On 10/6/06, David Gerard dgerard@gmail.com wrote:
Someone got a letter from OS saying which 50-year period it was, didn't they? Clearly and unambiguously. I know we're clear 50 years after *publication*. I suppose it depends what counts as "publication."
I doubt there is much in the way of OS maps that have not been published. The photography stuff is different. Some stuff may have surfaced in archiology journals but it is the case that much has not been published (a lot is still film fortunetly I think they had stoped using Nitrocellulose by that point).