urd one, and the reason the dreamer notices it only on
awaking is that he is absent from the visible body during sleep.

The proof of the departure of the astral body during sleep has been
ascertained by a certain number of seers, but the absurdity of the
commonplace dream is a rational proof thereof, one which must here be
mentioned. As another rational proof of the existence of a second
vehicle of consciousness, we must also notice the regular registering
of the commonplace dream, because it takes place in the brain, and the
habitual non-registering of the true dream experience, because this
latter takes place in the externalised astral body.

Why does the astral body leave the physical during sleep? This
question is beyond our power to answer, though a few considerations on
this point may be advanced.

Sleep is characterised by the transfer of consciousness from the
physical to the astral body; this transfer seems to take place
normally under the influence of bodily fatigue. After the day's
activity, the senses no longer afford keen sensations, and as it is
the energy of these sensations that keeps the consciousness "centred"
in the brain[5]; this consciousness, when the senses are lulled to
sleep, centres in the finer body, which then leaves the physical body
with a slight shock.

It is, however, of the real dream--which is at times so intelligent
that it has been called lucid, and at all events is reasonable,
logical, and co-ordinate--that we wish to speak. In most cases this
dream consists of a series of thoughts due to the soul in action in
the astral body; it is sometimes the result of seeing mental pictures
of the future[6] or else it represents quite another form of animistic
activity, as circumstances and the degree of the dreamer's development
permit.

It is in the lucid dream--whether belonging to normal or to abnormal
sleep--that occur those numerous and well-known cases of visions past
or future to be found in so many of the books dealing with this
special subject.

To these same states of higher consciousness are due such productions
as Walter Scott's _Ivanhoe_. The author, suffering from fever, wrote
this work whilst in a kind of delirious condition; _Ivanhoe_ was
printed before the recovery of the author, who, on reading it at a
later date, had not the slightest recollection that it was his own
production. (Ribot's _Maladies de la Memoire_, p. 41.)

Walter Scott remembered nothing, because _Iv