Sylphs in the fantastic system of the Paracelsists, are the elemental spirits of the air, who, like the other elemental spirits, hold an intermediate place between immaterial and material beings. They eat, drink, speak, move about, beget children, and are subject to infirmities like men; but, on the other hand, they resemble spirits in being more nimble and swift in their motions, while their bodies are more diaphanous than those of the human race. They also surpass the latter in their knowledge both of the present and the future, but have no soul; and when they die, nothing is left. In form they are ruder, taller, and stronger than men; but stand nearest to them of all the elemental spirits, and as a consequence hold intercourse with human creatures. When they have children by marriage with mortals, the children have souls, and belong to the human race. Originally masculine, they have come, probably by the etherealization of poets, to be considered as feminine.