In this ad Listerine is positioned as a dandruff remedy! (I hope it's not the same formula I gargle with!)
Even though the ad is amusing today ... there's still things to be learned from it (from a copywriting perspective)
Take a look, here's the NO-OPT-IN link to this VERY retro Listerine ad from 1939.
Listerine Advertised as Dandruff Cure | Advertising Swipe File Example