An illustrated treatise on the denizens of the invisible worlds and the individual s connection with them, including the 'Dweller on the Threshold,' elementals, natural principles, thought-forms, ghosts and specters. Modern authors who have specialized on the subject of the Nature Spirits include the Brothers Grimm, Thomas Keightley, and Dr. W. Y. Evans Wentz. In his remarkable volume 'The Fairy-Faith in the Celtic Countries,' Dr. Evans Wentz feels that authentic fairy tales are vestigial remains of a primitive religion which was diffused throughout the world at a remote time. Thomas Keightley points out that when we observe effects, we are inclined to search for causes, and to ascribe to such causes the attributes of intelligence. In early times our forefathers lived in close proximity to a natural world from which we are largely alienated. There were many mysteries which perturbed the unlettered and unschooled. It seemed to them that natural procedures were guided by some type of intelligence. There was a destiny that shaped the ends of things. There were rules which could not be broken, but no one knew why. The most obvious explanation was that all forms of life were intelligent, and it seemed reasonable to assume that their mental processes were similar to those of man. Even today we are inclined to view all forms of life as possessing a consciousness of some kind, and scientific research is supporting this point of view. Paracelsus probably received instruction from Near Eastern sages in Constantinople. He was also an avid reader of the scriptures, many sections of which he memorized, and for some years he was a Bible salesman. It was only natural that he would be especially intrigued by the philosophical aspects of the unseen world. This extended into the medical field and psychological therapy. His overall premise was that if humanity would keep faith with the orders of life, both visible and invisible, Nature and all its spirits would serve it well. The misuse of natural resources, visible or invisible, must end in disaster, and perversion ends in corruption. We have approached the problems of elementals and man fashioned elementaries according to concepts which have dominated human thinking for hundreds of years.