248 SILVER NITRATE 



a water-bath until the mixture assumes a brown colour. 

 It is employed as a dressing for open joint, for thrush, 

 canker, and other foot cases. 



SILVER AND ITS MEDICINAL COMPOUNDS 



SILVER NITRATE. Argenti Nitras. Lunar Caustic. Lapis 

 Infernalis. AgN0 3 . 



When metallic silver is gently heated with diluted nitric 

 acid, and the solution evaporated, silver nitrate crystallises 

 in colourless right rhombic prisms. To form the familiar 

 sticks or pencils, the salt is fused and run into moulds. 

 Toughened caustic is prepared by adding, before fusion, one 

 part potassium nitrate to nineteen parts silver nitrate. 

 Mitigated caustic is made by fusing together one part of 

 silver nitrate, and two parts of potassium nitrate, and 

 pouring into moulds. 



Argenti nitras is devoid of odour, has a disagreeable 

 metallic taste, is permanent in air, but blackens on exposure 

 to light or in contact with organic matters. It is soluble in 

 its own weight of cold water, ether, and glycerin, and slightly 

 soluble in rectified spirit. It blackens the cuticle, parts 

 readily with oxygen, and thus corrodes soft animal tissues. 



Like other silver salts, it is distinguished by giving, with 

 hydrochloric acid, a curdy-white precipitate of silver chloride 

 (AgCl), insoluble in nitric acid, but soluble in ammonia, and 

 darkened by exposure to light. 



ACTIONS AND USES. It is antiseptic, astringent, irritant, 

 and corrosive, is used as a caustic, and administered as an 

 astringent and nerve tonic. It induces emesis in animals 

 capable of vomiting. Large doses cause gastro-enteritis, 

 corrosion of the mucous membrane of the stomach and 

 intestine, and then prostration and collapse. 



Toxic EFFECTS. Like iron, zinc, and copper salts, which it 

 resembles, silver nitrate readily unites with albumin. It is 

 absorbed slowly as an albuminate ; and the astringent, 

 irritant, and caustic actions of the solid nitrate or a strong 

 solution, are confined to the parts with which it comes into 

 contact. When vomiting is prevented, 30 to 60 grains 



