Windshield wiper woes...

So,

I was on my way home from work last night and the bottom dropped out (Like it tends to do here in SC in the summer). Turned my wipers on low and they worked for a few minutes. Then they just stopped.. dead in the middle of my windshield. :wack:

The vehicle in question is a '73 swinger with the 3 position switch. When I turn them on I can still here the motor in all 3 speeds, just no movement.

This is my first A body, and Mopar for that matter, so do you guys have any advice?

I do have the service manual for my car, but I'm working nights this week and stuck here.

Any advice would be greatly appreciated!!!