How do Cable Cars work?

[xaniac_uk]

I recently got back from a backpacking trip across the United States. My final destination was San Francisco which is famous for it's cable car system. I was just wandering how does this work? I've got an idea but I would like to know for sure.

[homer]

A cable car is pulled by an moving underground cable which sits between the rails and is gripped by a vice at the front of the car. The driver (gripman) operates a lever which grips the cable when the car is to move forward; when he wants to stop he releases the cable. In addition there are usually three braking mechanisms on top of the cable release - front wheel brakes, rear wheel brakes and track brakes.

[geofbob]

If you ever return, go to the Cable Car Barn on Mason Street where you can see the guts of the system working, with the cables of the various cable car routes being wound on giant wheels. There's a website - one of many on SF's cable cars - at http://www.sfcablecar.com/barn.html.