102 Professor Berzelius on Thorina, 



Carbonate of thorina is precipitated by carbonated alkalies, 

 with the development of free carbonic acid, and is a subsalt, 

 whose composition I have not more nearly investigated. It is 

 insoluble in water impregnated with carbonic acid. The hy- 

 drate of thorina attracts carbonic acid from the atmosphere, 

 and, after long drying in the air, dissolves in acids with effer- 

 vescence. This does not happen when it is dried in a vacuum 

 over sulphuric acid. 



Arseniate of thorina is insoluble in water and arsenic acid. 

 It is thrown down in the form of a white flocky precipitate, 

 both by neutral and by acid arseniates. 



Chromate of thorina is a beautiful bright-yellow flocky pre- 

 cipitate, which in excess of chromic acid dissolves, and forms 

 an acid salt. 



Molyhdate and tungstate of thorina are thrown down both 

 by neutral and by super-salts of these acids. They are in the 

 form of white flocky precipitates. 



Oxalate of thorina is a white, heavy precipitate, insoluble in 

 excess of acid. In other free and diluted acids, it is very 

 sparingly soluble. If it is collected on the filter, and washed 

 with water, it speedily begins to pass milky through the paper, 

 which is prevented by the addition of a little oxalic acid to the 

 water. 



Oxalate of thorina and potash is also a white powder, inso- 

 luble in excess of acid. It is distinguished from the former 

 by becoming black on burning ; and, after the carbon is burnt 

 off, it falls, when put in water, to a milk-white mass, and the 

 solution contains carbonate of potash. 



Tartrate of Thorina. — Hydrate of thorina dissolves by di- 

 gestion in tartaric acid. If so much be added that a portion 

 remains undissolved, a neutral salt is obtained, white, flocky, 

 and sparingly soluble in ammonia, which only takes up a por- 

 tion of it. The acid solution has more of a sour than astrin- 

 gent taste, and gives, after evaporation, an acid crystalline 

 salt. - It is soluble in alcohol, leaving a neutral salt ; but the 

 solution in alcohol still contains thorina, which seems to show 

 the existence of a still more acid salt. Neither the acid tar- 

 trate, nor any of the other salts of thorina to which tartaric 

 acid is added, are precipitated by caustic ammonia in excess ; 

 and there is no sure method for separating thorina from such 



