158 Miscellaneous Intelligence. 



itself to the tube, having the same colour as the copper, and, in 

 one place,.even its metallic splendour. The heat was continued 

 for three quarters of an hour, during which time the matter in 

 the tube remained unchanged. A copper wire thus heated be- 

 ing withdrawn from the tube, and moistened, became slightly 

 blue after some time, and the sublimate in the tube underwent 

 the same change slowly in the air. Another tube, with its 

 copper contents left exposed to the air alone, became brown 

 and blue in different parts. 



Sig. Fusinieri deduces from these results, that dry ammoniacal 

 gas combines with copper, by the aid of heat, the compound 

 being volatile, and retains the colours of the metal, though it 

 be more pale. Also, that the formation happens without the 

 production of colours ; and also, that this dry ammoniuret of 

 copper has the power of decomposing water, of oxydizing the 

 metal, and then of forming the common blue ammoniuret.— 

 Giornale di Fisica. 



These conclusions do not come with much force to our minds; 

 but we insert the experiment at this time, because chemists 

 are anxiously looking to nitrogen and its compounds for some 

 results illustrative of its nature. — Ed. 



9. Estimation of Carbonic Acid in Mineral Waters. — \i is 

 frequently an object in the analysis of mineral waters, to ascer- 

 tain the quantity of carbonic acid in them ; and for this, seve- 

 ral processes are recommended. Among others, is that of 

 boiling the water in a retort or flask, and passing the gas libe- 

 rated from it through a solution of muriate of lime, or barytes 

 to which ammonia has been added ; the quantity of carbonate 

 thrown down being the indication of the quantity of carbonic 

 acid from the water. 



Dr. Vogel of Munich, however, finds the process very faulty, 

 from the circumstance of its not indicating small quantities. 

 Three or four cubic inches of carbonic acid gas, added to one 

 ounce of ammonia, and this to a solution of one part of muriate 

 of baryta in nine of water, produced no change. Precipitation 

 would begin only on adding more carbonic acid, or on boiling. 

 An ammoniacal muriate of baryta, added to carbonic acid gas, 

 over mercury, caused no precipitation, by the absorption of 

 the first two or three inches of gas ; and when the precipitate, 

 caused by a further absorption of gas, had been filtered 

 out from the liquid, more was obtained by ebullition. Only 



