Tntelliycnce and MisceUaneuns Articles. 585 



ployment of heat. Nitromuriatic acid quickly converts it into red . 

 oxide, of which a small portion dissolves. Treated with sulphuric 

 acid, it is quickly converted into the sulphate. This salt was found 

 to consist of — 



Sulphuric acid 31*236 



Oxide of donarium 47*734' 



Water 21*030 



Admitting that the oxygen of the sulphuric acid amounts to three 

 times that in the oxide, we should find 6*24' parts in it, which, sup- 

 posing the oxide to be R^O^ would give for the metal the atomic 

 weight 997*4, and for the oxide 2294*8 ; or 100 parts of oxide con- 

 tain 13*072 oxygen. 



The oxide of donarium obtained by strongly calcining the hydrate 

 is of a very dark red colour, and forms a heavy powder. In a very 

 fine state of division, it has an orange colour, becomes darker when 

 strongly ignited, but again paler on cooling. According to one 

 determination, its specific gravity is 5*576. The strongly- calcined 

 oxide is not attacked by hydrochloric, nitric, nitromuriatic, nor even 

 by hydrofluoric acids. Nothing is reduced or dissolved on long 

 digestion with hydrochloric acid to which a little alcohol, sugar, 

 tartaric or oxalic acid has been added. Only by the long-continued 

 action of concentrated sulphuric acid is the mass rendered soluble 

 when subsequently diluted with much water. Strongly-calcined 

 zirconia dissolves far more quickly in strong sulphuric acid than the 

 oxide of donarium. When, on the contrary, the oxide has only been 

 exposed to a temperature sufficient to expel the water from the hy- 

 drate, it is j^lightly attacked by hydrochloric acid without any dis- 

 engagement of chlorine. 



The solutions of the hydrated oxide in nitric and sulphuric acid 

 are colourless ; that in hot hydrochloric acid is yellow, almost like 

 a solution of iron. The colour of this solution disappears almost 

 entirely on cooling, but is again reproduced by warming. 



Tiie oxide is precipitated from its solution by potash and soda, and 

 is not soluble in an excess of the precipitant ; ammonia behaves in 

 a similar manner, but the precipitate is m6re bulky, resembling alu- 

 mina precipitated by ammonia. The carbonates of potash, soda and 

 ammonia, as well as the bicarbonates, produce a white precipitate, 

 which dissolves very readily in an excess of the precipitant. Oxalic 

 acid immediately produces a thick white precipitate in a neutral or 

 acid solution, which is insoluble in free oxalic acid, but can be dis- 

 solved by a large addition of hydrochloric acid and the application 

 of heat. A concentrated solution of sulphate of potash j)io(luces a 

 precipitate very slowly in the sulphuric solution, which dissolves on 

 the addition of water. Terrocyanide of potar^sium furnishes a flesh- 

 coloured precipitate, inclining to brown, in a neutral solution. Car- 

 bonate of baryta comi)l(ti.ly separates oxide of donarium from its 

 solutions; sulpliuret of ammonium gives a daik green Hocculent 

 preci|)itate, insoluble in an excess. Ferrideyaniile of potassium, 



Phil. May. S. 1. No. 7. ^uppl. Vol. 1. ^ K 



