In Bram Stoker's Dracula Dr. Abraham Van Helsing the vampire authority, suggested that vampires could transform into a mist, although their ability to travel very far in this form was quite limited. Dracula adopted this form to conceal himself on the ship Demeter while traveling to England. In this form, he could move with ease in and out of the box in which he rested. Van Helsing, acknowledging this ability, sealed the door of the vault of the vampirized Lucy Westenra's resting place with a putty containing flakes of a eucharistic wafer so not the tiniest space was left for her to escape. He later sealed the door to Castle Dracula in a similar manner.
Dracula's primary appearances in the form of mist were during his attacks on Mina Murray In Murray's record of the first attack, she noted that she saw a thin streak of white mist that moved across the lawn. It seemed to have a sentience and vitality all its own. The mist started to move into the room, not through the window, but through the joinings of the door. The mist concentrated into a cloud out of which Dracula emerged. Several days later, when the men finally figured out that Murray was under attack, they went to her room and found her drinking Dracula's blood. They moved toward him with crucifixes in hand, but he turned back into mist and disappeared under the door.
The idea of the vampire transforming into mist was a minor concept in folklore, but it was occasionally mentioned as a logical means for the vampire to leave and return from the grave without disturbing the topsoil that covered the coffin. The idea of such a transformation was often made when small holes apparently leading downward to the coffin lid appeared on the top of the grave.