274 ARSENICAL POISONING 



of appetite, no uneasiness or pain, and no alteration of the 

 pulse or respiration. 



Such comparatively negative effects are doubtless ex- 

 plained by the drug being given in insoluble form, and hence 

 being only partially and slowly absorbed. Much smaller 

 doses occasionally act with greater violence. Thus, according 

 to Gerlach, twenty grains cause acute diarrhoea ; and 

 Percivall mentions that two glandered horses, receiving five 

 grains daily in bolus, were attacked, one on the eighth, the 

 other on the ninth day, with shivering, loss of appetite, 

 nausea, purging, and other symptoms of abdominal irritation 

 and prostration of strength. One died, the other recovered. 

 These different effects depend partly on varying suscepti- 

 bility ; on the amount of food in the alimentary canal ; and 

 mainly on gradually acquired tolerance which enables 

 animals receiving arsenic regularly to take with impunity, 

 at one dose, as much as would kill a patient unused to the 

 drug. Large doses, moreover, produce inflammatory changes 

 in the lining of the alimentary canal which greatly retard 

 absorption. Arsenious anhydride is much more active in 

 solution than in substance. Thirty grains given daily, in 

 solution of potassium carbonate, destroyed a horse in four 

 days. Applied to wounds, Kaufmann states, it is much 

 more active than when swallowed. 



Baldwin reports the case of six horses poisoned by drinking 

 from a pail in which some arsenical sheep-dipping mixture 

 had been dissolved. Two died, and post-mortem examina- 

 tion revealed inflammation of the mucous coat of the 

 stomach, and patches of inflammation extending throughout 

 the intestines. The others suffered from dulness, colicky 

 pains, and purging ; the pulse was upwards of 70, and wiry ; 

 the extremities cold ; the visible mucous membranes highly 

 injected. One mare was ill for three or four days. The 

 treatment consisted of opiates and lime-water ( Veterinarian, 

 1858). 



Eleven cart horses were poisoned at Edgeware from drink- 

 ing water containing arsenic. They had been drawing heavy 

 loads of building materials fully eight miles from London, 

 were tired, and their stomachs empty, which doubtless 

 accounts for the rapid and serious results. Although 



