containing Copper, Zinc, and Nickel. 17 



follows that there was an excess of C0 2 equal to *259 gram in 

 every 10 cubic centims. of the original solution of commercial 

 carbonate. To neutralize this, 18 grams of ammonia were 

 required to be added to a litre of the commercial carbonate 

 solution. This was furnished by 61*7 cubic centims. of am- 

 monia solution (of sp. gr. '880). 



I next endeavoured to determine whether the nature of the 

 salt of nickel or cobalt has any effect on the reaction. For 

 this purpose the following solutions were prepared: — 



CoCl 2 . . 



1 cubic centim. 



= '00125 gram 



:C0. 



NiCl 2 . . 



1 cubic centim. 



= •0025 „ 



Ni. 



Ni(NO s ) 2 . 



1 cubic centim. 



= •0025 „ 



Ni. 



NiS0 4 . . 



1 cubic centim. 



= •0025 „ 



Ni. 



Co (NO,), . 



1 cubic centim. 



= •00125 „ 



Co. 



CoS0 4 . . 



1 cubic centim. 



= •00125 „ 



Co. 



The method of proceeding was as follows : — Into each of 

 five cylinders 25 cub. centims of the standard solution of 

 cobaltous chloride were placed ; to the first cylinder 39 cubic 

 centims. of the solution of nickelous chloride were added, to 

 the second cylinder 39*25 cubic centims., and so on, to the 

 fifth cylinder 40 cubic centims. of nickelous chloride being 

 added. Each cylinder was then made up to 100 cubic centims., 

 and 25 cubic centims. out of each 100 cubic centims. placed 

 in a second series of cylinders. To each of the second series 

 neutral ammonium carbonate (25 cubic centims.) was added, 

 and then sufficient water + o make 150 cubic centims. The 

 results are expressed in the following Table:- 



Cylinder. 



Co used. 



Ni used. 



Ratio of 



Colour. Ni to Co, 



1. ... 



2. ... 



3. ... 



4. ... 



5. ... 



. -03125 grm. 

 . -03125 „ 

 . -03125 „ 

 . -03125 „ 

 , -03125 „ 



■097500 grm. 

 •098125 „ 

 •098750 „ 

 •099375 „ 

 •lOCOOO „ 



Purple 3-12 

 Slightly purple. 3-14 

 Between 2 and 4. 3*16 

 Slightly blue 3-18 

 Blue. " 3-20 



In two experiments, using in the first solutions of CoCl 2 

 and XiS0 4 and in the second solutions of CoCl 2 and Ni(X0 3 ) 2 , 

 I obtained exactly the same results ; so that the foregoing 

 Table expresses the results of these experiments. Subsequently 

 experiments were made with the same quantities of the metal's 

 in the following combinations : — 



Co(X0 3 ), with NiS0 4 , Ni(NO s ) 2 and XiCl 2 . 

 CoS0 4 with Ni(N0 3 ) 2 , NiS0 4 and NiCl 2 . 



The results of these latter experiments were exactly the 

 same as those of the first experiments, so that the Table also 

 does equally well to express them. 



Phil Mag. S. 5. Vol. 6. No. 34. July 1878. C 



