remained unchanged as long as it was visible at all; like a perception, it stood still to be scrutinized, though it yielded no more detail than at the first glance. Occasionally, when the first appearance of the image was incomplete or otherwise unsatisfactory, transformations would be observed in the defective parts, or the entire image would flicker out, and a new one would take its place.[1]
Usually the image was on, or at the exact distance of, the wall. Sometimes, especially for V, it was nearer, and induced a "cross-eye feeling"; the point of fixation could then be roughly determined by passing the finger back and forth through the image and noting double-images. If the object imaged were too large for the field of vision at the distance of the wall, the perception of distance was rather uncomfortably disturbed; the image was 'felt' to be at the distance of the wall, but was of a size that the imaged object should have had at a greater distance. The wall, under these conditions, dropped out of consciousnes, or remained only to color the atmosphere surrounding the image.
A series of 20 tests gave the average duration of V's images as about 90 sec. The maximal duration noted was nearly 180 sec. If an effort was made to hold the image to the bitter end, it grew smaller and less distinct, receded in space, and finally faded out. Otherwise, it simply ceased to be there.
We may add the general statement that both P and V frequently reported absence of bodily movement, and lack of diffused kinæsthetic sensations, especially after comparing these images with the images of memory.
Memory. These images did not involve a steady fixation, but rather a definite eye-movement; the observer was conscious of seeking them in a definite direction.[2] The image appeared with a determinate orientation to the observer, which might, however, differ widely from that of the original experience. When once the image had appeared, the observer could very rarely, and then only with the greatest effort of attention, get it with any other orientation; if he succeeded, the image
- ↑ Several experimenters have reported oscillation or fluctuation of the image. V sometimes noticed fluctuations, at first of a period of some 40 sec., and then of increasing frequency. Fluctuation seems to vary not only with the individual, but also with the condition of the individual. Cf. Moore: op. cit., 295.
Both observers found that the image flickered with winking, and that if the eyes were closed it usually disappeared or, at best, remained for a very short time. - ↑ This point has been noticed by many investigators: Fechner, Kuhlmann, Meakin, Moore, Murray, Slaughter.
