There are few results available in the literature for the solubilities of gases in water over 1OOOC, and for the geologically important gas, carbon dioxide, there is no information. In this paper the presentation and interpretation of high-temperature gas solubilities is discussed, and values are reported for the solubility of carbon dioxide in water up to 3500C. The anomalous behavior of water compared with other liquids as a solvent for gases is reviewed briefly, Extrapolation of solubility data from low temperatures can be completely misleading unless it is realized that gas solubility coefficients pass through minimum values, usually in the temperature range 700 to 2000C.