120 Boweries Arialyns of Calcareous Tinigsten^ ^c. 



talc which was produced when collected and dried at a 

 low red heat weighed 34,75 grains. It was rcdissolved hi 

 muriatic acid with effervescence, excepting .46 of silex, and 

 again precipitated by sulphuric acid ; it was therefore car- 

 bonate of lime. Deducting the .46 grain of silcx, it amount- 

 ed to 34.29 grains of carbonate, which equal 19.36 lime. 



E. The alkaline sohition containing the tungstic acid 

 was evaporated to dryness, when it appeared in the form 

 of small crytalline grains. The mass b^ing treated with 

 Water there remained undissolved a brown powder, which 

 when dried, weighed 1.75 grain. Nitric acid dissolved 

 the metallic oxides by which it was coloured, and left 1.13 

 grains of silex. The nitric solution was precipitated by 

 ammonia, and the precipitate afterwards treated with mu- 

 riate of ammonia as before, (C) when it was found to con- 

 sist of oxide of iron .48 grain, and oxide of manganese .12. 

 The results (in C and E) give a total of oxide of iron amount- 

 ing to 1.03 grains and 5f oxide of manganese equal to .31 



grain. 



F. The solution (E) was then decomposed by muriatic 



acid, and the precipitate whicli was produced collected and 

 dried at a red heat; it assumed a yellow colour; and weigh- 

 ed 76.25 grains. Liquid ammonia when digested upon it 

 dissolved it almost entirely, leaving .20 grain of silex. 

 The ammoniacal solution Avhqn evaporated yielded white 

 needle form crystals, which became of a yellow colour 

 when calcined. They were completely redissolved in am- 

 monia, and again precipitated by acids. This powder was 

 therefore the tungstic acid. Deducting the 20 grains of 

 silex, it amounted to 76.05 grains. The results (in B. C. 

 D. E. and F.) give a total of silex amounting to 2.54 



g 



rains. 



One hundred grains of the calcareous oxide of Tungsten 

 consist, according to this analysis of 



Tungstic acid, - - - 76.05 



Lime, 

 Silex, 



19.36 



2.54 



Oxide of Iron, - • - . 1,03 



Oxide of Manganese, - - - 0.31 



99.29 



1 00.00 



000.79 Loss. 



