Rose has written a letter to her mum, which considering the tale she relates isn't very surprising. The Doctor had decided to take up stamp collecting; not the most exciting of past times recalls Rose, remembering a boy she went to Jericho Junior School with, Freddy or Frankie was his name. Anyway, Bath in 1840 is where the Doctor takes Rose to the printing place of the very first stamp – the Penny Black, the brain child of Rowland Hill who for the first time suggested a one price stamp for all any area in the country that the person sending the letter had to pay! (Up until then you paid to receive a letter and the cost depended on how far it had travelled).