1970 VW squareback wont start..
 

Just left work and I started it up and all of a sudden there was a deep humming sound. I started driving and then a really loud "loose chain" sound started from the rear.
Then my transmission started making alot of noise. And as i would drive the chain sound continued, as well as the humming.
I then finally got home shut it off and now it wont even start..
It just gives a really weak turn over sound and does nothing.

Please if you know anything about this let me know asap. I need this car to run!!
Thanks alot!!