IRON IODIDE 259 



As a tonic for horses and cattle, one to two drachms iron 

 sulphate, and half an ounce each of gentian and ginger, are 

 made into bolus, or dissolved in a pint of ale or gruel. Such 

 proportions make three or four doses for sheep and eight or 

 ten for dogs. Preparations of iron intended to act as tonics 

 should be given during or shortly after meals. Full doses 

 introduced into the empty stomach, especially of dogs, are 

 apt to cause dyspepsia. To obviate gastric irritation or 

 constipation, and maintain the continued good effects of 

 iron tonics, after being used for a week or ten days they 

 should for several days be withheld, or replaced by other 

 tonics. Constipation and the dark colour and fcetor com- 

 municated to the dejections are abated by appropriate diet, 

 combination with Epsom or Glauber salt, or by an occasional 

 laxative. 



IRON IODIDE. Ferri lodidum. FeI 2 4Aq. (Not official.) 



When iodine, iron wire, and distilled water are gradually 

 heated together, combination occurs, and the solution, 

 filtered and evaporated, yields tabular green crystals, which 

 are inodorous, have a styptic, metallic taste, and are soluble 

 in about their own weight of water and alcohol. When 

 heated, iron iodide gives off violet-coloured fumes of iodine, 

 and, exposed to the air, it deliquesces and acquires a red- 

 brown colour. This oxidation is retarded by keeping the 

 solution in contact with fresh iron wire, in well-stoppered 

 bottles, secluded from light, or by boiling the freshly- 

 prepared solution in syrup. 



ACTIONS, USES, AND DOSES. It is a haematinic, altera- 

 tive, and astringent. Poisonous doses are irritant, and pro- 

 duce the effects of iron rather than of iodine. Thus Cogs- 

 well found that three drachms caused in dogs vomiting and 

 purging, while one drachm in concentrated solution killed a 

 rabbit in three hours and a half, with the symptoms and 

 post-mortem appearances of poisoning with other soluble 

 salts of iron. 



Besides being used for the same haematinic purposes as the 

 sulphate, it is given .to promote absorption of glandular en- 

 largements, especially in young and weakly animals : it is 



