Mineralogy. 361 



ness, left some yellow oxide of uranium. From a solution of the latter 

 in nitric acid, which was of a fine yellow, ammonia gave a yellow precipi- 

 tate, and the cyanuret of iron and potassium a fine blood-red one. 



F. That part of the brown precipitate in B, which was not soluble in car- 

 bonate of ammonia, was soluble in dilute muriatic acid, with the exception 

 of a small quantity of a dark-brown substance, which proved to be oxide 

 of manganese. The solution was neutralized with ammonia, and then a 

 crystalline coat of pure sulphate of potash introduced. A white pulveru- 

 lent precipitate began to form one hour afterwards. At the end of twen- 

 ty-four hours it was separated by filtration, washed with a saturated solu- 

 tion of sulphate of potash, and then digested in a solution of caustic po- 

 tash. A dirty white precipitate was left, which became darker on the fil- 

 ter, and proved to be oxide of cerium. On being treated with concentrat- 

 ed muriatic acid, chlorine was disengaged in a higher temperature, and a 

 trace of a white substance was left undissolved, which might be zirconia. 



G. The liquid left after the separation of the oxide of cerium, on being 

 mixed with caustic ammonia, gave a little iron, still containing some man- 

 ganese ; a trace of the latter wa§ also discovered in the liquid remaining 

 after separating the oxide of iron. 



The result of the analysis was, 



Titanic acid, - - - - 62.75 



Lime, ..... 12.85 



Protoxide of uranium, - - - 5.18 



Oxide of cerium, (impure) - - - 6.80 



Protoxide of manganese, ... 2.75 



Oxide of iron, - - - - 2.16 



Oxide of tin, ..... n.61 



Water, - 4.20 



97.30 



Besides a trace of magnesia, and much fluoric acid. 



Dr Woehler does not give any formula to represent the chemical con- 

 stitution of the species. He could not determine the quantity of fluoric 

 acid, which he believes to be very considerable, and as two per cent, of 

 fluoric acid will combine with seven per cent, of lime, the quantity of 

 it must necessarily affect the computation. There might be also some 

 zirconia in the precipitate, deposited in E from the carbonate ammonia, 

 in which, on account of the small quantity of it, only tin and cerium 

 were discovered. 



32. Native Gold in Vermont. — A fine piece of native gold, of nearly ten 

 ounces was lately picked up by a boy near a small brook in Newfort, Ver- 

 mont. It was studded with quartz crystals. It strikingly resembles the N. 

 Carolina gold. Its specific gravity is 16.5, and it is considered worth 89 

 cent, per pennyweight. — Newton's Journal of the Arts, Feb. 1827, p. 375. 



33. Dr Brewster s Treatise on Mineralogy.— This work, in which the 

 author has been engaged for many years, will be published early next win- 



