Now here we have a perfectly plain narrative, clear and full. A ghost appeared; he is described distinctly. How can we account for the apparition? In the first place, someone might have played a trick, but that idea was put aside by Dr. Wilks, who attempted to explain the appearances. He went fully into the question, and as it bears upon our explanation of the reality of Spectral Illusions, we may condense his evidence. It will of course be conceded that all the usual objects seen by people are material, and the image of what we look at is formed upon the retina in the manner already explained. But _all_ images upon the retina are not immediately observed; the impression may, to a certain extent, remain. Words are often impressed upon the brain,—words which we in our sober senses would never think of repeating,—and yet when we are delirious we give vent to these expressions, of whose very nature and meaning we are perfectly unconscious. It is, according to our reference (Dr. Wilks), “quite possible for the perceptive part of the brain to be thrown into an active condition quite independent of the normal stimulus conducted to it from the retina.” If, under these circumstances, an object be viewed independently, and, as it were, unconsciously, it is merely, we believe, a parallel to the impression of words before noted. Sound and light are governed by the same laws. In fevers we fancy we see all kinds of things which have no existence. In dreams we hear noises; and many a time people dreaming have been awakened by the report of a gun, or the ringing of a bell which had no material origin,—the nerves were excited, the “perceptive centre” of the brain was moved. But if sight and hearing thus have their origin from the _brain_ and not from without, there must have been some predisposing cause, some excitement to induce such a condition of things. “The impressions become abnormal and subjective,—the normal condition being objective,—the impression is received from without, and impressed upon the eye. Now, let us consider the “ghost”! Lately there have been many instances brought forward of “spiritual” appearances, but we think nobody has ever seen a “_material_” ghost; yet on the other hand none of us have any knowledge of anything in the likeness of a ghost, or that _has not a material basis_ which _can_ bring forward an image on the retina! Therefore we are brought to the conclusion that apparitions are spectres emanating from within the brain, not from any outward manifestation, because it is within the experience of everybody that in bad health, or disordered digestive functions, images are produced in the brain and nerves of the eye.