Method of preparing pure Oxide of Antimony. 223 



with nitrate of silver. It is therefore advisable to boil the 

 sponge several times in distilled water previous to dissolvino- 

 It in aqua regia. We consider it more simple, and as afford- 

 ing more accurate results, to weigh the nitrogen in the form 

 ot the ammonio-chloride of platinum, as in this case we have 

 tor every 177 parts of nitrogen 27SS parts of the salt on the 

 balance, but with metallic platinum only 1233 parts for the 

 same quantity of nitrogen. The error in weighino- must con- 

 sequently be double as great to exert the same mfluence on 

 the result. The weight of the ammonio-chloride remains 

 constant even when desiccation at 100° is continued for a 

 considerable length of lime, and the filter does not vary in the 

 least it previously well washed ; but when it contains a trace 

 ot tree acid the paper becomes black and friable. 



[The authors have tested the accuracy of this method on 

 various nitrogenous compounds, and a comparison of the re- 

 sults with those obtained by former methods will convince 

 ^rA-r\r"^T°^/^' superiority. We give at present but a i^^^ 

 ot MAI. Will and Varrentrapp's analyses of well-known sub- 

 stances, reserving others, for which new formula have been 

 advanced, for our next communication.] 



PROPORTION OF NITROGEN. 



TTroo .a^c ^x^ According to Calculated. 



U'^f^ •.•; ^^6-79 . . Woehler.ScLiebig 46-73 . 46-76 



J^"'^-:^^'^' 33-18 . . Liebig I33.36 . 33-37 



■laur'n H-OO . . Demarcay 11-99 n.27 



^^f;"^'^^ 31-7 . . Dumas' 31-85 '. 31-8 



^^ff^'" 28-90 . . Liebig 28-78 . 28-83 



Asparagin ...21-27 . . Liebig 21-17 21-27 



Melamin..... 66-22 . . Liebig 66-67 \ 66'56 



Hippuricacid 778 . . Liebig 7.39 7.32 



Amygdalin... 3-12-2-96 Wcehler& Liebig 3-07.' 3-07 

 {Ann. der Chem. und Pharm. xxxix. p. 257.) 



Method of preparing pure Oxide of Antimony. 

 The following is, according to Adolph Rose, the best me- 

 thod of preparing pure oxide of antimony :-One part of finely 

 powdered pure sulphuret of antimony is dissolved in 3i parts 

 of turning hydrochloric acid in a retort, and the clear solution 

 subjected to distillation. The first portion which passes over 

 IS set aside, as It contains nearly pure hydrochloric acid, and 

 as soon as the liquid which comes over becomes milky on the 

 addition o( water it is received separately. The distillation 

 s discontinued when no more passes over at a moderate heat, 

 the contents ot the receiver diluted with water, and the ;../r;/ 

 Algarotht decouiposed with a solution of carbonate of soda 



