LONDON. Physical Society, November 12.—Mr. G. Johnstone Stoney, Vice-President, in the chair.—Mr. J. Rose-Innes read a paper on the isothermals of ether. The well-known generalisations of Boyle and Gay-Lussac with regard to the pressure, volume, and temperature relations of gases, were examined by Ramsay and Young, who deduced the law p = bt - a, i.e. that pressure is a linear function of temperature, at constant volume, where b and a are functions of volume only.