USE OF POISONS FOR DESTROYING NOXIOUS MAMMALS. 425 



very slightly soluble in water alone, but if an acid be added it dis- 

 solves readily. It is soluble also in about six parts of chloroform. 

 The two salts named are freely soluble in 50 parts of cold water 

 and in two or three parts of boiling water. On account of its 

 solubility the sulphate is the most convenient for poisoning rodents, 

 and it should always be used in preference to the alkaloid. It is 

 usually slightly cheaper and is equally deadly. 



Strychnine is exceedingly bitter, and this bitterness is a partial 

 safeguard against the accidental sAvallowing of the poison. It acts 

 upon the nervous system of animals, producing tetanus, convulsions, 

 and speedy death. The least dose known to have been fatal to a 

 human being is half a grain, but a quarter of a grain is regarded as 

 a dangerous dose. The medicinal dose is one one-hundredth to one- 

 twentieth of a grain. 



The bitterness of strychnine sometimes causes baits to be rejected 

 by animals. To counteract this, sugar is generally used. The same 

 object is sometimes accomplished by mixing powdered strychnine 

 with honey or with its own weight of commercial saccharine. For 

 poisoning rabbits and field mice, which are accustomed to bitter foods, 

 no sweetening is required, and it is probable that the bitterness of 

 strychnine is no obstacle to poisoning certain other rodents. 



As a poison for noxious animals strychnine has several advantages 

 over the others commonly in use. It kills quickly, without the long 

 tortures of corrosive poisons. In spite of its bitterness, baits con- 

 taining it are rejected less often than those containing arsenic. If 

 strychnine is properly labeled and kept from children, it is less 

 dangerous to have on the premises than most other poisons. Should 

 strychnine be accidentally swallowed by an adult, antidotes are 

 usually available, and by prompt action a fatal result may be pre- 

 vented.*^ Finally, considering both cost and efficiency, strychnine is 

 an economical poison. 



Comparative cost of strychnine and arsenic. — The cheapness 

 of arsenic leads many to select it for poisoning noxious mammals. 

 But experiments by the Biological Survey show that strychnine, all 

 things considered, is a cheaper poison than arsenic. Strychnia sul- 

 phate may be purchased in bulk at about 75 cents an ounce; white 

 arsenic costs about 15 cents a pound. An ounce of strychnine will 



^ In case of poisoning by strychnine an emetic should be promptly given — a 

 teasi)oonful of mnstard in a glass of water (warm, if available). Another excel- 

 lent emetic is zinc sulphate (10 to 60 grains in tepid water) or apomorphine (4 

 drops by hypodermic injection). A stomach pump can not be used after the 

 first few minutes. As soon as the emetic has acted, the patient should be put 

 slightly under the influence of chloroform or ether, and kept so for several 

 hours. He should be kept in a darkened room and away from noise of all 

 kinds. Further treatment may be left to the physician, who should be sum- 

 moned as soon as the poisoning is discovered. 



