384 Foreign and Miscellaneous Intelligence. 



proportion to form water, there remains the following composition 

 as nearly as may be : 



4 vols. carbon 27.08 



2 azote 32.02 



2 oxygen 36.36 



4 hydrogen 4.54 



100. 



Oxamide may, therefore, be considered at pleasure as a compound 

 of cyanogen and water ; or as a compound of deutoxide of azote, 

 and bicarburetted hydrogen ; or as a compound of oxide of carbon 

 and a hydruret of azote, different to ammonia. Whichever way it 

 be viewed, if 2 volumes of vapour of water are added to it, dry 

 oxalate of ammonia is produced ; and it is in this way, apparently, 

 that sulphuric acid and potassa act. 



In conclusion M. Dulong remarks, that many animal matters, as 

 albumen, gelatine, fibrine, &c., act with potassa as oxamide does. 

 Uric acid approximates to it : hippuric acid also resembles it. All 

 these bodies have properties in common with it so characteristic, that 

 M. Dulong has been induced to commence an experimental com- 

 parison of them with this new substance *. 



9. PREPARATION OF NITROGEN. (Professor Emmett.) 



When zinc is dipped into fused nitrate of ammonia, it is instantly 

 oxidized and dissolved, and nitrogen and ammoniacal gases are 

 evolved. The zinc disappears with as much rapidity as when ex- 

 posed to the strongest mineral acids ; and, at the same time, so com- 

 pletely sustains the requisite temperature, that it becomes unnecessary 

 to continue the application of heat after the action commences. The 

 heat required is 280 or 300, but a small piece of zinc soon elevates 

 it to 540. No nitrous or nitric oxide could be detected in the 

 evolved gas, and therefore Professor Emmett recommends the 

 operation as one well fitted to supply nitrogen gas. 



A tubulated retort is to be partly filled with the nitrate of am- 

 monia, and a cork fitted to the tubulature. Through this cork is to 

 pass freely either a knitting-needle or an iron wire, holding, by means 

 of a hook, the coil of zinc. As soon as the salt has entered into 

 fusion, the knitting-needle must be pushed down far enough to 

 place the zinc in contact with the nitrate. This arrangement is not 

 only convenient but necessary ; for if the zinc be thrown at once 

 into the fused salt, the action will prove too violent and unmanage- 

 able ; whereas, when contact is not constantly maintained, there is a 

 strong tendency towards a vacuum in the retort, which would 

 endanger its safety. By the process here recommended, there is no 

 liability to accident, and the quantity of nitrogen may be easily 



* Ann. de Chimie, xliv, 113, 



