Though for the most part entirely unconscious of it, man passes the whole of his life in the midst of a vast and populous unseen world. During sleep or in trance, when the insistent physical senses are for the time in abeyance, this other world is to some extent open to him, and he will sometimes bring back from those conditions more or less vague memories of what he has seen and heard there. When, at the change which men call death, he lays aside his physical body altogether, it is into this unseen world that he passes, and in it he lives through the long centuries that intervene between his incarnations into this existence that we know. By far the greater part of these long periods is spent in the heaven-world, to which the sixth of these manuals is devoted; but what we have now to consider is the lower part of