The most elementary and simple form in which mental vibrations are
transmitted is that which may be called Thought Transference. In the
category of Thought Transference may be included two quite general
classes, as follows: (1) Involuntary Transmission of Mental Vibrations,
and (2) Voluntary Transmission of Mental Vibrations, commonly known as
Telepathy. In this part of this book both of these general classes of
Thought Transference shall be considered in some detail.