Phones

We were talking about Darius I from the Persian Empire in history.  He was credited with creating the first mail system to communicate with the 20 provinces within his kingdom.  He spent a lot of time improving roads so the messages could make it to their destination more quickly.  I said that he needed to do that because they couldn't just pick up their cell phones and talk to each other and they didn't have home phones either.  Kate said, "What's a home phone?"  I said, "You know, the phones that hang on walls in a house."  Kate says, "Oh yeah, I think I remember those!"