Slip sliding away.

http://youtu.be/5_H-LY4Jb2M

After taking our Xmas tree to the recycling facilities, I spotted that one of the tyres on my taxi was low. Saw there was a screw embedded in it.
So after leaving at at my local garage, I walked back home over the railway line. This was the scene that greeted me. Ice. Solid ice.
On returning to pick up my car, it was revealed that there was also a nail keeping the screw company in the tyre.