Of exactly similar nature, though far greater in degree, are the difficulties experienced by a clairvoyant in his attempt to describe upon the physical plane what he has seen upon the astral; and they are furthermore greatly enhanced by the fact that, instead of having merely to recall to the minds of his hearers conceptions with which they are already familiar, as the artist does when he paints men or animals, fields or trees, he has to endeavour by the very imperfect means at his disposal to suggest to them conceptions which in most cases are absolutely new to them. Small wonder then that, however vivid and striking his descriptions may seem to his audience, he himself should constantly be impressed with their total inadequacy, and should feel that his best efforts have entirely failed to convey any idea of what he really sees. And we must remember that in the case of the report given down here of a record read on the mental plane, this difficult operation of transference from the higher to the lower has taken place not once but twice, since the memory has been brought through the intervening astral plane. Even in a case where the investigator has the advantage of having developed his mental faculties so that he has the use of them while awake in the physical body, he is still hampered by the absolute incapacity of physical language to express what he sees. Try for a moment to realize fully what is called the fourth dimension, of which we said something in an earlier chapter. It is easy enough to think of our own three dimensions--to image in our minds the length, breadth and height of any object; and we see that each of these three dimensions is expressed by a line at right angles to both of the others. The idea of the fourth dimension is that it might be possible to draw a fourth line which shall be at right angles to all three of those already existing. Now the ordinary mind cannot grasp this idea in the least, though some few who have made a special study of the subject have gradually come to be able to realize one or two very simple four-dimensional figures. Still, no words that they can use on this plane can bring any image of these figures before the minds of others, and if any reader who has not specially trained himself along that line will make the effort to visualize such a shape he will find it quite impossible. Now to express such a form clearly in physical words would be, in effect, to describe accurately a single object on the astral plane; but in examining the records on the mental plane we should have to face the additional difficulties of a fifth dimension! So that the impossibility of fully explaining these records will be obvious to even the most superficial observation.