THE GROUND SQUIRRELS OF CALIFORNIA. 



783 



Antidote — For a human being, give an emetic, such as mustard in doses of 2 to 4 

 teaspoonfuls in a cupful of tepid water, or, better, copper sulphate in doses of 

 3 to 5 grains in one-half cup of water until vomiting is started. Do not give oils 

 or fats. Administer 2 or 3 tablespoonfuls of hydrogen peroxide (dioxygen) to 

 the empty stomach followed by a saline cathartic. Do not give milk under any 

 circumstances. 



ARSENIC. 



Effect — It is both local and remote in action. It irritates the digestive tract and 



produces nephritis. It also slightly resembles phosphorus in its late effects. 

 Fatal Dose — For a human being, about 1.5 to 3 grains at least. 

 Advantages — ■ 



1. Inexpensive. 



2. Easy to obtain, but its usefulness as a rodent poison has not been fully 



determined nor methods of application placed on a practical basis. 

 Objections — 



1. Acid in reaction, therefore, causes souring of baits and the metallic taste is 



objectionable to rodents. 



2. Uncertain in action. 



3. Taken in large doses usually causes animals to vomit and recover. 



4. In small doses develops an immunity. 



Antidote — Give an emetic, followed by large draughts of milk. 



POTASSIUM CYANIDE. 



Effect — In some cases it may be slightly local in action but it is always remote. It 

 acts very quickly, causing paralysis of the nerve centers, with cessation of 

 respiration. 



Fatal Dose — About 2.5 to 5 grains is generally accepted as the minimum required 

 for man. 



Advantages — 



1. Inexpensive. 



2. Acts quickly. 

 Objections — 



1. It will not stand exposure. The effective part of the chemical compound soon 



escapes as a gas into the air. 



2. When taken in doses that are too strong, the animal will often vomit and 



recover. 



3. Dangerous to have about. 



Antidote — Must be given quickly. Give strong emetic until vomiting is started. As 

 this poison affects respiration and heart action, artificial respiration must be 

 applied. 



STRYCHNINE. 



Effect — It is absorbed readily and carried to the spinal cord, producing clonic or 



tetanic convulsions, or both. Death occurs from paralysis. 

 Fatal Dose — One grain is about the fatal dose to a human being. 

 Advantages — 



1. Certainty in action. 



2. Antidotes simple and easy to obtain in case of accidental poisoning. 



3. Small amount fatal to rodents. A much larger amount in proportion to weight 



required to be fatal to most game birds. Quail, grouse, and almost all 

 gallinaceous birds are practically immune. 



4. Its bitterness acts somewhat as a safeguard to accidental swallowing. 



5. It is more economical than other poisons when results are taken into con- 



sideration. 



191 



