I remember having a very similar looking phone book growing up, but without the gigantic, high tech automatic dialer attached to it. What gigantic dialer? Click through to see what I'm talking about.
To make a call, you would slide the lever on the directory down to the line of the handwritten name of your 'speed dial' contact. The auto dialer does the rest by moving a brass disk that represents that number into the phone circuit....which eventually dials the number. I just suddenly gained huge respect for the speed dial on my mobile phone.
-via Boing Boing