Characters. - Like the tersulphate; but on mixing two volumes of the solution with one of concentrated sulphuric acid a solid white mass separates on standing.

Dose. - 3 to 10 minims (.18 - .64 c.c).

Action. - Astringent, styptic, haematinic Less irritating than the tersulphate.

Uses. - Like the chloride. It is a useful astringent in relaxed sore-throat and tonsillitis.