Yesterday's mechanical fly catcher inspired me to see what other devices inventors had created to rid ourselves of the pesky scourge. The idea, it turns out, is an old one.

Electro-mechanical fly catcher, by Everett Huckel Bickley, 1943

Everett Huckel Bickley (1888-1972), a Philadelphia-area inventor and entrepreneur, was responsible for dozens of inventions, some more marketable than others. His financial success came with the development of a bean-sorting machine that could, by use of photoelectric cell, sort good beans from bad. The sorter was the only invention from which Bickley ever made any considerable money, but it never dulled his enthusiasm for developing new ideas. At times he had up to nine active patent applications in the works, for such items as a nutcracker, a snow shovel, a slide mount, a faucet, and a photographic exposure meter.

Doodles, Drafts & Designs: Industrial Drawings from the Smithsonian

The diagram explains the workings:

1. Flies attracted by the bait light on cylinder.
2. Cylinder rotates carrying fly inside screen.
3. Fly eventually falls into kerosene and dies.

Doodles, Drafts & Designs: Industrial Drawings from the Smithsonian