Letter from W [William] Ramsay, Tullochgorum, Boat of Garten, Inverness-shire, to [Joseph] Larmor Pure argon and pure krypton were used in the electroscope, and Ramsay describes other gas mixtures, including xenon diluted with oxygen because of its scarcity. The rate of discharge was proportional to the density and pressure. This opens up questions such as 'do you imagine that the atoms actually get bittocks knocked off them?' He discusses elements having the same spectra before and after 'maltreatment' such as radium giving off helium. He is not of a speculative nature, but he is curious to know how the helium is evolved. He saw Foster regarding publication, and he thought it better that the radiation papers should appear together. 4 August 1903