Radio-active Gas from Bath Mineral Waters

Abstract

PROF. J. J. THOMSON has shown that the air extracted from Cambridge tap-water and from the waters of certain deep-level springs is mixed with a radio-active gas (NATURE, vol. lxviii. p. 90). It appeared of special interest to determine whether such a constituent existed in the hot mineral springs of Bath. Samples of water direct from the King's Bath Spring have been examined at the Blythswood Laboratory, and have been shown to contain a radio-active gas in solution. In the first experiments the gas was expelled from a flask containing a litre and a half of water by boiling under a pressure of about half an atmosphere. The amount of gas obtained after passing through a number of drying tubes was small, as was shown by the fact that the pressure only altered by a few centimetres. Yet this was sufficient to produce a marked increase in the ionisation in the testing vessel. The gas was also extracted from the water by exhausting the testing vessel and allowing a current of air to bubble through the water and a series of drying tubes into the vessel. In this case the ionisation current increased from four to five times.