On such occasions as we have hitherto mentioned, we have supposed that the ghost-seer has been in full possession of his ordinary powers of perception, unless in the case of dreamers, in whom they may have been obscured by temporary slumber, and the possibility of correcting vagaries of the imagination rendered more difficult by want of the ordinary appeal to the evidence of the bodily senses. In other respects their blood beat temperately, they possessed the ordinary capacity of ascertaining the truth or discerning the falsehood of external appearances by an appeal to the organ of sight. Unfortunately, however, as is now universally known and admitted, there certainly exists more than one disorder known to professional men of which one important symptom is a disposition to see apparitions. This frightful disorder is not properly insanity, although it is somewhat allied to that most horrible of maladies, and may, in many constitutions, be the means of bringing it on, and although such hallucinations are proper to both. The difference I conceive to be that, in cases of insanity, the mind of the patient is principally affected, while the senses, or organic system, offer in vain to the lunatic their decided testimony against the fantasy of a deranged imagination. Perhaps the nature of this collision--between a disturbed imagination and organs of sense possessed of their usual accuracy--cannot be better described than in the embarrassment expressed by an insane patient confined in the Infirmary of Edinburgh. The poor man's malady had taken a gay turn. The house, in his idea, was his own, and he contrived to account for all that seemed inconsistent with his imaginary right of property--there were many patients in it, but that was owing to the benevolence of his nature, which made him love to see the relief of distress. He went little, or rather never abroad--but then his habits were of a domestic and rather sedentary character. He did not see much company--but he daily received visits from the first characters in the renowned medical school of this city, and he could not therefore be much in want of society. With so many supposed comforts around him--with so many visions of wealth and splendour--one thing alone disturbed the peace of the poor optimist, and would indeed have confounded most _bons vivants_. "He was curious," he said, "in his table, choice in his selection of cooks, had every day a dinner of three regular courses and a dessert; and yet, somehow or other, everything he eat _tasted of porridge_." This dilemma could be no great wonder to the friend to whom the poor patient communicated it, who knew the lunatic eat nothing but this simple aliment at any of his meals. The case was obvious. The disease lay in the extreme vivacity of the patient's imagination, deluded in other instances, yet not absolutely powerful enough to contend with the honest evidence of his stomach and palate, which, like Lord Peter's brethren in