MINEEAL OR INOEGANIC POISONS 63 



A full-grown sheep was not seriously affected by 20 

 grammes, but was killed by 60 grammes of the same salt. 



When given intravenously zinc sulphate acts rapidly ; 

 thus 30 grains depressed the heart's action, and killed a 

 dog in a few seconds (Christison). 



Symptoms. — Poisonous doses of zinc salts produce the 

 general symptoms of acute metal poisoning, and are not 

 marked in animals by remote effects. 



In the case of the calf above referred to, the administra- 

 tion of 100 grammes of zinc potassium chloride caused at once 

 blowing and distress, the animal lying down. After twenty- 

 four hours the temperature was 98° F., pulse 88 strong, faeces 

 watery, abdomen tucked up, back arched, and there were 

 rigors of fore and hind quarters. The symptoms passed 

 off slowly, the animal remaining; in an emaciated condition. 

 In sheep and pigs the irritant salts produce loss of 

 appetite, frothing, nausea, dulness, and general loss of con- 

 dition. 



Post-Mortem Appearances. — These are of acute gastro- 

 enteritis. A sheep poisoned by zinc potassium chloride 

 showed slight inflammation of the first and third stomachs, 

 but intense croupous inflammation, with fibrinous exudate, 

 of the fourth stomach. The whole of the alimentary 

 contents was very fluid and watery, and there was diffuse 

 but slight inflammation throughout the small and large 

 intestines and caecum. Kidneys and liver were normal, 

 and the bladder empty. The lungs were highly engorged. 

 Tpeatment. — Alkali carbonates tend to render the zinc 

 salts insoluble, and may be given as antidotes. Gastro- 

 enteritis is combated by demulcents. Vomitories or the 

 pump are used to' remove the cause. 



Chemical Diagnosis. — Zinc is separated from organic 

 matters in the systematic analysis by means of nitric acid. 

 Other metals having been removed or proved to be absent, 

 it is easily recognised by giving the colourless sulphide as 

 a precipitate when ammonium sulphide or sulphuretted 

 hydrogen is added to the ammoniacal solution. 



A delicate test consists in the precipitation of colourless 



