I think it right, therefore, to regard the quest of clairvoyance as a legitimate occupation, providing that it is purposeful and carried out with a right spirit, while not being allowed to interfere with the proper performance of one's ordinary duties in life. For it is possible to become over-zealous and even morbid over these mysteries of human life, and to become so obsessed by the idea of their importance as practically to render oneself unfitted for any ordinary pursuits, thereby producing an isolation that is in the best sense unprofitable. Moreover, there are mental dangers as well as spiritual and social to be feared, and it is unfortunately not uncommon to observe that neuraesthenia, nervous corrosion, and even insanity attends upon the tireless efforts of the enthusiast in this direction.
If we regard clairvoyance as a normal faculty we are more likely to treat it normally than if we give it a paramount and exceptional value and seek to beatify those in whom it appears. I am convinced from experience that it is both normal and educable though not usually active in the large majority of people. I am also of the opinion that it is not peculiar, except in its higher functions, to human beings. I have known animals to possess this faculty; in a higher degree I have seen humans in the exercise of it. Perhaps even the archangels are yet seeking their vision of God.
But to us as normal beings clairvoyance should appear a potentially normal faculty, to be studied and pursued by methods that are efficient while yet harmless; and this is the purport of the present treatise. I will therefore ask the reader to follow me in these pages with a mind divested of all disposition to the supernatural.
The first consideration by those who would develop clairvoyance by artificial aids is the choice of a suitable agent. It has been the practice for many years to substitute the original beryl or "rock crystal" by a glass ball. I admit that many specimens I have seen are very creditable productions, but they are nevertheless quite worthless from the point of view of those who consider material agents to be important factors in the production of clairvoyance. The glass ball may, however, very well serve the preliminary essential of concentration, and, if the faculty of clairvoyance is at all active, will be entirely effective as an agent.
