The bottle opener alarm, scanned from the December 1919 issue of Electrical Experimenter magazine (Novak Archive)
Are you a soda fountain owner? Did you just time travel from America, circa 1919? Then have I got an invention for you!
Electrical Experimenter magazine was all the rage for tech nerds of the 1910s. And after the end of World War I, during which the magazine focused heavily on the war, the magazine was allowed to get back into more silly DIY projects -- like this clever bottle opener alarm.
The article that accompanied this image told readers about the "thousands of owners of small soda water stands all over the country" who were tragically losing "hundreds of dollars due to people helping themselves" whenever the owner of the store wasn't looking.
The solution to all this no-good thievery? An invention by Charles F. Scarborough, which alerted everyone around that a soda pop heist was in progress. Why just soda pop? Alcohol prohibition was in its early stages and would become the law in every state by the following year.
From the December 1919 issue of Electrical Experimenter:
The alarm apparatus comprises a dry cell battery and bell mounted in small box, which can be placed out of sight so far as the customers are concerned. A flexible duplex wire or cable leads from the alarm box to the bottle-cap removing device. This cap remover comprises two distinct and thoroly [sic] insulated metallic rings which are connected to the bell circuit. If the circuit is closed as would be caused by a piece of metal coming in contact with the two metal fingers of the cap remover, then it will sound the alarm.
Such soda bottles are usually opened up by a regular cap-remover and to make sure that the person desirous of stealing a drink, will use the electrified bottle opener, this is placed in as conspicuous a position as possible as the illustration shows. He grabs the cap remover, and the minute that it is placed in contact with the metal cap of the bottle, the circuit is closed -- the bell rings, thus notifying the proprietor that he has "customers."
It's kind of bizarre to think that securing the bottle opener rather than the bottles was how to prevent theft. But obviously that was seen as an ingenious way to do it. People weren't carrying around bottle openers on their keychains back in 1919, like college kids (and your dirtbag cousin Eric) might today.