Sales promotion through your letter box is nothing new. 100 years ago it could come in the shape of an interesting post card for your collection. This card was sent from Coln, Germany, by a firm making Eau de Cologne, telling Mrs Hodding of St Albans than she can collect a sample from St Albans' major department store, J. Fisk & Son.
I have started to set up a page bringing together interesting examples of early advertising post cards. Have you any examples I could use?