For simple and recurrent forms of hallucination, much may be said in favour of the lower origin. It is in accordance with all that we know or conjecture as to nerve-tissue, that certain cell-modifications and radiations of discharge would be rendered easy by exercise; and thus the changes to which any morbid excitement gives rise might naturally be the same as have often before been brought about by normal stimulation from the retina or the ear. The elements would fall readily, so to speak, into the accustomed pattern. An object which has been frequently or recently before the eyes, a word or phrase that has been perpetually in the ear - these may certainly be held capable of leaving organic traces of their presence, and so of establishing a sort of lower memory; as markedly shown, for instance, in cases where uneducated persons have in delirium recited passages of some strange language, of which the sound but not the sense has at some past time been familiar to them. That this lower memory should act automatically seems natural enough when we remember how large a part even of the higher memory is also automatic: an unsought word, suddenly reverberating in the sensorium, is on a par with the images that emerge into consciousness without our being able to connect them with our previous train of ideas.

Now it is remarkable how large a number of hallucinations are of this primitive type. I mentioned above that, among the sane, the commonest of all cases is to hear the name called; and even with the insane, the vocabulary of the imaginary voices often consists of only a few words, usually threatening or abusive, but mark out as the visual and the auditory centres; while lesions at these spots - the angular gyrus and the first temporo-spenoidal convolution - seem to bo found in cases where no hallucination has been observed. (Journal of Mental Science, Oct., 1881, p. 381, and Jan., 1882, p. 29.) This want of correspondence will seem less surprising, if we remember that in the vast number of casual hallucinations nothing that could be called a lesion exists; that for the delusions of sleep, of the delirium of fever, of fasting, of the early stages at any rate of hashish and opium-eating, only the general physiological explanation can be given that they are due to some change in the constitution or distribution of the blood; and also that the more persistent hallucinations of the insane belong, as a rule, to the earlier period of irritation, rather than to the later one when marked lesion has supervened, and dementia is creeping on.

Even if we take subsequent cortical lesion as a sign that the weak spot existed from the first in the highest part of the brain, this would be no proof that the specific sensory centre is cortical. If lesions are not bound to be locally restricted, much less are irritations; and there is nothing to refute the supposition above made, that, when the hallucination occurs, a current has passed downwards to the lower centre - the mischief in the cortex having been primarily an excitant of ideational activities only, and the hallucination being due (as Dr. Mickle well expresses it) to "a tumultuous disorderly reaction of disturbed ideational centres upon sensorial." The same may be said of the artificial irritation of the "cortical centres" during life. Ferrier regards the movements which result when an electrical stimulus is applied to these areas, as an indication that visual or auditory sensations (i.e., hallucinations) have been evoked. Wo may quite accept this interpretation, but still suppose that the primary seat of the sensation was not the spot where the stimulus was applied, but a lower centre on the path along which the irritation passed.

"One day, after having spent a considerable time in inspecting a village churchyard, what was my horror and consternation to find, on leaving it, that wherever my eyes rested I could descry nothing but monumental inscriptions. The dust on the roadside somehow seemed to form itself into letters. The macadamised highway seemed written all over with mourning, lamentation, and woe: and even when I turned my gaze to the stone dykes on either side of the way, it was only to find that, by some subtle chemistry of my brain, the weather-stains and cracks shaped themselves into words which I could plainly decipher, and found to be of the same nature as those which I had recently been reading in the churchyard. Every time that autumn and winter that I paid a visit to a churchyard, the experience recurred; and on more than one occasion also without that exciting cause".

The Rev. G. Lyon Turner, Professor of Philosophy at the Lancashire Independent. College, Manchester, tells me that he saw one night suspended from the ceiling of the room, which he knew to be plain, "A large chandelier with some 10 scroll-shaped branches, and the jets shining brightly through the ground-glass globes at the end of each. I at once recognised the chandelier as a duplicate of the chandelier which hung in the college chapel connected with the Countess of Huntingdon's college at Cheshunt, where I received my training for the ministry. I moved my head, to see whether the phantom moved too. But no, it remained fixed; and the objects behind and beyond it became more or less completely visible as I moved, exactly as would have been the case had it been a real chandelier." Mr. Turner woke his wife, who naturally saw nothing.

1On this subject see Dr. V. Parant in the Ann. Medico-psych., 6th series, vol. vii., p. 384; Kahlbaum, Op. cit., p. 5; and Kraepelin's paper, "Ueber Trugwahrneh-muugen,"in the Vierteljahrschrift fur Wissenschaftliche Philosophic for 1881, p. 225. These embryonic hallucinations often develop into more complex form; Ball, Op. cit., p. 67.

2This is a convenient description; but it must not be held to imply any retinal affection, of the sort that Hibbert, Ferrier, and Brewster supposed. See p. 292, and p.311,nete.