Expressions That Would Not Be Used or Understood Today

This thread reminds me of a hilarious video I watched once of teenagers being asked to make a call using a phone with a rotary dial. At first they didn’t know how to dial the number. Eventually they figured out how to do it, but they didn’t realise that they had to take the receiver off the cradle and listen for the dial tone before starting to dial. They were dialing first and THEN picking up the phone, and they couldn’t understand why it wasn’t working.