Chemical Science. 387 



poured out, finely pulverised, acted upon by nitric acid, and the un- 

 dissolved silica separated. The lead is then to be precipitated by 

 sulphuric acid, and the liquid evaporated to dryness, to drive off the 

 nitric acid ; the residue is to be dissolved in water, the alumina and 

 metallic oxides precipitated by ammonia, the lime and magnesia by 

 carbonate of ammonia, and the filtered liquid evaporated to dryness. 

 The residue is to be strongly heated in a porcelain (not platina) 

 crucible ; what remains dissolved in water ; the sulphuric acid preci- 

 pitated by baryta water ; and the new liquid, being filtered and eva- 

 porated, gives pure lithia. 



M. Quesneville very strongly recommends the use of nitrate of 

 lead in the analysis of alkaline minerals, according to M. Berthier's 

 proposal*. 



16. ON THE SUBMURIATES OF IRON, AND OTHER SUBSALTS. 



(Mr. Phillips.) 



Whilst dissolving moist precipitated peroxide of iron in muriatic 

 acid, Mr. Phillips observed that much more oxide was taken up than 

 he had expected, and, after repeated additions, he obtained a very 

 deep red-coloured solution, having little of the well-known chalybeate 

 taste, and of the s. g. of 1.017 ; it was not decomposed by the addi- 

 tion of water, or by heat, unless evaporated to dryness: alkalies 

 decomposed it. 'Ferroprussiate of potash gave a dark brown-green 

 precipitate. When more oxide was added, the excess, or a portion 

 of it, combined with the submuriate already formed, and the acid and 

 oxide were totally precipitated, forming another but an insoluble sub- 

 muriate. Even the addition of muriatic acid caused a partial decom- 

 position of the soluble submuriate, and a precipitation occurred : this 

 happens with no other binary salt. 



Being analysed, the soluble submuriate gave 37 muriatic acid and 

 382 of peroxide of iron, equal to one atom of muriatic acid and 9J 

 of peroxide. Mr. Phillips is inclined to consider 1 : 10 as the true 

 proportion. 



Except the subacetate of lead, this is the only subsalt so largely 

 soluble in water ; probably, the only one which contains so small an 

 atomic proportion of acid ; the only one decomposed by addition of 

 either acid or base : and the last mentioned point shows that there 

 are two other submuriates of iron differing from this one, by insolu- 

 bility in water. 



Mr. Phillips has also analysed the submuriate of antimony, or 

 powder of Algaroth. It consists of protoxide of antimony 92.45, 

 muriatic acid 7.8 ; or 9 atoms and 1. 



Subnitrate of bismuth was also analysed, and proved to consist of 

 81.92 oxide of bismuth, and 18.36 nitric acid ; or 3 atoms and 1. 



Submuriate, or magistery of bismuth, being analysed, gave 87 

 oxide of bismuth, and 13.6 muriatic acid; or 3 atoms and 1. Ac 



* Journ. de Pharm. 1830, p. 1196. 



