF :i.•... '¾organisms to appear just won't .'i?!i' do, and the only way to reach a quick !•}i!i •:" and decisive answer is to use bacterio- [!i'•' logical methods of evaluation. This ?. is, done by inoculating' the shampoo }?::::'•ith moulds, bacteria and sewage ??:organisms which have been found to ?!i•i!': contaminate shampoos, and examin- !}!:i?ing the shampoo for colony growth •}?or gas formation. !•(i!" The packaging of shampoos does ( i::}not pose any serious stability pro- {::':::i: blems, with the exception of cream ii}i(' shampoos in collapsible tubes. The ::i! i:':quickest .way to determine whether :½i: :..: or not the product will corrode the ':?Container is to oven-test it for 30 ?30 days at 130 ø F. :..) i TESTING HAIR FIXATIVES :}':•? Preparations to hold the hair in i{:(:::: place, especially some of the newer .!i::,, : types, have grown in popularity and ' i:? include,. in addition to the brillian- :4 : ?:i tines, oil emulsions and pomades-- ?.:a variety of hair setting preparations .. {:i•i: based upon gums, resins and pro- ?:.}.] teins. The aqueous preparations are ?:?: generally clear, dilute solutions of }i :/ gums or proteins and may be thin fluid preparations or viscous, stringy ß ': : solutions such as those based on gum karaya. Accelerated tests are usef• here, especially those which might induce precipitation or turbidity. ': These products readily support the growth of micro-organisms if not adequately preserved. Concentrated wave set prepara- tions are' manufactured for beauty shop use and consist essentially of an alcoholic suspension of a water- soluble •m, plus other additives. HAIR PREPARATIONS This concentrate is added to water to make a product ready for use. The problem or difficulty that must be looked for here is the caking of the suspended gum so that the con- centrate cannot be poui-ed out of the bottle. Two useful stability tests are prolonged vibration and oven- testing at 90 ø F. Non-aqueous hair sets are formu- lated to be sprayed on the hair and are either packaged in a polythene squeeze bottle or as a low-pressure aerosol. These products must remain clear without the formation 'of any sediment, precipitate or crystals which may clog the spray head or valve. The aerosol preparations are best oven-tested at 130 ø F. for a period of 30 days, the can being then examined for corrosion. These hair set preparations shoul•l always be checked for functional stability by using the product on live models. The film deposited on the hair must dry quickly, must not flake off, must not be sticky or rough. A simple routine test is to spray the liquid on a flexible sheet of clear plastic and examine the film for tackiness, flexibility, clarity, etc. Successful cosmetics are the result of' (1) (2) (3) (4) (5) Rigid control of raw materials. Careful formulation. Meticulous care in manufac- ture. Maintenance of close toler- ances in the finished product. An exhaushve testing pro- gramme, both in the labora- tory and in the field. 187

NON-FLORAL PERFUMES By E. S. MAURER, F.C.S., M.R.I.* THIS IS not an original :theme. Many writers have touched on it before. x As far back as January 1939 an anonymous article appeared under the same title, • the follovdng intro- ductory paragraph from which epito- mises the subject:"It is often asserted that, in spite of the enormous num- ber of synthetic chemicals now used in perfumery, the art has its basis in flowers and their fragrance. Historically, however, it may be questioned whether .this assertion is correct. The ancients made their perfumed oils mainly with the aid of spices and aromatic woods and resins and, although the popularity of floral perfumes is impressive, there is, nevertheless, a big and increasing production of perfumes in which the predominant note is not a floral one." It is interesting, however, to observe that the above-mentioned article is sub-titled, "a catalogue of a few materials with which the perfumer can reconstruct the odours of leathers, precious woods, balsams, spices, etc.", and most of the items quoted are proprietaries of well- known English and Continental firms, many of which have earned the esteem of perfumers during the * Chief Chemist, Messrs. A. G. Hersom, IKingston-upon-I hames, Surrey. 188 past decade. The author rightly emphasises the difficulty of attempt- ing to classify odours of a non- floral type and proceeds to give a brief dissertation upon some of the groupings as outlined by ½erbelaud in his Formulaire de Parfumerie. 3 Those who are familiar with this classification of odours Of the same and neighbouring tonality will per- haps recollect that the osmical panorama extends to no less than 45 groups but, broadly speaking, it is seen that this scheme lends itself to a division showing the "pure floral" or blbssom elements as one third ß the second portion of similar. magnitude being devoted to the "pharmaceutical" essential oils ofl ß perfumery usage while the remain- ing third embraces transitional :.[ groups and the folial, animal, fruity:! and other ancillaries. These auxiliaries, as is well known,'?! have become of increasing import-:i! I ance in modern perfumery composi•:?} tion and in almost every case they.li represeni a "quality" rather than specific odour and may perhaps termed the perfumery "adjectives,i'..11!i•i i or more succinctly expressed "adjuvants." The dictionary affords a particU2::ii!i larly apt deftnition of an adjuvan?•