There are a number of points which can be used to back up the "we can't
offer permenant display" statement:

    If our building is damaged (by hurricane, earthquake, bomb etc.) we
may have to close to the public for a period of refurbishment.

    Less dramatically, galleries need periodic redecoration.

    The object itself will need to be conserved from time to time (even
if its kept in the best of all possible display conditions).

    We have a large collection which is in store, over a period of time
we try to ensure that as much of possible is shown to the public, in
order to do this we must rotate the objects on display.

    Even when an object is not on "display" we will endevour to allow
access for research purposes and for those who have an especial desire
to see it.

    For sensitive items (such as textiles & watercolours):  Displaying
for short periods of time (e.g. three months every two or three years)
will mean that it will survive for much longer and be seen by more
generations.


Usually, given a reasonable argument, most donors that I've dealt with
will drop the more impossible of their conditions.  From my point of
view any conditions are a problem (even if they are not unreasonable)
because they mean that the object requires separate handling and more
involved documentation.

Trevor Reynolds
Collections Registrar
English Heritage
--
Trevor Reynolds