160 T. H. LABY. 
confirmatory results are given. Engels’ states that nickel 
may be deposited free from iron if the latter is thoroughly 
oxidised by hydrogen peroxide. Foerster’ finds iron to be 
deposited. Ducru’ obtains the nickel, cobalt and iron (ferric) 
as sulphates, and electrolyses in the presence of the ferric 
hydrate precipitated by the free ammonia present. An 
irregular amount of iron, about °5% of the total present is 
deposited with the nickel, partially insoluble in concen- 
trated hydrochloric acid. Using the usual sulphate solution 
Neumann finds, contrary to Engels and Ducru, that with 
varying conditions of time and strength of current a quite 
irregular amount of iron is deposited (if more than ‘1 gram 
of iron as ferric hydrate is present) which is tedious and 
inaccurate to determine volumetrically. 
6. The Ether Process. 
The solubility of ferric chloride, and insolubility of man- 
ganous, nickelous, chromic and aluminium chlorides in ether 
in the presence of hydrochloric acid was pointed out by 
Rothe’ in 1892, who used it as a means of separating iron 
from cobalt, copper and these metals. Copper and cobalt 
partly in solution in the ether may be removed by shaking 
out the ether with 5°8 H. (8.G. 1°104) hydrochloric acid. A 
modification ° of this is the solution of the chlorides (‘4 grm.) 
in a minimum of water and 10.cc. of concentrated hydro- 
chloric acid, the addition of 10 cc. of ether and the passing 
into it of hydrochloric acid gas at 0° C. The nickel is pre- 
cipitated as the yellow chloride; the iron and cobalt are in 
solution. Adaptations for technical work, nickel steel and 
ores, have been published. Langmuir’ precipitates the iron 
1 Journ. Chem. Soc., Abs. 1898, ii., 192 Rundschau, 1896, 20-24. 
? Ibid., p. 228. 
$ Bull. Soe. Chim.. [8] xvut., (1897). 
* Chem. Zeit., 1898, xx11., [72] 731 -— 732. 
> Abst. in C.N. 1892, txvi., 182, Mitth. a. d. kgl. Tech. Versuchs. 
Anstalen, Berlin. : 
6 Pinerua, CN. 1897, pxxv. 193. 
7 Langmuir—Journ. Am. Chem. Soc. xx11., 1900. 
