JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS iris rhizomes' and finally from the woody-rooty-cachou notes of cala- mus and patchouli to the familiar rooty-sandal fragrance of vetivert oil, its alcohols and esters all of which, when supported by clove stem, cinnamon leaf a.nd origanum oils, lead to a variety of pleasant aromas veering towards thee woody note. THE WOODY ODOURS The odours of the "precious woods," particularly cedar and san- dal, are very important in modern non-floral perfumery compositions and in this category, in view of the popularity of the citrus-incense-rose and "soir" perfumes, the vetiver note may be included. Although it is perhaps the deep, sweet and peculiarly fragrant and persistent santal-type odour associ- ated with vetiveryl acetate which has brought this ester to the fore- ground in recent years, yet it is important to realise not only the age-old Indian usage of khus-khus roots, but also the fact, noted by Piesse in his 1851 "Art of Perfum- ery," that in the early days of per- fumery in England, extracts incor- porating tinctures of vetivert roots, created quite a furore. It would appear, however, that of the aliphatic esters, vetiveryl acetate is outstanding in representing the quintessence of the vetiver characteristic without the dull and sombre notes of the oil. The other esters, from the formate to the valerianate, incline to an over- 194 fruity emphasis and, moreover, show a tendency to liberate the free acids, while the only other ester of interest is the pheny]acetate, which reveals, above the fundamental note of the acetate, as may perhaps be expected, a remarkable sweet, fruity-honey fragrance. Sandalwood 0il, E.I., like all the woody oils, is of considerable impor- tance in perfumery, not only because 'of its blending and mellowing action, but also for its equally outstanding fixative properties, which are seen to a marked extent in compounds for creams, brilliantines, bath salts, talcum and face powders. Although a deliberate overdose of sandalwood oil in a compound will result in an eastern or oriental type of aroma, yet in a.lcoholic perfumes the characteristic inflection of this oil is frequently obtrusive and more 2•.' pleasing results are achieved with':" Santalo]. Here also, the acetate is the out2 standing ester and is more stable and :it less fruity than the other aliphatics, I:! but the crystalline phenylacetate, i::: like the corresponding vetiveryl::: :? ester, is almost indispensable i n?•: powder perfumes and sachets. Support from any of the synthetics•'i is somewhat limited, but decahydroLi!: [•-naphthol formate, 'assisted benzophen0ne and phenylbutyl binol, provides a starting point industrial deodorants and somi• grades of soap perfumes, particulad•11 'i:i in' conjunction with Amyris Sandalwood, W.A.). Cedarwood 0il (Juniperus and Atlas Cedar (Cedrus ...?

very closely the sandalwood pattern, and here also the acetate the crystalline phenylacetate the two most important esters, it is interesting to note that there ::::something in the odour of these which seems to parallel the ß texal tone of cyclamen alcohol •d aidehyde, and this same isoo fundamental can be observed 'unction with the characteristic note of furfural acrolein !derivatives. Further details on this ,•ct are available in a brief . by J. R. Byers, Jr. • de rose and the linalyl and esters are too familiar to ?i?need detailed treatment here but, in :•)•i!:Passing, it may be noted that the :i:•?'basic rosewood odour is approxim- ::i !iated very closely by that of iso- ::i:.iiilbutyl heptyl ether. Mention should i?ialso be made of guaiacwood (cham- :!'i. paca) oil, in which the bland, cor- •:texal-cyclamen note is evident in ::'.its characteristic tea-rose fragrance, 11'.Which is still more pronounced in '11'!•:the acetic and phenylacetic esters ?i:of the alcohol. SMOKY AND TOBACCO-LEAF ODOURS '.!i':!.,:i'The destructive distillation Of i:! birch tree wood yields a tar, fraction- ?ation of which gives the Rectified '•!i:.10il of Birch Tar of commerce. ' The .,•, ½•: odour of this oil resembles to a con- : :::'siderable degree the aroma of smouldering brush-wood, wafted !!:: from a distance. Cade oil, prepared ?.i in a similar way from various species i'.of the juniper, lacks the slightly medicated guaiacol tone of birch tar PERFUMES and is perhaps more reminiscent of peat smoke under similar conditions, especially when the oil is blended with triethanolamine pyrolignate. It is also interesting to note in passing that the hydrocarbon Cadi- nene is also present in such rooty and woody oils as camphor, cedar, galbanum, patchouli, savin, sassa- fras, santal and wormwood. Variations upon the clary sage- coumarin-bergamot theme provide useful bases for bruy•re, genista and gorse perfumes, when shaded with birch tar oil, and begin to show an approach to the cubitand or habana tobacco leaf note, while from the mor& pronounced peaty tone of cade oil, these bases--especially when used in conjunction with the cedryl and santalyl phenylacetates--result in compounds which exhibit a marked approach to the. peculiar fragrance associated with Harris Tweed. THE ODOUR OF RUSSIAN 'LEATHER Although the characteristic aroma of Cuir de Russie can be achieved by simple permutations upon the birch tar-bergamot-petitgrain specifica- tion, and that of Peau d'Espagne by the further addition of sandalwood oil, there is always a certain after- math of harsh undertones, and while variation to allow the inclusion of Castoreum eliminates this unwanted inflection to a large degree, yet even in comparatively small doses, the persistency of the animal-manure note is inclined to be obtrusive. If, however, such basic compost- 195