178 



CIVIC BIOLOGY 



and not have the constant stream of rat and mouse immigra- 

 tion from surrounding homes. 



To work for days and finally out^Yit a wise old rat and 

 catch him often gives one a game and a story almost as instruc- 

 tive in animal cunning as that of old Lobo Rex Currumpa^. 

 Being chiefly nocturnal, and living, as they do, in the total 

 darkness of burrows and drains, rats sense danger mainly by 

 smell, and the smell of man, his archenemy, will scare a rat 

 away from a trap recently handled. But leave the trap, care- 

 fully covered with earth or bran or loft sweepings, in a natu- 

 ral runway or at the mouth of a burrow a week, the man 



scent disappears, the wisest 

 old rat has a moment of 

 absent-mindedness, and the 

 last one " puts his foot in it." 

 A study of rat traps is 

 mteresting, but is apt to 

 suo'orest that their manufac- 

 turers are chiefly concerned 

 with making something 

 which will not exterminate 

 their business by catching rats. xVll authorities to the con- 

 trary, notwithstanding, the writer, after ten years' active study 

 of the problem, would discard all rat traps which depend upon 

 being baited, except the cage or box traps to be described 

 below. Give him an old-fashioned steel spring trap, and, by 

 keeping it set year in and year out, he will guarantee, with the 

 aid of other methods to be described, to catch the last and the 

 first rat on any home premises. This does not apply to mouse 

 traps which require baitmg, and which, if kept baited and set 

 all the tvhile, insure catching the last and first mouse in any 

 house or barn. 



If the focal method described below cannot be adopted, a 

 French cage trap may prove of some use about a home, if it is 



Fig. 86. A durable and effective trap 



