 After convincing Mary Jane Godwin , who had pursued them to Calais , that they did not wish to return , the trio travelled to Paris , and then , by donkey , mule , carriage , and foot , through a France recently ravaged by war , to Switzerland . " It was acting in a novel , being an incarnate romance , " Mary Shelley recalled in 1826 . As they travelled , Mary and Percy read works by Mary Wollstonecraft and others , kept a joint journal , and continued their own writing . At Lucerne , lack of money forced the three to turn back . They travelled down the Rhine and by land to the Dutch port of <unk> , arriving at Gravesend , Kent , on 13 September 1814 . 
