482 P. 0. Ray — Mercurous Nitrite and its Derivatives. [No. 4, 



they are oxychlorides of mercury and the presence of sodium chloride 

 is a sine qua non for their formation, and the only yield is one of sodium 

 nitrate. But this last compound has sometimes been observed as the 

 sole product without the formation of the former, even in presence of 

 an excess of sodium chloride. The reaction goes on very slowly, and it 

 takes a month and upwards to complete it. 



Analysis and general properties of the red and iodine-like lustrous 

 scales :— 



(1) 0-3505 g. gave 03485 HgS. 



(2) 0- 465 „ „ 0- 455 „ 



(3) 05086 „ „ 0-2034 AgCl. 



(4) 06166 „ „ 21-1 c.c. moist O at 31° C. and 752 mm. 



pressure. 



Theory for Theory for Found 



„.> . 



Hg Cl 8 . 2 HgO Hg Cl 2 . 2 HgO. } H^O i ii 



Hg 85-35 84-27 84-45 84*34 



CI 10-10 9-97 9-90 



O 455 4-50 4-17 



H,0 1-26 



100-00 10000 



The analyses recorded above are of distinct preparations, and they 

 conform to the formula HgCl ?/ 2 HgO. % H 2 0. 



These salts do not lose in weight when kept in a dessicator over 

 strong sulphuric acid or placed in a steam chamber at 100° C. When 

 heated in a bulb-tube a deposit of moisture is invariably noticed, and 

 a sublimate of mercurous and mercuric chloride obtained, with a 

 residue of orange-yellow oxide. Treated with caustic soda solution, 

 the dark variety changes to orange-yellow. 



Millon, and more recently Thummel (Archiv. Pharm.§ [3], 27, 

 589-605) have exhaustively studied the oxychlorides of mercury, and 

 have described several of them. These were obtained, however, by 

 adding together solutions of mercuric chloride and hydrogen potassium 

 carbonate under varying conditions. Yolhard got shining dark crystals 

 by the action of sodium acetate upon corrosive sublimate solution 

 (Annalen : 255, p. 252) ; whilst Haack obtained a reddish-brown crys- 

 talline deposit by treating mercuric chloride with phosphate of sodium 

 (ibid. 262, 189), all of the formula HgCl 2 . 2 HgO. The red and black 

 shiuing compounds, the subject of the present paper, agree in general 



§ The Original Memoir is not available here. I am quoting from Watt's Diot. 

 of Chem., New Ed. See also Abs. Chem. Soc. Joarn., Vol. LVI, 1050. 



