During studies of electrolysis of beryllium salts in non-aqueous solvents, Booth and Torrey (1) discovered that cold beryllium acetylacetonate rapidly absorbed sulfur dioxide to form a liquid. The sulfur dioxide could be boiled off by gentle warming and recondensed, dissolving the beryllium compound as frequently as desired without any apparent change in the beryllium acetylacetonate. A sample of the sulfur dioxide-beryllium acetylacetonate solution containing some crystals was sealed off in a test tube and has remained unchanged for the last eight years.The remarkable absorbing power of this beryllium compound immediately suggested to the discoverers that, in the first place, the study of this reaction might yield information of interest, since it apparently represented a novel type of reaction, possibly a general one, with metallic compounds containing a C:0 grouping. The second point is of course the possible application of this reaction to the development of an absorption type refrigerator.HISTORICAL DISCUSSION If, as Booth and Torrey thought, the reaction of sulfur dioxide on beryl-SUMMARY 1. The systems sulfur dioxide-beryllium acetylacetonate and sulfur dioxide-beryllium ethyl acetoacetate have been studied at 25°C. It is found that these beryllium compounds combine in the ratio of one mole of compound to one mole of sulfur dioxide.2. The vapor pressure of the compound BeCCHaCOCHCOCHa^• S02 averages 73 cm. and that of the compound Be(CH3COCHCO-OC2HB)2 • S02 averages 60 cm.3. The nature of these compounds and their possible structure is discussed.4. The baro-buret is found to be a valuable tool in studying gas-solid equilibria.