OK. I got one.

You know those corrigated cardboard boxes that you can buy flat packed from office suppliers and fold up yourself? Once you've folded them up, they have a temporary property of volume. It would have to be a temporary property because before it was folded, it would not be a volume holding object and to give it a volume property would be non-sensible. The volume property lasts for as long as the box is complete as a box and becomes obselete when the box is then flat packed again. When the box isn't folded it is still the same object, but it has no volume property.

Sharon