516 -v^ Messrs. Playfair und Joule ow^o^k 



solution of ammonia to nitrate of mercury, and was of a pure 

 milk-white colour, as described by Kane. On throwing 40 

 grains of this compound into water, an increase of 6' 7 "vyas 

 obtained ; this gives a volume of 67'0 on the equivalent, ap|| 

 5is970 as the specific gravity of the salt. 

 n Chloride of Copper, CuCl=67'l8. — The volume of hydrat?^ 

 chloride of copper was shown to be 33 or 3 x 11 ; but we have 

 not yet examined the bulk occupied by the anhydrous chlo- 

 ride. The chloride was deprived of its water by a heat con- 

 siderably below that of redness, in order to prevent the forma- 

 tion of any sub-chloride. On throwing 33*59 grains, or half 

 an equivalent, into turpentine, the increase in two experiments 

 was exactly 11*0, which gives 22-0 as the volume of the salt, 

 and 3*054 as its specific gravity. 



Ammonia-Chloride of Copper, CuCl + 2NH3 + HO = 1 10*3. 

 — This salt was made by passing a stream of ammonia through 

 a solution of chloride of copper until the precipitate formed 

 had completely redissolved. The crystals, which deposited as 

 the solution cooled^ were dried in a receiver containing slaked 

 lime, so as to prevent the carbonic acid of the atmosphere 

 acting upon the ammonia ; but in spite of this precaution the 

 crystals had slightly effloresced on the surface. The efflo- 

 resced matter was removed, and the pure crystals employed. 

 27'6 grains of them, when thrown into turpentine, produced 

 in two experiments an increase of 16*5, making the volume 

 of the salt 66*0, and its specific gravity 1*672. On dissolving 

 the same quantity of salt, 27*6 grains, in 1000 grains of water, 

 the rise was 15*9 at 62°, making the volume of the salt when 

 in solution 63*6. 



On exposing this salt to heat, water and ammonia are ex- 

 pelled, and a green powder remains, having the formula CuCl 

 4-NH3. 21*07 grains of this salt thrown into turpentine pro- 

 duced an increase of 9' 6, making the volume of the equiva- 

 lent 38*4, and the specific gravity of the salt 2*194. 



Subchloride of Copper, CugCl = 98*89. — The subchloride 

 used in the experiment was made by adding protochloride of 

 tin to a solution of chloride of copper. During the desicca- 

 tion of the salt it became slightly green, showing that a little 

 chloride had been formed by the absorption of oxygen ; but 

 the change was so slight as probably not to interfere mate- 

 rially with the result ; 42*2 grains, thrown into turpentine, 

 caused an increase of 12*5, which gives 29*2 as the volume, 

 and 3*376 as the specific gravity of the salt. 



Subchloride of Mercury, Hg2Cl= 238*33. — The fourth part 

 of an equivalent, 59*58 grains, thrown into turpentine, caused 

 an increase of 8*3. 



