Hall Place in West Meon, Hampshire, is currently the home of Michael and Claudia Langdon. Yet for many years it was owned by the grandparents of HRH The Duchess of Cornwall. The house, so well known to The Duchess in her childhood, was specially chosen by her for coverage in her guest-edited issue of Country Life. It is revealed in a new light by fresh documentary research, as John Goodall reports. Photographs by Paul Highnam for Country Life.