You can't blame the people of 1920 for falling for Edison's practical joke. After all, this was the man who invented the light bulb! When he told a magazine he'd invented a phone that communicates with spirits, hysteria understandably ensued.
Over 600 letters were sent in to American Magazine, which published Thomas Edison's quotes on this walky-talky with the deceased. Some of the questions readers asked were pretty mad - Gerald Fabris, who's the museum curator of sound recordings at the Thomas Edison National Historical Park, summarised the many responses into what you see below:
10. Too late! The ghosts are already working on the same machine.
9. This phone will kill us all! We need to believe in God and immortality!
8. Dead people have no memory, so how can you communicate with them?
7. How can I get one of these phones? Or, can I sell them when they hit stores?
6. How does the machine work?
5. Duh - you can't talk to spirits unless you use a human medium, silly.
4. Another "Communication With the Dead" machine? I already have one of those!
3. Beware, Mr. Edison! The spirits that would answer this phone are evil!
2. I am a medium. So call me if you need any help, Mr. Edison!
1. We whole-heartedly support this machine! (Of these, three letters appear to be from people formally educated in the field of science.)
Obviously Edison was either delusional or playing a prank on the world, considering not a single blueprint or prototype was ever found, OR MAYBE he's spent the years since his death in 1931 working on the phone. Any of you seen "Thomas Edison" flash up on your caller ID yet? [GEReports via Fark and Recombu]