There is scarcely a current legend or superstition which cannot be traced to very remote sources. Thus, in the Chaldæo-Babylonian cosmogony there was a Triad which ruled the three zones of the universe: the heaven, by Anu; the surface of the earth and the atmosphere, by Bel; and the under-world, by Nonah. Now, Nonah is held to be both the same as the Assyrian Hea, or Saviour, and as the Noah of the Bible. So when Tiamat, the dragon, or leviathan, opens 'the fountains of the great deep,' and Anu, 'the windows of heaven,' it is Hea, or Noah, who saves the life of man.
This legend is supposed by M. François Lenormant to explain an allusion in one of the most ancient Accadian manuscripts in the British Museum to 'the serpent of seven heads, that beats the sea.' This Hydra was the type of the destructive water-demon who figures in the legends of all countries.
In the same way, to the Syrian fish deities, Dagon and Artergatis, must we look for the origin of our Undines and fish-maidens, and mermaidens.
The 'Nixy' of Germany has by some been supposed traceable to 'Old Nick'; but this is not probable, since St. Nicholas has been the patron-saint of sailors for many centuries. It was during the time of the Crusades that a vessel on the way to the Holy Land was in great peril, and St. Nicholas assuaged a tempest by his prayers. Since then he has been supposed to be the protector of mariners, even as Neptune was in ancient times; and in most Roman Catholic countries you will find in seaport towns churches dedicated to St. Nicholas, to which sailors resort to return thanks for preservation at sea, and to make votive offerings.
The German Nixy was, no doubt, a later form of the old Norse water-god Nikke. You meet with him again, in another form, in Neckan, the soulless, of whom Matthew Arnold sings:
'In summer on the headlands
The Baltic sea along
Sits Neckan with his harp of gold,
And sings his plaintive song.'
The 'Nixa' along the Baltic coast was once, however, much feared by the fishermen. It was the same spirit which appears as the Kelpie in Scotland—a water-demon which caused sudden floods to carry away the unwary, and then devoured them.
There was a river-goddess in Germany, whose temple stood at Magdeburg, of whom a legend exists that she also once visited earth and went to market in a Christian costume, where she was detected by a continual dripping of water from the corner of her apron. Generally speaking, however, the Nixies may be described as the descendants of the Naiads of ancient times, and as somewhat resembling the Russian Rusalkas, of which the peasantry live in much dread.
A Russian peasant, it is said, is so afraid of the water-spirits that he will not bathe without a cross round his neck, nor ford a stream on horseback without signing a cross on the water with a scythe or knife. In some parts these water-spirits are supposed to be the transformed souls of Pharaoh and his host, when they were drowned, and the number is always being increased by the souls of those who drown themselves.
It is said that 'in Bohemia' fishermen have been known to refuse aid to drowning persons lest 'Vodyany' would be offended and prevent the fish from entering the nets.