POISONS AND POISONING. 57 



poison by emptying the digestive tract, so far as may be, with a non- 

 irritating purge. Castor oil in doses of 1 pint to 2 quarts is best 

 adapted to this pui^pose. If the poison is known to be nonirritant — 

 as a narcotic plant — from 10 to 20 drops of croton oil may be given 

 with a quart of castor oil. To protect the mucous membrane from 

 the action of strong irritants one may give flaxseed tea. barley water, 

 the whites of eggs, milk, butter, olive oil. or fresh lard. Chemical 

 antidotes may sometimes be used for special poisons, as advised 

 below. In general, if an acid has been taken it may be neutralized 

 with an alkali, such as chalk, magnesia, bicarbonate of soda (baking 

 soda), ammonia (diluted), or soap. If the poison is an alkali, such 

 as caustic soda or i»tash (lye), or ammonia, an acid, such as diluted 

 (1 per cent) sulphuric acid or vinegar, may be administered. Special 

 treatments and antidotes are considered below. 



A poisonous agent may be so gradually introduced into the system 

 as to slowly develop the power of resistance against its own action. 

 In other cases, where the poison is introduced slowly, the poisonous 

 action becomes cumulative, and although there is no increase in the 

 quantity taken, violent symptoms are suddenly developed, as if the 

 whole amount, the consumption of which may have extended over a 

 considerable period, had been given in one dose. Other agents, 

 poisonous in their nature, tend to deteriorate some of the important 

 organs and. interfering with their natural functions, are productive 

 of conditions of ill health which, although not necessarily fatal, are 

 important. Such a class might properly be called chronic ]ioisons. 

 Poisons of themselves dangerous when administered in large doses 

 are used medicinally for curative purposes, and a very large percent- 

 age of the pharmaceutical preparations used in the practice of medi- 

 cine if given in excessive quantities might produce serious results. 

 In the administration of medicines, therefore, care should be exer- 

 cised not only that the animal is not poisoned by the administration 

 of an excessive dose, but that injury is not done by continued treat- 

 ment with medicines the administration of which is not called for. 



MINERAL POISONS. 

 ARSKNIC POISONING. 



Of the common irritant and corrosive poisons, arsenic, especially 

 one of its compounds (Paris green, Scheel's green, or cobalt) . is likely 

 to be the most dangerous to our class of patients. The common prac- 

 tice of using Paris green as an insecticide for the destruction of potato 

 beetle and other insect enemies of the farmer and fruit grower has 

 had the effect of introducing it into almost all farming establish- 

 ments. White arsenic is also a principal ingredient in many of the 

 popular sheep-dipping preparations, and poisoning from this source 



