246 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS enced perfumers should not use these specialities and that they should be skilful enough to prepare their own. I consider that however experienced and skilful a perfumer is he must accept and admire the work of other perfumers and chemists, and he should be ready to use the results of their skill and imagination, for without this readiness he cannot hope to obtain results any more than if he attempted to create perfumes xvithout the use of essential oils. The preparation of these products is a very specialised operation and always requires the services of highly skilled chemists and complex plant or apparatus. The specialities which are offered as substitutes of a natural product do not give a completely satisfying result. Their influence over a compound is different, there is a lacking in the warmth and tonality given by a natural product. Nevertheless, they are of great value when correctly used and there are many occasions when they can be intro- duced with advantage into new compounds instead of using the costly natural materials. Although only passing mention has been made of the isolates, derivatives and synthetics it must be obvious that there is no intention whatsoever on my part of underestimating their uses or belittling them. They are being produced to-day in ever-growing numbers so that at times the perfumer would welcome chemists taking much longer vacations. The number of these products is now prodigious and to attempt to memorise the odours of them is a tremendous task. Not even the most skilled perfumer could pretend to be familiar with them all. At the same time there must be some endeavour to test the new products in order to determine whether a new complex has been produced or whether they can benefit from any existing preparations. It is perhaps a little disappointing that from the countless numbers of these aromatic bodies there have been very few over the past years to give an entirely new complex or perfume base, and the perfumer who is constantly searching for new ideas would welcome any aromatic which would enable him to produce an entirely new complex, particularly one that would be accepted throughout the perfumery world. It would be fair at this juncture to say that there is a general improvement in the quality of the isolates and synthetics being produced to-day as compared with pre-war, whilst it is also true to say that the quality of the natural products has not improved. The very vehicle that is carrying the perfume has a tremendous influence on the final odour appreciation. A perfume coming off alcohol has quite a different impact on the olfactory senses than the same perfume coming off a cream or powder, and this without taking into consideration the chemical differences of the vehicles. All cosmetic raw materials have an odour which has an influence on the odour of the perfumed preparation, and I do recom- mend that great care is taken when choosing ingredients for a cosmetic preparation. When a formulation has been decided on the cosmetic chemist

THE ART OF THE PERFUMER 9.47 should not at times try to effect economy by introducing slightly inferior grades of these materials. This is sometimes done and it is a very unsound practice, for often the perfumer is then requested to prepare perfumes which will cover an unpleasant basic odour. This is very false economy because the perfumer cannot deodorise he can only offer a coverage which is some- times not successful and is always costly. The slight increase in cost of purer raw materials does so often mean that a slight decrease in perfume content can be effected which will then offset the extra cost. Not only should the ingredients be carefully controlled but the odour of the finished preparation has been spoiled very often by the odour of boxes or cartons. Preparations in glass bottles do not suffer from this, but care must be exercised that the closure is satisfactory. The packaging of cosmetic preparations in polythene bottles presents quite a different problem, and care must be taken to ensure that the constituents of the perfume in the preparation will neither attack nor permeate through the polythene. So many cartons and cardboard boxes possess an odour derived either from the board or from the glue used in sealing or sometimes even from the printing ink. Perfumes, too, will permeate these packages, and this can result in unpleasant odours not caused by the deterioration of the perfumes but from outside contact. It is therefore necessary to take the package as well as the raw cosmetic ingredients into consideration if a satisfactory preparation is to be marketed. When dealing with packages, those which have an un- pleasant odour should be investigated and the troublesome materials replaced if possible. Where this is not possible, the unpleasant odour of a package can often be removed by blowing a warm current of air over the package. Where this is not practicable then a light internal spray with a perfume similar to the one being used for the contents should be carried out and the package allowed to stand for a short while. Failing all this, it might be helpful if the finished packed preparation is lightly sprayed on the outside, for which a fine aerosol spray might well be useful. We are requested to provide a perfume for a whole range of products and this is a very difficult problem indeed. Having produced a satisfactory handkerchief perfume the perfumer must then have knowledge of all other preparations of the range. If possible, he should co-operate with the cosmetic chemist on the question of ingredients, but whether this is done or not, it is always desirable to "shelf-test" the perfumed products in an inert package and also in the package into which it is intended to be packed. An acceler- ated test can be run parallel to determine if there is any rapid deterioration, but products do sometimes show deterioration after an accelerated test, and I do not feel that a test of this type is conclusive enough. It is important to endeavour to produce some of the obvious conditions which the preparation may be called upon to endure, such as varying atmospheric conditions of different countries. From experience these have been the cause of the