The alumina may be separated from the ferric oxide by potash-lye.
If present, ferric ferrocyanide, a blue precipitate, will be formed.
From a mixture of muriate of iron (ferric chloride) and spirit of tar.
It has a bitter taste and acid reaction; its aqueous solution is unaffected by the ferric salts and tincture of galls.
The liquors are previously mixed with a little milk ...