Aha! I got your attention there! 🙂 That title was the tagline used in order to sell their company’s wonder product back in the early twentieth century.
I got this very old scanned magazine page from “The Silent Worker” Issue No. 33 printed in 1920 by then Gallaudet College. The device called “Acousticon” was invented and sold by Dictograph Products Corporation of New York City. It’s like a portable hearing aid with microphone system together with six step volume control which can be carried in a suitcase. Wow! I couldn’t imagine deaf people wearing that gadget while walking on the street in those days.
The scanned article was reprinted by the Aladin WLRC Catalog Libraries. They have a huge repository of old magazines kept by large universities in the US. Their site is a great resource for most of your researches and studies. Enjoy 🙂