In message , Sim D.
wrote


{*} contents would include the predictable items such as a selection
of that day's newspapers, written letters from each of the family,
brief history of the house and family, photographs videos CDs of music
and commentary from us all. A video of a trip round the town and some
of the local shops. Maps, both national and local. Most of this would
also be duplicated onto a computer hard disk drive which I understand
preserve their data pretty well,

Didn't you imply that you have learnt from the Blue Peter experience?
Will anyone be able to play a CD, video or access a hard disk in 100
years time? Isn't there already a problem with the physical longevity of
data on such media?
--
Alan