restricted to actual impressions ;-ideas partake of this pleasurable excitement, and become so stimulated as not unfrequently to induce ecstatic illusions.

These are all the remarks which I have to offer on the causes that give rise to such a general state of mental excitement as is productive of spectral illusions; and it will be now advisable to take a short review of the conclusions at which we have arrived in some of the last chapters.

It was considered, that in every ecstacy, or state of general excitement of the mind, either pleasurable feelings were excited and painful ones depressed, or, vice versa, painful feelings were excited, and pleasurable ones depressed.

A cause, then, which, by stimulating organs of sensation, extends its vivifying influence to the renovated feelings of the mind, may modify an ecstacy in three

ways:

1st, It may impart a vivifying influence similar to that of any quality of feelings, pleasurable or painful, which is rendered intense, and may thus increase the force of the ecstacy.

2dly, It may impart a vivifying influence to any quality of feelings, pleasurable or painful, which is depressed; and by reducing this means, the intensity of the excited quality of feelings may shorten the duration of the ecstacy; or,

3dly, It may, if acutely and unremittingly prolonged, change the nature of its action, as from pleasure to pain, or from pain to pleasure, and thus, according to

the circumstances under which it acts, either increase the force of the general excitement, or shorten its duration.

To all these varieties of effects, however, which result from morbific causes of general excitement, there must evidently, from various idiosyncracies of constitution, arise frequent exceptions. For, among the numerous individuals who, about twenty years ago, imbibed the nitrous oxide, there were few whom it affected entirely alike. Indeed, to some persons, pain instead of pleasure resulted from the inhalation.*

I have at length concluded my observations on what may be considered as the leading mental laws which are connected with the origin of spectral impressions.

The general inference to be drawn from them is,— that APPARITIONS ARE NOTHING MORE THAN MORBID SYMPTOMS, WHICH ARE INDICATIVE OF AN INTENSE EXCITEMENT OF THE RENOVATED FEELINGS OF THE

MIND.

* One individual, after having imbibed the gas, experienced a pressure in all the muscles; a second, felt as if the bulk of the body was increased without its gravity; a third, as if a weight was pressing him to the ground; a fourth, complained of a pricking sensation in his stomach, but this soon gave way, and was succeeded by a lively delirium and laughter; a fifth, endured inexpressible uneasiness from a burning heat in the chest, and was afterwards thrown into a syncope of some minutes in duration.

PART V.

SLIGHT REMARKS ON THE MODIFICATIONS WHICH THE INTELLECTUAL FACULTY OFTEN UNDERGOES DURING INTENSE EXCITEMENTS OF THE MIND.