| The crude sulphide is rectified by redistillation over zinc or perchloride of mercury by means of a steam or water bath. |
| Sterilized vaseline or glycerine of perchloride of mercury may be smeared over the point of the dilator to facilitate its passage. |
| Add ammonia to a solution of perchloride of iron as long as the precipitate formed is redissolved. |
| If the perchloride is employed it should remain in contact with the crude sulphide for at least 24 hours before redistillation. |
| In the second week of therapy, the patient became normokalemic without support of oral potassium perchloride. |
| If for any reason they are preferred, the perchloride of iron is one of the very best preparations. |
