727. White Vitriol
White Vitriol, or Sulphate of Zinc, is an astringent, tonic, and emetic.
It is
used externally
as a collyrium for ophthalmia (See
), and as a detergent for scrofulous ulcers, in the proportion of three grains of the salt to one ounce of water.
It is
used internally
in indigestion, and many other diseases;