[16] A further interesting question regarding the dream-vision of the partially blind is, How much must they be able to see in order to dream of seeing? In answering this question, the blind give the name "seeing" to what is really a complex of sensations and judgments, and this same complex may enter into their dreams. Cases occur in which there is only the slightest remnant of sight, and yet this forms a factor in dream-life. It is a very imperfect kind of vision, and acts more as a general sense of illumination, and as an anticipatory sense. Generally speaking, those who know color have more frequent and brighter dream-vision than those who distinguish light and shade only. For example, of those partially blind from birth, such as see color tolerably well (there are sixteen such) have regular dream-vision--of course, no clearer than their best days of sight. Of eleven who have some faint notion of color, three have dream-vision regularly; six have it rarely, while two (almost never or) never have it. Of eleven who can see no color at all, ten have no dream-vision, and one has it occasionally. [17] That even a comparatively slight disturbance of vision, affecting only a small portion of the visual experience, can leave a permanent trace upon the sight-centre is made very probable by a case (recorded by Dr. McCosh, _Cognitive Powers_, p. 106) of a young man whose defect consisted in his seeing everything double,--a defect which a subsequent operation removed. "If I attempt," he writes, "to recall scenes that I saw while my eyes were out of order, I invariably see them as they appeared during that time, although I may have seen them many times since the operation. For instance, in the case of the minister in the pulpit at home, I see two images of him, no matter how much I may try to get rid of one of them.... My recollection of the office in which the operation was performed, as also of everything in it, is double, although I saw it only twice before the restoration of my sight, and many times after. The objects which I have seen since the operation are always single when recalled." [18] I have gathered considerable data in regard to the dreams of the deaf, but they are not ready for definite formulation. [19] From Dr. Hall's manuscript. Dr. Hall had the opportunity of observing her during three short naps, and has incorporated a part of his manuscript into a paper on Laura Bridgman, republished in his _Aspects of German Culture_, pp. 268-270. From this manuscript I take the following illustrations of her dreams, and her method of describing them. They are recorded verbatim.