Note 89 — Chapter XI · TO HEKLA AND THE GEYSIR IN HAUKADALR.[87]
Reading edition
Professor Tyndall (loc. cit.) tells us that the “two first gases cannot exist amicably together. In Iceland they wage incessant war, mutually decompose each other, and scatter their sulphur over the steaming fields. In this way the true solfataras of the island are formed.” He derives the vapour of sulphur in nature from the action of heat upon certain sulphur compounds.