p. C. Ray — On Mercurous Nitrite, 



[No I 



sulphite, thorouglily washed with hot water, dried and re-washed with 

 carbon bisulphide, purified by being kept over mercury and re-distilled. 

 Unless the precipitate is treated once more with carbon bisulphide, the 

 result is apt to be too high. There is thus not much to choose between 

 these methods. Both, however, give satisfactory results when conduct- 

 ed with care and patience. 



Prep'iration 1. — 0"8695 gram. substancG gave 0'274 gram, "free" 

 mercury = 31 "5 per cent. " free " mercury. 1*1895 gram, substance kept 

 over Hg SO^ in the dessicator ; July 27th 1895. July 30th, wt. = l-18i 

 gram.; after a month's stay in the dessicator, the vvt. was constant = 

 1'184 gram. l*181i gram, substance gave 0*3485 gram. " free " Hg, = 

 29"43 per cent, "free" Hg ; 0246 gram. HggClg from the ou5 salt in 

 solution = 177 per cent. Hg. ; and 0'422 gram. HggClg from the zc- salt 

 = 30-27 percent. Hg. 



Preparation II. — 1*2865 gram, substance gave 0'3957 gram. " free " 

 Hg,=30-76 per cent.; 0*25 gram. HggClg from the ou^ salt = 16-5per 

 cent. Hg ; and 0"4645 gram. HggClg from the ic salt = 30-69 per cent. 

 Hg. 1*224 gram, substance gave 0*3575 gram. " free " Hg, = 29*2 per 

 cent.; 0*243 gram. HggClg from the ous portion = 16-86 per cent. Hg ; 

 and 0-437 gram. HgnClg from the ic portion = 30-31 per cent. Hg. 



Preparation III. — 1-6 tl gram, substance gave 0-5025 gram, "free " 

 Hg, = 30'62 per cent.; 0348 gram. HggClg from the ous salt = 17*8 



H< 



and 0-5965 gram. HgS from the ic salt = 31-33 pei 



per cent, 

 cent. Hg. 



The results are presented here in a tabulated form for convenience 

 of I'eferenee. 





" Free " 



Mercury 



Mercury 



Total 







Mercury. 



in the 

 ic Salt. 



in the 

 ous Salt. 



per cent, of 

 Mercury, 





1. 



31*5 





... 



... 





2. 



[29-43] 



30*27 



17-7 



78-67 



^ 



'-0 



3. 



30-76 



30-69 



16-5 



77-95 





60 



4. 



[29-2] 



30-31 



1686 



77-87 







5. 



30-62 



31-33 



17-8 



7975 



J 



a 



Tiie percentage of " free mercury " in analyis (2) and (4) respectively 

 comes out too low. The cause of this has been already explained. 



