Grey Scale

Don't ever try to do a grey scale puzzle.  This one was bought by Pam when she stayed with us in October.  We worked on it then and I've just spent another 8 hours completing it.  Even at the end when I only had a few pieces left to put in I still had to guess (usually wrongly) where they should be.  Whole process not helped by 3 pieces being dropped on the floor and only two found initially!