In a mind excited or exhausted, the natural sympathy between the _brain_ and the _stomach_ is wrought up to an extreme. And in the two most interesting cases of spectral illusion on record, this instance is beautifully illustrated. The bookseller of Berlin, Nicolai (whose phantasms are become so hackneyed a tale in the records of Psychology), had been thus mentally excited. It were long to repeat the circumstantial and scientific detail of his waking visions: of his ghosts of departed friends, and of strangers to him, and of the groups of shadowy figures which glided through his chamber at these spectral levees; and how his philosophic mind distinguished the intrusion of the spectre at the door and the real friend to whom its opening gave admittance; and how they disappeared when he shut his eyes, and came again as he opened his lids; or how he was at last amused by his analysis of all these illusive spectra. But the sympathy to which I have alluded will be efficiently proved by one quotation from the Prussian’s recital. During the time leeches were applied to his temples, his chamber was crowded with phantoms. “This continued uninterruptedly till about half-past four o’clock, when my digestion commenced. I then fancied that they began to move more slowly: soon after, their colour began to fade, and at seven o’clock they were entirely white: then they seemed to dissolve in the air, while fragments of some of them continued visible a considerable time.” On other occasions, they attempted to re-appear, and changed to white, more and more faintly as his health improved. There is equal interest, both for science and curiosity, in the illusion of Mrs. A. (as told by Brewster, in his “Natural Magic”), and which sprung from the like causes. The sympathetic sensitiveness of this lady was so acute, that an expression of pain in another produced it in the _corresponding_ part of herself. And she, too, was intruded on by spectres of men and women, and cats and carriages, and by corpses in shrouds peering over her shoulder at her toilet-glass, and ghastly likenesses of gentlemen in grave-clothes, sitting unceremoniously in arm chairs in her drawing-room. And yet the perfect restoration of the lady’s health was coincident with her _complete_ freedom from these spectral visitations. You will read in the Anatomie of Melancholy, that “Eremites and anchorites have frequently such absurd visions and revelations, by reason of much fasting.” In exhaustion, too, or on the approach of vertigo, if we shut our eyes, we seem as if turning round ourselves, and if we open them, then this whimsical movement is referred to the chairs and tables in our chamber. These, then, are the remote sympathies with the organs of digestion; and this chiefly by the derangement of the circulation of the blood, between the brain and the heart.