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CIVIC BIOLOGY 



last old wise ones. Above all, use clean scalded dishes and 

 utensils and avoid all possible taint of man-smell on the bait. 

 Arsenic is one of the most common ingredients of rat poisons 

 and has the advantage also of being tasteless and of causing 

 intense thirst so that the animals leave the premises in search 

 of water. It may be used in combination with any of the baits 

 described above. In mixing with corn or oatmeal take one 

 twelfth by weight of the poison. In putting the above poisons 

 in houses or barns be sure to have no water accessible inside 

 the buildings ; but leave doors and windows open, and, if a 

 pan of water is sunk in the ground in the yard, rats and mice 



Bait 



FIG. 88. The poison box 



The inner box, where the bait is put, should be about 4-6 inches smaller in hori- 

 zontal dimensions. The strip a, \ X 1 inch, is nailed all around the bottom of the 

 larger box to prevent scattering of poisoned material. Bait with pieces too large 

 to be carried out. Leave holes in lower corners small for rats to enlarge 



in numbers may be seen dying and dead around it. They even 

 lose all fear of man and crawl to the water to drink in broad 

 daylight, and commonly remain at the water until they die. 



To destroy rats on farms. Each evening when the cows are milked 

 place a little fresh milk in a shallow pan w r here the rats can get it. 

 Continue this for a week or more until the rats get bold and impatient 

 to get at it. Then mix arsenic with the milk and await results. This 

 plan is said to entirely clean a barn of rats. Quoted by Lantz from 

 E. H. Reihl, in Cohnan's Rural World, January 29, 1908 



Strychnine acts so quickly that there is danger, when used 

 about buildings, that the animals may die in the walls. In 



