1888.] Prafulla Chandra Ray on Copper- Magnesium Croup. 271 
tion was made by mixing in equivalent proportions previously pre- 
pared double sulphates of copper-potassium (CuSO^. K2SO4. 6H2O) 
and magnesium-potassium (MgSO^. K2SO4. 6H2O). Ror the 
preparation of these double sulphates I am indebted to Mr Andrew 
King. Only one crop was collected. 
YIII. Copper-Kickel-Potassium Sulphate. — Unknown quantities 
of the double salts previously prepared, as in the preceding case, 
were dissolved in water. One crop only was collected. 
IX. Copper-Kickel-Potassium Sulphate. — Sulphate of copper 
and sulphate of nickel were weighed out in equivalent proportions, 
and dissolved in water along with the calculated quantity of 
potassium sulphate. 
X. Copper-Cadmium-Ammonium Sulphate. — The component 
salts for this preparation were mixed in equivalent proportions. 
One crop only was collected. The copper was separated as in IX. 
The cadmium was estimated as sulphide. 
XI. Copper- Cadmium- Ammonium Sulphate. — For this pre- 
paration the sulphates of copper and cadmium were mixed in the 
equivalent ratios 1:4. 10 grammes (‘04 equivalent = 9 ‘98) copper 
sulphate and 41 grammes (T6 equivalent = 40*96) cadmium 
sulphate were taken and dissolved together, with the calculated 
quantity of ammonium sulphate (27 grammes). The copper and 
cadmium were estimated as in X. 
XII. Nickel-Iron-Potassium Sulphate. — The component sul- 
phates were mixed in equivalent proportions. In the analysis the 
iron was separated as basic acetate. 
XIII. Xickel-Iron-Potassium Sulphate. — The sulphates of 
nickel and iron were taken in the equivalent ratio 1:4. 11 grammes 
(*04 equivalent = 11*22) nickel sulphate and 44*5 grammes (*16 
equivalent = 44*48) iron sulphate were dissolved together, with the 
calculated quantity of potassium sulphate. 
XIV. Iron-Cadmium-Ammonium Sulphate. — The component 
sulphates were mixed in equivalent proportions. Only one crop 
was collected. 
XV. Iron - Manganese - Ammonium Sulphate. — 14 grammes 
(*05 equivalent = 13*9) ferrous sulphate were mixed with 12 
grammes (*05 equivalent = 12*05) manganese sulphate and the 
calculated quantity of ammonium sulphate. One crop was collected. 
VOL. XV. 10/11/88 s 
