Probably the widest field is still in the purification of iron and steel.
After purification he was sent by the Pythia to serve Eurystheus.
The whole history of the Jewish religion is centred in the gradual purification of the idea of God.
Here their use is likely to be limited by its costliness, because for the great majority of purposes the superiority of the electrically purified steel is not worth the cost of the electric purification.
The vessel, however, which contains this mixture has to be of earthenware, porcelain or enamelled iron on account of the free acid present; the gas must be washed after purification to remove traces of hydrochloric acid, and care must be taken to prevent the complete neutralization of the acid by the ammonia present in the gas.
