Vetere anes 
50 M. Grotthuss on separating Fron from Manganese. (Jan. 
gr. metal + 0°512 gr. oxygen = 3°07 gr. is subtracted from the 
sum total of hydrate, we obtain the quantity of acid ; but 458 
— 3:07 = 1°51, which must be the amount of the acid. These 
1:51 gr. of acid must contain 0-067 hydrogen, because this is the 
quantity requisite to convert 0°512 gr. of oxygen into 0°578 gr. 
of water. Hence it follows that 4-580 gr. of anthrazothionhydrate 
of copper contain 2°56 gr. of copper, 1-510 gr. of anthrazothionic 
acid, and 0-512 gr. of oxygen, or according to the accurate way 
of viewing this compound, that not the acid but the anthrazothion 
is united with the metal and with the water, the constituents 
are, 
Copper. “eis ais... 2°560 
Anthrazothion..., 1:442 (= 1:510 acid — 0-067 hydrogen) 
Wate ale ieinocss wis 0:578 (= 0°51] oxygen + 0:067 hydrogen) 
4-580 
or in 100 parts, 
OD ADED Cees cia: word geaiane wate 55°89 
Anthrazothion ,........... 31:48 
WER, sicic'y cid gen eireien is eo AQ68 
100-00 vee 
(To be continued.) 
Articte VII. 
A Method of separating Iron from Manganese. 
By Theodor von Grotthuss.* 
Dissoxve the metal, or the oxide, in muriatic acid ; and as it 
is necessary to convert the iron into a peroxide, pour a few drops 
of nitric acid mto the solution, and evaporate it till it becomes 
doughy and merely moist. Pour over it, when in this state, a so- 
lution of anthrazothioniate of potash inalcohol, and mix the whole 
well together. The liquid becomes immediately of a blood red 
colour, because anthrazothionate of iron is formed which 
dissolves in the alcohol. The anthrazothionate of manganese 
falls down in the state of a white powder, because it is not soluble 
in absolute alcohol. Add a portion of alcohol, filter the liquid, © 
and wash the white insoluble anthrazothionate of manganese 
repeatedly with small portions of alcohol. It will be manifest 
that the manganese is quite freed from all admixture of iron when 
the alcohol comes off from it quite colourless. The oxide of iron 
may be precipitated from the red liquid by means of potash ley, 
* Translated from Schweigger’s Journal, xx. 272. 
