ful images, which have had their origin in various popular superstitions. Our attention will now become exclusively confined to the different subordinate incidents, which are reported to have taken place during communications held with apparitions. We shall find, that the quality and form of these unearthly visitants, their strange errands to the earth, and their seemingly capricious conduct, are not the indications of a proper world of spirits, as pneumatologists have averred, but that they merely prove the operation of certain laws of the mind, modified by the influence of those morbific causes, which are capable of imparting an undue vividness to thought. But, in pursuing this investigation, I shall often have occasion to lament that many valuable facts, which intense excitements of the mind are calculated to develop, should have been, on the one hand, distorted by superstition,* or, on the other hand, totally concealed from the world for fear of ridicule. But Nicolai's interesting detail of his own case first shewed in what light spectral impressions ought to be considered: nor can I conclude this department of my researches more appropriately, than by holding out, as a memorable example, the motives by which he was induced to examine the mental phenomena under which he laboured, and to present them to the world with an accuracy, that must ever recommend his narrative to the attentive consideration of the physiologist and of the metaphysician. His words are as follows: *See Note 5. "Had I not been able to distinguish phantasms from phenomena, I must have been insane. Had I been fanatic or superstitious, I should have been terrified at my own phantasms, and probably might have been seized with some alarming disorder. Had I been attached to the marvellous, I should have sought to magnify my own importance, by asserting that I had seen spirits; and who could have disputed the facts with me? The year 1791 would perhaps have been the time to have given importance to these apparitions. In this case, however, the advantage of sound philosophy and deliberate observation may be seen. Both prevented me from becoming either a lunatic or an enthusiast; for with nerves so strongly excited, and blood so quick in circulation, either misfortune might have easily befallen me. But I considered the phantasms that hovered around me as what they really were, namely, the effects of disease; and made them subservient to my observations, because I consider observation and reflection as the basis of all rational philosophy." PART IV. CHAPTER I. GENERAL OBJECT OF THE INVESTIGATION WHICH FOLLOWS. Next, for 'tis time, my muse declares and sings, By day they meet, and strike our minds, and fright, A FIT opportunity now occurs for more explicitly stating the plan upon which this dissertation has been hitherto conducted, as well as its ultimate object. In the first place, a general view was given of the particular morbid affections with which the production of phantasms is often connected. Apparitions were likewise considered as nothing more than ideas, or the recollected images of the mind, which had been rendered more vivid than actual impressions. In another part of this work, my object was to |