Rim Blow horn
There are two thin pieces of cooper that run around your steering wheel, when you squeeze the inner rubber that will press the two pieces of cooper together and cause the horn to honk. That rubber piece gets brittle over time and can cause problems as well as the copper being pretty thin. I am currently having the same problem with mine.
My brother took his to the Mopar Nats and gave it to a guy who restores Rim Blows
http://www.rimblowsteeringwheels.com/. He seems to do real good work and i am planning on sending mine after my brother gets his back so i can check out his work.