Extracted from Jacob Grimm's Teutonic Mythology
Water sprites have manythings in common with mountain sprites but many things peculiar to them.
The males like those of the schrat kind, come up singly rather than in companies, the water man is represented as oldish with a long beard, often he is many headed. In Danish folk song the enokke lifts his beard aloft he wears a green hat and when he grins you see his green teeth.
He at times is the figure of a wild boy with shaggy hair or else with yellow girls and a red cap
Nakki of the Finns is said to have iron teeth.
At times water sprites will go and buy grain and if they pay more than the price a dearth follows but if he buys cheaper the prices fall.
Dancing and song and music are the delight of all water sprites, like sirens the nixe by her song draws listing youth to herself then into the deep. In Sweden they tell of the stromkarls alluring enchanting strain they have eleven song variations but only ten may you dance to the eleventh belongs to the night spirit and his band; begin to t play that the table sand benches, cup and can, gray beards grandmothers, blind lame, and even babes in cradle would begin to dance.
The stromkarl loves to linger by mills and waterfulls hence his Norwegion name fossegrim people would offer a black lamb and were taught music by him in return the fossegrimm too on calm dark evenings entices men by his music and instruct in the fiddle or other stringed instruments in return for a little white he-goat. If the victim is fat the fossegrim clutches hold of the players right and guides it up and down till blood starts out of hall his finger tips, then the pupil is perfect in his art and can play so that all the trees shall dance and torrents in their fall stand still.
Although Christianity forbids such offerings people retain a certain awe and reverence and have not quite given up all faith in their power and influence.
The nix also extracts cruel sacrifices of which memory is preserved in nearly all popular tradition, when people are drowned in a river it is common to saw the river sprite demands his yearly victim which is usually an innocent child.
On the whole there runs through stories of water sprites a vein of cruilty of bloodthirstiness which is not found among the sprites of mountains woods and homes. The nix kills humans and his own folk who go ashore to mingle with men. A girl was taken by a sprite and passed fifteen years in a haf-fruns gard home (sea wife)and was never seen for all that time. Her brother rescued her
Some others suppose that they do not drown but instead bear peoples souls to their next abode
in seaden drowned men who's bodies ar enot found are supposed to have been drawn into the dwelling of hafafru