ON VEGETABLE ACIDS 



270 



Three varieties of zeolite have been discovered in the 

 mountains of the Hart/ and the Tourmalin, or Mount 

 Gothard in Switzerland. 



In Cornwall, two mines have been found extremely rich 

 in the new mineral or acid, tungsten, which the experiment 

 of Bergmann and Scheele have rendered so famous. 



Prussian blue is half composed of iron, although Berg- 

 mann has maintained the contrary. 



Mr. Scheele has just discovered that the salt obtained 

 from urine, and known under the name of acidum perlatum, 

 is not a peculiar acid ; but that it is only phosphoric acid, 

 disguised by a small quantity of fossil alkali that is united 

 with it. The analysis is confirmed by synthesis ; for by 

 combining fossil alkali with phosphoric acid the author has 

 obtained a true perlate acid. Journal de Physique, p. 316, 

 October, 1785. 



