CHAPTER XVIII.

Same subject continued.

In proceeding with our analysis of the preceding argument, we shall observe, that the same view is confirmed by attending to the phenomena of sleep, and especially of its morbid states.

Sleep is not a state of absolute quiescence; of the negation, or even the suspension of action indeed, some organs appear to possess a greater degree of activity than usual, because, the intellectual function being less employed, a greater supply of nervous energy can be afforded without destroying the balance of constitutional power.

Thus is shown the unwearied action of the brain during sleep, inasmuch as it gives off such an amount of nervous energy as shall be sufficient to maintain the activity and integrity of those functions.

But many of its intellectual manifestations are absolutely laid aside; and hence it should seem, that, as an intellectual organ, it is more

liable to exhaustion than as a corporeal agent; and this is confirmed, day by day, by the greater fatigue, and the more rapid failure of power, which attaches to mental exertion, than to bodily labour.

Therefore, sleep seems to have been provided for the intellectual brain; and, in consequence of this state, it ceases to be the servant of the spiritual principle, and is no longer obedient to the will.

This repose of the brain is often incomplete; and then it continues a certain kind of action, without the guidance of the judgment, or the government of the will.

Whenever the brain is in a state of irritation, uiet sleep is impossible; and a state of morbid wakefulness is not unfrequently the result.

The brain may be roused to a state of excitation by various stimuli; and therefore i may be acted upon by different disturbing causes, with which we are at present unacquainted; because we know not the mode of relation subsisting between that viscus and its distant associated organs.

Thus, then, the brain is excited by various causes, producing corresponding varied effects, yet all agreeing in disturbing the manifestations of mind.

In reverie there is a continued action of the

brain, without the support of volition or the corrective influence of the judgment; and in this state unreal images are presented to the mind, with all the semblance of truth and reality. Under these circumstances, therefore, it is capable of producing images, imagining situations, and inventing consequences without reason or truth.

But if so, some other analogous, though unknown, process may be the result; and this unknown action may be the creation of spectral forms: at least, there is nothing irrational in this supposition.

This view is supported by the phenomena of nightmare, which are purely cerebral, and always disappear upon perfect wakening. It is most frequent and severe in that peculiar condition of the brain which has arisen from intellectual over-action,-namely, the irritability which is the consequence of specific exhaustion.

During this state, the distress of the patient is occasioned by his being placed in some. situation of danger, and by his inability to escape from it; and he awakes in violent agitation, with palpitation of the heart, and perspiration, which point out the really intense agony he has suffered from this visionary impression,

produced by a physical condition of the organ of mind.

Nightmare is generally preceded by unwonted drowsiness, aud brainular oppression, which enables those who are acquainted with its history, to predict its arrival.

Nightmare may be sometimes dependent upon the irritation of a distant organ: but where this is the case, still, it can only be accomplished through the intervention of the brain; for the patient must be asleep, or he does not suffer from the attack.

Any powerfully exciting cause applied to the brain late at night will almost unerringly bring on the attack in those who are so predisposed, and its intensity will be regulated by the greater or less morbid susceptibility of the cerebral organ, becoming aggravated in its maladies, and receding in its convalescence.

The illusions which accompany nightmare are so complete, that the patient verily believes in their actual existence; and it is only by the influence of the judgment, reason, and experience, that he can be disenchanted of their fallacious impression, or can be convinced of the contrary truth.

These illusions involve the appearance of different individuals; their speaking and acting

according to certain supposed circumstances, and all the consequences of such words and actions.

But if so, there is nothing unreasonable in supposing that similar illusions may attend other morbid conditions of the brain, during the continuance of which it is even more completely abstracted from the salutary influence of judgment, reason, and experience.

I proceed to the phenomena of dreaming.

There is great activity of the brain during sleep and this is not a consequence of the increased energy of the immaterial principle; because, if it were so, we should have to record perfect ideas, refined images, and correct notices, resulting from the agency of the spiritual principle disencumbered of its material shackles; instead of the common result, imperfect ideas, confused images, and incorrect impressions.

Here again, therefore, we trace dreaming to a peculiar action of the material brain, not of the immaterial principle.

The immaterial spirit is not necessarily engaged in the phenomena of dreaming: in sleep, the brain is not its servant, because, during that state, it is unfitted for intellectual operations. When it does act, it is without the