On the 7th of January 1839, I communicated to the Royal Society of Edinburgh a pretty detailed account of the singular mineral and gas springs of Kissingen, in Bavaria, then much less known than at present to English travellers. I refer to this paper, printed in the Edinburgh New Philosophical Journal, April 1839, for the details of the most curious of these, a saline spring called Kunde-Brunnen, which was at that time regularly periodic; a copious and turbulent discharge of brine, mixed with torrents of carbonic acid gas, recurring six or eight times in the twenty-four hours. This phenomenon, exactly as described in my paper, appears to have continued with slight variation ever since, that is, for a period of twelve years, subject, however, to the variation formerly mentioned, that when the brine is actively withdrawn by pumps, for the manufacture of salt, the periods lengthen.