St^S Curjoty Viev) of fame of the 



Vauquelln has analyfed the green feld-fpar, caUad by fome 

 the amazon ftone. It gave : 



Silex - - . 62*83 

 Alumine - - - 17*00 

 Lime _ _ _ 03*00 

 Oxydofiron - - ci*oo 

 Potaih - - - 1 5* 00 

 Lofs _ _ . 03*13 

 Here then we have potafh extra6led from the lepidollte 

 and feld-fpar, fubftanccs of the primary ftrata. 



Dr. Kennedy has extra6led potafh from pumice ftond. 

 The analyfis he gives of it is as follows : 

 Silex, 

 Alumine, 

 Oxyd of iron, 

 Potafli, 

 The lava of .-Etna and bafaltes gave him ^oda or natron. 

 We have therefore feven mineral fubftances from which 

 fixed alkalies have been extradHed, viz, 



I ft. The alumiaite of Tolfa, according to Monnet and 

 Bergmann, contains potafh. 



;2d, The liliceous depofits of Geyer contain foda, according 

 to Black. 



3d, The leuclte, according to Klaproth, contains potafli. 

 4th, The lepidolite, according to Vaucjuelin and Klap- 

 roth, contains potafh. 



5th, Green feld-fpar, according to Vaxiquclin, contain* 

 potafli. 

 , 6th, Pumice flone contains potafli, according to Kennedy. 

 7th, Lava and bafaltes contain foda, according to Ken- 

 nedy *. 



It has been propofed, therefore, to make of the flones 

 which contain alkalies, a genus under the name of the alka- 

 liferous. 



'■'■' When we confider how abundant iniiriat of foda is in nature, a fub- 

 flance which, with the aid of heat, forms a good llux for many fubftances, 

 we need not be furprifed at finding foda in any volcanic produdion.— 

 Edit. 



Napione 



