Anti-pest Doorbell Discourages Agents and Bill Collectors 
I found the quaint reference to "the housewife" amusing... I wonder how old the ad is? It's a good idea. Except if nobody is home!
http://blog.modernmechanix.com/mags/qf/c/ModernMechanix/3-1934/lrg_anti_pest_door.jpg

I found the quaint reference to "the housewife" amusing... I wonder how old the ad is? It's a good idea. Except if nobody is home!
http://blog.modernmechanix.com/mags/qf/c/ModernMechanix/3-1934/lrg_anti_pest_door.jpg