216 DISEASES OF THE DIGESTIVE APPARATUS. 



The principal effects of the nitrates of potash and of soda are 

 due to the nitric acid element ; but potassium nitrate acts more 

 quickly than sodium nitrate on account of the potassium element. 

 (Fatal dose of nitrate of potassium in the dog, 0.02 per kilogramme 

 of body-weight; that of nitrate of soda in the rabbit, per kilo- 

 gramme of body-weight, is 3.9 grammes.) 



The toxic property of Chilean nitrate is not at all due to im- 

 purities that it may contain. Pure nitrate of soda is prone to act 

 more violently than impure nitrate employed as a chemical agent in 

 composts (Frohner). It has been advanced that these two salt& 

 introduced iuto the organism are reduced to nitrites, and that the 

 oxygen becomes free and exerts a toxic action upon the blood ; but 

 the accuracy of this theory is not yet demonstrated. 



The intensity of the effects of these agents is in inverse ratio to 

 the fulness of the stomach. 



6. Poisoning by Tartar Emetic. 



Symptoms. Ulcerated stomatitis, salivation, vomitings, colics, 

 diarrhea ; vertigo, trembling, spasms, paralysis ; small, hard, often 

 imperceptible pulse ; accelerated respiration ; pneumonia. Rapid 

 death. 



Pathological anatomy. There is an inflammation and cauteri- 

 zation of the mucous membrane throughout the entire length of the 

 digestive canal, and mainly in the stomach ; pulmonary hyperemia, 

 desquamation of the epithelium of the bronchial tubes, hemorrhagic 

 infarct, pneumonia. 



Treatment. Tannin (decoction of oak-bark, ink) ; also oils, 

 mucilages, narcotic substances, etc. ; ice pills for the dog. 



Poisonings from tartar emetic are sometimes caused by the ad- 

 ministration of an excessive dose of this agent, at other times by its 

 too great concentration. It ought to be a rule not to give tartar 

 emetic except in a very weak solution. The toxic action of this 

 drug is partly due to the potassium (paralysis of the heart), as well 

 as to antimony (fatty infiltration of the organs). Its principal 

 antidote is tannin, which, with the oxide of antimony, forms an in- 

 soluble compound. Fatal dose for horse and ox, 25 to 30 grammes; 

 for the pig, 6 to 8 grammes ; for the dog and cat (except when 

 there is vomiting), 0.2 to 0.5 gramme. 



