198 H.R. Watson et al. Table 1211. Coolants in compositions Approximate proportion Nature of composition of coolant, % w/w Comments Alcohol solution (0.3-0' 5) Shaving foam (0.1-0' 2) O/W emulsion creams, (0.2-0.5) lotions, balms. Solid cologne (0.3-0.7) Gives effective cooling. Compounds residing on the face can be transferred via finger to lips, giving cooling effect hours later. This is viewed as undesirable, therefore slightly volatile compounds are preferred. Note that the effective vehicle of an aftershave is often the mixture of non-volatile components, i.e. the fragrance oil and emollients. For this reason it is better to use polar emollients such as propylene glycol than non-polar emollients such as isopropyl myristate. Very effective, with cooling noticed 10-30 sec after application. Little residue left on face, hence no transfer problems. Cooling remains 5-15 min after removal. Effective. Perception may be slow, e.g. 60 sex: after application. With suitable compounds, duration is long. Very effective. Much recurrence of cooling experienced on, e.g. the forehead. Contra-indications normally relate to the different sensitivities of different body areas' Aerosol sprays: if aerosols are inhaled, the cooling effect is likely to be noticed in the throat and lungs (although in air fresheners a very small proportion of compound gives a pleasant fresh effect). Shampoos: accidental ingress of the resulting foam to the eyes gives an intense level of cooling. Talcs: the concentration of compound which is needed to provide effective cooling on most skin areas gives intense effects in the ano-genital area. Toilet Soaps: as talcs. Deodorants, antiperspirants: very effective, but the subject associates coolness in the axillae with the wetness of perspiration. CONCLUSION In this paper only a general description of the work has been possible. In the future, we hope to publish in greater detail aspects of structure/activity correlations, and certain aspects of topical effects. We recognise that the wide range of compounds which is now available offers possible new tools for study of skin penetration and neurophysiological effects we are unlikely to extend our brief inspection of these areas, and invite specialists in these fields to take the study further. ACKNOWLEDGMENTS Many have been concerned with the work, but special mention should be made of John Gascoyne, Dorothy Mitchell, Michael Russell and Roderick Thomson (all of Wilkinson Match Research Division) who carried out most of the skin test experiments.

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