iv. 300.
Die erlöschenen Vulkane in der Eifel, S. 59.
Dr. Gmelin, of Tubingen, detected the presence of ammonia both in clinkstone lava and in columnar basalt (American Journal of Science, iv. 371).]
Geology and Extinct Volcanoes of Central France, p. 60 (second edition).
Mr. William Longman has informed me that some years ago he had ice given him in summer, when he was on a visit to the inspector of mines at Pont Gibaud, and he was told that it was formed in a neighbouring cavern during the hot season.