120 HEINRICH ROSE ON THE COMBINATIONS OF 



by ammonia, after having been treated with chloride of barium, 

 and the precipitated mass filtered. 



The salt in the retort continually becomes moister, whilst the 

 sublimate in the neck of the retort increases, and begins to be 

 deposited in the body of the retort. At last a clear liquid only 

 is left in the retort, from which, when the heat is over, a 

 salt crystalhzes, in the form of tables, in great quantity. The 

 bulb of the retort must be broken, in order that the crystals may 

 be well separated and obtained pure from the original mass. 

 If the mass is preserved for a long time in closed vessels, a 

 quantity of tables of the same salt is deposited from it, of more 

 beautiful and distinct crystalline stinicture. This deposition of 

 crystals continues for some weeks. When it ceases, the mass 

 contains only neutral carbonate of ammonia in solution ; by means 

 of a solution of chloride of barium it is thrown down so com- 

 pletely, that ammonia produces no precipitate in the filtered li- 

 quid. 



The salt sublimed in the neck and in the body of the retort, 

 as well as that ciystallized from the solution, are two combina- 

 tions hitherto unknown. This sublimed salt will be treated of in 

 the following section. 



The crystals of the salt from the solution have the form of 

 thin six-sided plates. On account of their thinness and rapid 

 efflorescence the angles could not be measured. No cleavage 

 could be obsei-ved. 



Since this salt may be obtained in distinct crystals, it is con- 

 sequently free from foreign mixtures ; and the various analyses 

 agree better with one another than is the case with those of the 

 sublimed and non-crystalline combinations of carbonic acid with 

 ammonia, and are more in unison with the calculated result. 

 1'904 grm. gave 2*594 grm. of metallic platina ; 1*816 grm., with a 

 solution of chloride of barium, treated with an addition of am- 

 monia, gave 3*674 grm. of carbonate of barytes. This corresponds 

 to the following composition : 



Ammonia 23*69 



Carbonic acid 45*35 



Water 30*96 



100*00 



