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 ktfow. 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 this unseen wofld, the state into which maf> enters immediately after death—the Hades or under-^ world of the Greeks, the purgatory or intermediate state of Christianity, which was called by medkeval alchemists the astral plane. The object of this manual*is to collect and arrange the information with regard to this interesting region which is scattered through Theosophical literature, and also to supplement it slightly in cases where new facts have come to our knowledge. It must be understood.that any such additions are only the result of the investigations of a few explorers, and must not, therefore, be taken as in any way authoritative, but are given sffnply for what they are worth. On the other hand, every precaution in our power has been taken to ensure accuracy, ivr fact, old or