On the reverse of most of the materials there are three reference numbers, which reveal how the counties have been organised over time. There are two older reference numbers written in pen – sometimes blue, sometimes pink, sometimes red – and the most recent reference numbers written in pencil by Dr Juliet Bailey during her recent re-cataloguing of the collection. These can be seen on the reverse of the print showing Heveringham Hall, Suffolk below. It is evident from the way that the older and newer reference numbers do not always align that some of the items in the collection may have gone missing. For instance, there are currently twenty-two items in the Cambridgeshire folder, but one of the old referencing systems indicates that there might have been twenty-seven. Similarly, Devon has seventy-three items now, but an older referencing system suggests that previously there were over eighty.
During the digitisation process, if an item was found to be in the wrong county (or the wrong Riding in the case of Yorkshire), then it was not given a new reference number for its correct location. This was done to preserve the organisation and order of the collection as much as possible. To account for this, the correct location is always given in the ‘Location’ field while retaining the original reference number, so that when any given place is searched all relevant items will present themselves. Take, for example, High Wycombe, which was previously assigned to the county of Berkshire when it is in fact in Buckinghamshire. It retains the original reference number of BERKS-015 but its Location has been updated to say that it is in Buckinghamshire. Additionally, please note that all placenames and building names have been modernised to make them easier to find.