Bernie B Have you ever taken a trip in a railway carriage at about 100 km/h? If not, then no doubt you have been in a moving vehicle of some description at some time in your life and are possessed of some ability to imagine the railway carriage journey described. If you were in such a carriage, seated in the middle of the carriage facing the rear of the train and travelling at 100 k/mh, if you were to throw a ball into the air -- say half-way to the ceiling -- with the intention of catching it when it descends, would you succeed, or are you of the opinion that the ball would fly to the rear end of the carriage to bounce off the rear end wall? Points will be awarded if you append your reasoning. Paul D ____________________________________________________________________________________ Yahoo!7 Mail has just got even bigger and better with unlimited storage on all webmail accounts. http://au.docs.yahoo.com/mail/unlimitedstorage.html