"There is a distinct difference between etheric sight and astral sight, and it is the latter which seems to correspond to the fourth dimension.

"The easiest way to understand the difference is to take an example. If you looked at a man with both the sights in turn, you would see the buttons at the back of his coat in both cases; only if you used etheric sight you would see them through him, and would see the shank-side as nearest to you, but if you looked astrally, you would see it not only like that, but just as if you were standing behind the man as well.

"Or if you were looking etherically at a wooden cube with writing on all its sides, it would be as though the cube were glass, so that you could see through it, and you would see the writing on the opposite side all backwards, while that on the right and left sides would not be clear to you at all unless you moved, because you would see it edgewise. But if you looked at it astrally you would see all the sides at once, and all the right way up, as though the whole cube had been flattened out before you, and you would see every particle of the inside as well—not through the others, but all flattened out. You would be looking at it from another direction, at right angles to all the directions that we know.

"If you look at the back of a watch etherically you see all the wheels through it, and the face through them, but backwards; if you look at it astrally, you see the face right way up and all the wheels lying separately, but nothing on the top of anything else."

Here we have at once the keynote, the principal factor of the change; the man is looking at everything from an absolutely new point of view, entirely outside of anything that he has ever imagined before. He has no longer the slightest difficulty in reading any page in a closed book, because he is not now looking at it through all the other pages before it or behind it, but is looking straight down upon it as though it were the only page to be seen. The depth at which a vein of metal or of coal may lie is no longer a barrier to his sight of it, because he is not now looking through the intervening depth of earth at all. The thickness of a wall, or the number of walls intervening between the observer and the object, would make a great deal of difference to the clearness of the etheric sight; they would make no difference whatever to the astral sight, because on the astral plane they would not intervene between the observer and the object. Of course that sounds paradoxical and impossible, and it is quite inexplicable to a mind not specially trained to grasp the idea; yet it is none the less absolutely true.

This carries us straight into the middle of the much-vexed question of the fourth dimension—a question of the deepest interest, though one that we cannot pretend to discuss in the space at our disposal. Those who wish to study it as it deserves are recommended to begin with Mr. C. H. Hinton's Scientific Romances or Dr. A. T. Schofield's Another World, and then follow on with the former author's larger work, A New Era of Thought. Mr. Hinton not only claims to be able himself to grasp mentally some of the simpler fourth-dimensional figures, but also states that anyone who will take the trouble to follow out his directions may with perseverance acquire that mental grasp likewise. I am not certain that the power to do this is within the reach of everyone, as he thinks, for it appears to me to require considerable mathematical ability; but I can at any rate bear witness that the tesseract or fourth-dimensional cube which he describes is a reality, for it is quite a familiar figure upon the astral plane. He has now perfected a new method of representing the several dimensions by colours instead of by arbitrary written symbols. He states that this will very much simplify the study, as the reader will be able to distinguish instantly by sight any part or feature of the tesseract. A full description of this new method, with plates, is said to be ready for the press, and is expected to appear within a year, so that intending students of this fascinating subject might do well to await its publication.

I know that Madame Blavatsky, in alluding to the theory of the fourth dimension, has expressed an opinion that it is only a clumsy way of stating the idea of the entire permeability of matter, and that Mr. W. T. Stead has followed along the same lines, presenting the conception to his readers under the name of throughth. Careful, oft-repeated and detailed investigation does, however, seem to show quite conclusively that this explanation does not cover all the facts. It is a perfect description of etheric vision, but the further and quite different idea of the fourth dimension as expounded by Mr. Hinton is the only one which gives any kind of explanation down here of the constantly-observed facts of astral vision. I would therefore venture deferentially to suggest that when Madame Blavatsky wrote as she did, she had in mind etheric vision and not astral, and that the extreme applicability of the phrase to this other and higher faculty, of which she was not at the moment thinking, did not occur to her.

The possession of this extraordinary and scarcely expressible power, then, must always be borne in mind through all that follows. It lays every point in the interior of every solid body absolutely open to the gaze of the seer, just as every point in the interior of a circle lies open to the gaze of a man looking down upon it.

But even this is by no means all that it gives to its possessor. He sees not only the inside as well as the outside of every object, but also its astral counterpart. Every atom and molecule of physical matter has its corresponding astral atoms and molecules, and the mass which is built up out of these is clearly visible to our clairvoyant. Usually the astral of any object projects somewhat beyond the physical part of it, and thus metals, stones and other things are seen surrounded by an astral aura.

It will be seen at once that even in the study of inorganic matter a man gains immensely by the acquisition of this vision. Not only does he see the astral part of the object at which he looks, which before was wholly hidden from him; not only does he see much more of its physical constitution than he did before, but even what was visible to him before is now seen much more clearly and truly. A moment's consideration will show that his new vision approximates much more closely to true perception than does physical sight. For example, if he looks astrally at a glass cube, its sides will all appear equal, as we know they really are, whereas on the physical plane he sees the further side in perspective—that is, it appears smaller than the nearer side, which is, of course, a mere allusion due to his physical limitations.