MINEEAL OE INOEGANIC POISONS 81 



by the alkaloid solanine contained in diseased potato. Nor 

 is the mechanism of salt poisoning well understood, for, 

 apart from the gastric disturbances naturally to be antici- 

 pated, there appear to be definite nervous effects. 



All concentrated solutions of salts when taken into the 

 stomach and intestines cause an increased inward flow of 

 water from the surrounding serum by reason of osmosis. 

 This may set up irritation and vomiting. There can be 

 no doubt that very large doses of many salts can produce 

 dangerous or even toxic effects, although the salt in question 

 has no specific action. 



Whilst, however, the question of salt poisoning demands 

 exact study, the actual records are sufficient to establish its 

 existence as a matter of practical fact. 



Brine poisoning is more obscure, since that fluid contains 

 other constituents than salt. Herring brine is held re- 

 sponsible for some cases of poisoning abroad. Besides 

 salt it contains nitre and the volatile toxic base tri- 

 methylamine. Since its toxicity, at first great, diminishes 

 with keeping, it is probable that bacterial action occurs 

 with production of toxic substances, and the nervous 

 symptoms are more marked in its action than with salt. 



Symptoms. — From the recorded instances the general 

 symptoms of salt poisoning in pigs^'^'^-''-^° involve loss of 

 appetite, thirst, champing and salivation ; in some instances 

 diarrhoea, and in others scanty, hard faeces ; the animals sit 

 like dogs on their hind legs, and then roll over on to their 

 sides ; there are vertigo and convulsive movements, dilata- 

 tion of the pupils, and blindness ; the convulsions increase 

 in frequency, and the subject loses power over the hind 

 quarters ; temperature normal, ears and skin cold ; death 

 takes place in convulsions. The onset of symptoms is 

 rapid, and death occurs within three days. 



Suffran ^ describes a case in which thirteen out of fifteen 

 fowls died after eating a salted potato mash — the symptoms 

 setting in within twelve hours. The birds fell from their 

 perches, showed signs ^ of great thirst and weakness, and 

 there was a viscous discharge from the beak. Experi- 



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