RETURN FROM PITTSBURG 341 



so rich in saltpetre, or so favorable to its production, 

 that in sundry places it covers the surface in the form 

 of a rime, and that here and there in the mountains are 

 found ' mines of saltpetre/ During my stay in 

 America I had similar oral accounts, with the repeated 

 assurance that often completely developed saltpetre is 

 found in such places. 



These reports coming neither from eye-witnesses 

 nor always from sufficiently well-informed persons, 

 credence could not be blindly placed in them ; and the 

 less so, because very recently the general opinion of 

 the chymists was unfavorable either to the existence 

 or to the natural production of a pure saltpetre, al- 

 though sundry travellers have affirmed that small salt- 

 petre-crystals, produced and shaped naturally after 

 rains, have been found on the surface of the earth in 

 Pegu, Bengal, and certain regions on the coast of 

 Africa, and that in India, Spain, and elsewhere true 

 saltpetre has been got from the earth without the aid 

 of ash-lye. These accounts are now confirmed by the 

 following similar discoveries made in America. 



In Wyoming I was taken to a rock from which at 

 one time saltpetre had been gathered by scraping. A 

 loose, fine-grained, species of sand-stone, associated 

 with a considerable quantity of mica, lay piled in 

 couches of varying thickness. The color of the stone 

 was in part greyish, in part reddish, the stone itself 

 being of different degrees of hardness ; but on the 

 whole the side exposed to the air was the softest. 

 These rocks formed steep, rent walls, 25-30-40 feet 

 in height, and were the basis of a high mountain, 

 grown up in trees and bush, running along the Sus- 

 quehannah river. Many narrow, perpendicular clefts 



