Determination of Nitrogen in Organic Compounds. 253 



Art. VI. — A New Method of determining the quantity of Nitro- 

 gen in Organic Compounds ; by Drs. Varrentrapp and Will. 

 Translated from the original in the Annalen der Chemie und 

 Pharniacie, by J. Lawrence Smith, M. D. of Charleston, S. C. 



Messrs. Editors — In this letter I send you a translation of such 

 parts of the original article of Drs, V. and W. as may enable one 

 to thoroughly understand this valuable addition to what is already 

 known upon the subject of organic analyses ; neither the first nor 

 the latter parts are here taken notice of, as the one is merely a 

 detached account of the various processes that have been pre- 

 viously employed to estimate the quantity of nitrogen in organic 

 compounds, and the other, the mention of some analyses made 

 with the view of comparison. 



" This method has for its basis the peculiar action of the hy- 

 drated fixed alkalies, upon organic substances containing nitrogen, 

 when subjected to a high temperature. It consists in the separa- 

 tion of nitrogen in the form of ammonia, and estimating the lat- 

 ter, either under the form of the muriate of platinum and ammo- 

 nia, or from metallic platinum." 



" If one melts an organic substance free from nitrogen, together 

 with the hydrate of potash, the v/ater of the potash becomes de- 

 composed, (as Gay Lussac has shown,) its oxygen combines 

 with the carbon and hydrogen of the organic matter, and its 

 hydrogen passes off in the form of gas." 



For a perfect result of the above nature a high temperature is 

 required, as well as a considerable excess of potash. 



" When on the contrary, the organic substance contains nitro- 

 gen, the free hydrogen combines with it and forms ammonia. 

 Since the observation of this fact, the only use that it has been 

 put to, has been that of ascertaining the presence of nitrogen in 

 an organic compound." 



The first and chief difficulty that presented itself to Drs. V. 

 and W. in making use of this method to estimate the quantity 

 of nitrogen, was that when a substance was very rich in that 

 element, the whole of it would not be converted into ammo- 

 nia, but that a portion by combining with the carbon formed 

 cyanogen, which would pass off or be converted into hydrocyanic 

 acid, and the latter unite itself to the potash. But upon experi- 



