136 HEINRICH ROSE ON THE COMBINATIONS OF 



This answers to the chemical formula 9 C + 4 NTP + 10 H, 

 or, 9C + 4NH'* + 6H. Calculated accordingly, the compo- 

 sition would be, 



Ammonia 19"19 



Carbonic acid 55*65 



Water 25-16 



100-00 

 0-866 grm. of beautifiil crystals prepared on another occasion 

 gave 0-920 grm. metallic platina, which corresponds to 18-47 

 per cent, ammonia in the salt. 



It is necessary to determine, in the analysis, the quantities of 

 ammonia and carbonic acid from the same portion of crystals. 

 I examined some transparent crystalUne incrustation of a differ- 

 ent portion, only for carbonic acid, as I obtained but a small 

 quantity of them in a pure state : 0-664 grm. gave 192-29 cub. 

 centim. carbonic acid gas by means of muriatic acid, which 

 answers to 57-33 per cent, carbonic acid. Perhaps this crust 

 might have been the f carbonate of ammonia with a different 

 quantity of water ; for if we only suppose 9 atoms of water, in- 

 stead of 10, in the salt, which, in fact, is a more probable amount 

 of water, then it would contain. 



Ammonia 19-68 



Carbonic acid 57-09 



Water 23-23 



100-00 

 The I carbonate of ammonia is only produced by the ac- 

 tion of sulphuric acid on a solution of the sesquicarbonate. 

 Whilst it changes into the bicai'bonate by the loss of neutral 

 carbonate of ammonia, the ammonia alone of this last is absorbed 

 by the sulphuric acid, the surface of which becomes covered 

 with a strong efflorescence of sulphate oxide of ammonium, and 

 the carbonic acid gradually combines with the bicarbonate. If 

 the pumping is performed rather quickly bicarbonate only is 

 formed, under the above-mentioned circumstances, from the ses- 

 quicarbonate, because the carbonic acid is then too rapidly re- 

 moved. Also, on employing hydrate of potash, lime, or even 

 chloride of calcium, instead of sulphuric acid, bicarbonate only 

 is produced ; the chloride of calcium absorbs the carbonate of 



