402 Intelligence and Miscellaneous Articles. 



This composition is the same as that which MM. Mulder, Link and 

 Hochstetter have found to exist in the different ceruses of commerce. 



The author states that some comparative trials made by artists, 

 have satisfied him that this new ceruse covers as well as those of the 

 best manufactures in France, and it is less hurtful to workmen than 

 the common operation. — Comptes Rendus, September 4, 184S. 



META-ANTIMON1ATE OF AMMONIA. BY M. E. FREMY. 



The author observes that this salt has not hitherto been described 

 by any chemist. It was prepared by first precipitating, with a great 

 quantity of water, very pure perchloride of antimony, in order to 

 obtain hydrated meta-antimonic acid ; this acid was allowed to re- 

 main during several weeks in a concentrated solution of ammonia. 



The meta-antimonic acid dissolved slowly in the ammonia, and pro- 

 duced a meta-antimoniate of ammonia, containing one equivalent 

 of acid and two equivalents of ammonia, corresponding to the bibasic 

 salt of potash, Sb 2 O 3 , 2KO. 



The bibasic meta-antimoniate of ammonia appears difficult to se- 

 parate ; but when a few drops of alcohol are added to the aqueous 

 solution, a crystalline salt is precipitated containing one equivalent 

 of acid and one of base, and corresponding to the acid meta-anti- 

 moniate of potash. 



It yielded by analysis 68*1 per cent, of meta-antimonic acid ; repre- 

 senting the meta-antimoniate of ammonia by the formula Sb 2 O, 

 Az H 3 , HO-f- 6HO, theory gives 5"6 per cent, of azote, 68-2 of meta- 

 antimonic acid, and 4'0 of hydrogen. 



This salt contains one equivalent of water less than the meta-an- 

 timoniate of potash, Sb 2 O 3 , KO, 7HO. This partial loss of water 

 is probably owing to the alcohol employed to precipitate the ammo- 

 niacal salt. 



The meta-antimoniate of ammonia may be employed to charac- 

 terise the salts of soda ; for it precipitates this base from its solutions 

 with the same facility as the meta-antimoniate of potash. 



The author observes, that he has before stated that the antimo- 

 niate of potash completely loses its solubility in water by being ren- 

 dered anhydrous ; the meta-antimoniate of ammonia undergoes a 

 similar transformation, becoming also almost insoluble by losing a 

 part of its water ; this effect is produced by subjecting it to a very 

 slight increase of temperature. 



When this salt is boiled in water, it loses its crystalline appearance 

 and becomes a white powder, which is the insoluble antimoniate of 

 ammonia ; in this case no trace of ammonia is given out. 



When antimonic or meta-antimonic acid is dissolved with heat in 

 ammonia, it is always the insoluble antimoniate of ammonia which 

 separates on cooling : the crystalline meta-antimoniate of ammonia 

 can be obtained only by the cold digestion of the meta-antimonic 

 acid in ammonia ; yet it sometimes happens that a large proportion 

 of the meta-antimoniate changes into amorphous antimoniate of am- 

 monia. This loss of water appears to be produced when too great 

 an excess of ammonia is employed. The meta-antimoniate of am- 



