ZlNCUM. 69 



Characters. Brilliant white, pearly, tabular 

 crystals, with an odour of valerianic acid, and a 

 metallic taste. Solubility, 1 in 120 of water ; 1 in 

 60 of spirit. 



Impurities. Sulphate and butyrate of zinc. 



Dose. 1 to 3 gr. 



Non-officinal Preparations of Zinc. 



Calamina Praeparata. Calamine. Impure 

 Oxide of Zinc, obtained by calcining native Car- 

 bonate of Zinc, and reducing it to an impalpable 

 powder. A greyish or flesh-coloured powder. 



Oleate of Zinc. Made by heating Oxide 

 of Zinc with Olcic Acid. 1 to 8. 



Incompatible* of Zinc Salts in general. 



Alkalies and their carbonates, lime-water, acetate of lead,! 

 nitrate of silver, astiingent vegetable infusions or decoctions,) 

 and milk. 



ACTION AND USES. 

 1. IMMEDIATE LOCAL ACTION AND USES. 



Externally. The salts of zinc closely resemble in their 

 action the salts of lead, silver, and copper, being caustic in their 

 stronger forms, astringent or antiphlogistic in their weaker 

 forms. Zinc presents every degree of this action, according to 

 the salt employed, that is probably according to the solubility 

 and diffusion-power of the particular combination of the mfltaL 

 Thus the chloride, which is highly deliquescent, penetrates tho 

 tissues, and is a powerful escharotic, causing destruction of the 

 part, with severe pain, separation of a slough, and subsequent 

 healing. It is employed to destroy morbid growths, oUronio 

 ulcers, and gangrenous parts, in the form of a paste or of solid 

 arrows made with plaster of Paris or flour, or as a strong 

 solution. The sulphate and acetate have less affinity for water, 

 and are much less powerful than the chloride. AVhen applied 

 to the broken skin, an ulcer, or an exposed mucous surface, they 

 precipitate the albuminous juices or secretions, coagulate tin- 

 protoplasm of the upper layers of growing cells, and indirectly 

 cause contraction of the vessels, though less than silver and 

 lead. The sulphate of zinc is the most common of all applica- 

 tions for healing ulcers and wounds, limiting the amount of 

 discharge, checking excessive or " weak " growth, and modify- 

 ing the intensity of the inflammatory process with which tho 



