AEROSOL PROPELLANTS 415 me are exact. I consider temperature to be decisive for decomposition, which must be observed only above 500øC. TaE LECTURER: I would like to assure Dr. Kiibler that the actual measurement of the decomposition products leaving the convector heaters was carried out very precisely and was not "estimated". Phosgene, for example, was measured by individually calibrated Dr•tger tubes and by absorption in aqueous aniline to form diphenyl urea. I have used the word estimated only in so far as I have interpreted these results in terms of an atmosphere in a sealed room, i.e. attempted to relate the scientific tests to extreme conditions under which an aerosol might be discharged. Tempe- rature is indeed an important factor but other effects such as humidity and metal surfaces are also important so far as decomposition is concerned. }V[R. J. C. THORNTON: With regard to the thermal decomposition of halocarbons detailed in Table $ of your paper, were the temperatures of the elements in the three different convector heaters measured? T•E LECTURER: NO. The experiments were carried out with standard domestic appliances to give realistic conditions rather than to obtain additional academic information. 1VtR. H. F. FROST: Have you examined the decomposition of pro- pellants drawn through a lighted cigarette in the "domestic" experiments? T•E LECTUre R: No. We have, however, carried out work on the problem of smoking cigarettes in atmospheres containing the vapour of chlorinated hydrocarbons and the results were published by Little [Brit. J. Ind. Med. 12 304 (1955)]. In no case was phosgene found in the vicinity of the glowing tip of a cigarette smoked in the contaminated atmospheres, and even when a trace of phosgene was added to the atmosphere, it was destroyed by passage through the cigarette being smoked.

416 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS SOCIETY OF COSMETIC CHEMISTS OF GREAT BRITAIN Symposium on Aerosols A SYMPOSIUM on Aerosols organized by the Society, took place at Southport on 24th and 25th April 1963. It was attended by over 150 participants from France, Western Germany, Sweden, the Netherlands, Australia and the United Kingdom. Delegates were welcomed by His Worship the Mayor of Southport, Alderman Dr. S. J. Hepworth, J.P. The President of the Society, Mr. G. A. C. Pitt, afterwards thanked the Mayor for his kind remarks and then formally opened the Symposium. The Symposium was followed on the afternoon of the 25th April by a lively Brains Trust. A variety of questions was put to the panel consisting of Messrs. M. N. Conville, P. Dyson, J. A. T. Fisher, R. A. Gunn-Smith, and J. Pickthall. Mr. A. Herzka was the Question Master. A Civic Reception was given by the Mayor and Corporation of Southport on the evening of the 24th April at the Palace Hotel. 1963]64 Programme Lectures Venue.' The Royal Society of Arts, John Adam Street, London, W.C.2. Time: 7.30 p.m. Tuesday, 22nd October 1963. Friday, 6th December 1963. Thursday, 23rd January 1964. Thursday, 27th February 1964. Monday, 23rd March 1964. Thursday, 7th May 1964. Symposium on Hair A SYMPOSIUM on Hair will take place in Brighton, Sussex, from the 14th--- 16th April 1964. Anyone wishing to present a paper is requested to contact the Hon. Organiser, Mr. R. E. Eckton, c/o Givaudan & Co. Ltd., Whyteleafe, Surrey. Annual Dinner and Dance THIS WILL take place on Friday, 31st January 1964, at the Connaught Rooms, Great Queen Street, London, W.C.2.