The Fairy Mythology

We find in most countries a popular belief in different classes of beings distinct from men, and from the higher orders of divinities. These beings are usually believed to inhabit, in the caverns of earth, or the depths of the waters, a region of their own. They generally excel mankind in power and in knowledge, and like them are subject to the inevitable laws of death, though after a more prolonged period of existence.
How these classes were first called into existence it is not easy to say...