5 



sugar sirup and stir thoroughly. A smaller quantity of the poison may 

 be prepared with a proportional quantity of water. In preparing 

 the bait it is necessary that all the oatmeal should be moistened with 

 sirup. Wheat is the most convenient alternative bait. It should be 

 soaked over night in the strychnine sirup. 



Other Poisons. — The two poisons most commonly used for rats and 

 mice are arsenic and phosphorus, nearly all commercial preparations 

 containing one or the other as a basis. While experiments prove that 

 rats have great powers of resistance to arsenic, it may sometimes be 

 used advantageously as an alternative poison. Preparations of phos- 

 phorus sold by druggists are often too weak to be effective; and 

 home-made mixtures, when of sufficient strength, are dangerous, as 

 rats may carry the baits into walls or crannies and thus cause fires. 

 For these and other reasons the Biological Survey does not recom- 

 mend preparations containing phosphorus. 



Poison in the Poultry House. — For poisoning rats in buildings and 

 yards occupied by poultry, the following method is recommended: 

 Two wooden boxes should be used, one considerably larger than the 

 other, and each having two or more holes in the sides large enough 

 to admit rats. The poisoned bait should be placed on the bottom 

 and near the middle of the larger box, and the smaller box should 

 then be inverted over it. Rats thus have free access to the bait, but 

 fowls are excluded. 



TRAPPING. 



Trapping, if persistently followed, is one of the most effective 

 methods of destroying rats. The improved modern traps with a 

 wire fall released b}^ a baited trigger and driven by a coiled spring 

 have marked advantages over the old forms, and many of them may 

 be used at the same time. These traps, sometimes called guillotine 

 traps, are of many designs, but the more simply constructed are to be 

 preferred. Probably those made entirely of metal are the best, as 

 they are less likely to absorb and retain odors. 



In illustration of the effectiveness of traps, it may be related that 

 a year or two ago a large department store in Washington expe- 

 rienced heavy losses of gloves, lace curtains, and other merchandise 

 from rat depredations. For several months the damages amounted 

 to from $10 to $30 nightly. After many unsuccessful attempts to 

 abate the nuisance the managers were advised to try the improved 

 traps. As a result 136 rats were killed during the first twenty 

 nights, when the losses practically ceased, and the method ha.s been 

 continued in the store ever since with satisfactory results. 



Guillotine traps should be baited with small pieces of Vienna 

 sausage (Wienerwurst) or bacon. The trigger wire should be bent 



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