1900.] P. C. Ray — Mercurous Nitrite and its Derivatives, 483 



properties with those obtained by the above chemists ; but the hydrated 

 modifications I do not find mentioned anywhere. 



I. 



Mercurous Nitrite and Silver Nitrite. 



A. Concentrated solutions of mercurous nitrite and silver nitrite. 



As both mercurous nitrite and silver nitrite are very sparingly 



soluble in cold water, the solutions used were always kent at about 



100° c. 



Method of experiment : — To the hot or boiling solution of mercurous 

 nitrite containing necessarily mercuric nitrite was added the solution of 

 silver nitrite. No effervescence due to the evolution of gases was 

 noticed, and the liquid which at once became cloudy on account of the 

 separation of metallic mercury, was allowed to stand over night. Next 

 day a perfectly clear solution was obtained, with a deposit of mercury 

 and silver in successive layers at the bottom of the vessel, — the lower 

 one of dirty grey mercury, and the upper one of an arborescent and 

 filamentous growth of shining minute crystals of silver. These metals 

 were estimated in the usual way. The strength of the filtrate was 

 determined by finding out the weights of the ous and ic mercury as well 

 as that of silver in solution. Control analyses were also simultaneously 

 made to ascertain the original strengths of the mercury and silver 

 nitrite solutions under exactly similar conditions of temperature. For 

 details see Table of Analyses. 



In order to estimate the total amount of nitrogen and the trans- 

 formation, if any, of the nitrite into nitrate, or any other compound of 

 nitrogen, the following method of analysis as exemplified in Exp. I was 

 adopted. 



50 c.c. of mercurous and mercuric nitrite solution were boiled for 

 a few minutes with an excess of caustic soda ; 25 c.c. of silver nitrite 

 solution were also similarly treated. The filtrates from the mercury 

 and silver precipitates, containing nitrogen in the shape of nitrite of 

 sodium, were now added together and made up to a given volume. 

 After the interaction of mercurous and silver nitrite solution, an aliquot 

 portion of it was boiled with the alkali, and the filtrate set aside as above. 

 The nitrogen in both the cases was estimated by the Crum-Frankland 

 process, as also by the Urea method as worked out by Percy Frankland. 

 As a further check a few c.c.'s were in certain instances evaporated to 

 dryness in a porcelain boat and the nitrogen determined by Dumas' 

 method. It is remarkable that the sum total of nitrogen as found by 

 all these different methods was exactly the same, proving that not only 

 was there no loss of nitrogen during the reaction but that it remained ill 



