Second- Appendix, § II. Zeolytes. The zeolytes generally contain from 4 to 4 of their weight of water, an ample teftimony one would think of their Neptunian origin. Yet the circumftance of their being found in the vicinity of iome volcanos has induced many to imagine fuch a conneftion between them and volcanic operations, that from their exiftence, at leaft in certain circumflances, they have thought them- felv.es intitled to conclude, that the rocks in which they are fonnd were fubjeded in fome antient period to fuch operations. Some have afcribed their origin to the decompofition of lavas; fome to the infilrration of fea-water through lavas; and fome imagined them inveloped ln lavas in adual fufion. The foliowing fads, ho weyer, fubvert all thefe opinions: ift, Zeolytes are found in countries vvhere no thing is volcanic, unlefs the whole earth be deemed fo. They are found in copper and gold mines in Sweden. 3 Bergm. 224. They are found between granites in malfes of fome hun- dreds weight in Poland. 2 Chym. Ann. 17911 196. They are found amidft the granites of St. Gothard in Swilferland. Haiding. 52. 2d, Zeolyte is not found in the lavas either of /Etna or Vefuvius, and, indeed, fcarce at all on thofe