Chris Stann wrote:
>
> >You don't want to do this, believe me: If, perchance, you lock up the
> >rear wheels, the vehicle will spin around.

Saw a physics demonstration by Earl Zwicker at the Illinois Institute of
Technology. He used a model car on a board and locked up just the rear
wheels.  When he lifted one end of the board far enough to make the car
move, sure enough, it swapped ends.
  I was a little surprised to see this, and it cured my urge to grab
that emergency brake on ice or snow.

Larry A.
no snow yet in Chicago