And here we find another startling correspondence between the phenomena of wireless telegraphy and that of thought transference or transmission of mental vibrations. We allude to the fact that while a wireless telegraphic sending instrument may be sending forth vibrations of the strongest power, its messages are capable of being received or "picked up" only by those instruments which are "in tune" with the sending instrument to at least a certain degree; to all other instruments, those which are not "in tune" with the sending instrument, there is no message perceptible. Precisely this same state of affairs is found to prevail in the realm of mental vibrations and thought transmission. The individual receives only such messages as emanate from instruments with which he is "in tune"--to all the rest he is deaf and unconscious. But once "in tune" with the higher vibrations of the mental realm, he will receive every message traveling on that particular plane at that particular time, unless he deliberately shut them out. We shall see how this works out in ordinary life, when we consider the general subject of Telepathy and Thought Transference in the succeeding Chapter. In Tune With Higher Planes But, in connection with the above statement of the "in tune" law or rule of manifestation, we wish to call to the attention of the student the important fact that the same law prevails in the case of communications from the higher planes of existence--the so-called "spirit communications" and other messages of this kind reaching individuals on our own plane of existence. It is only when the individual on the "earth plane" becomes "in tune" with the sending mental instrument of the entity abiding on a higher plane of existence, that it is able to "pick up" the message being sent to earth. Even the same individual is often unable to "catch" the messages at one time, while at other times he experiences no difficulty whatsoever. An understanding of this fact--this law or rule of manifestation--will throw a great light over many dark places of misunderstanding and perplexity concerning certain phases of occult and psychic phenomena. This feature of such phenomena will be considered in detail in subsequent parts of this book. The Two Key-Words. Concluding our consideration of the "just how" of the transmission of thoughts, messages, and "psychograms" between two minds, be they both on earth plane, or one of the two on the higher planes, we would say: "Always remember the two Key-Words, namely TRANSFORMATION and ATTUNEMENT." These two Key-Words will enable you to unlock many doors of thought on these subjects--doors which otherwise will remain closed to you. PART III THOUGHT TRANSFERENCE