Is there a Fourth Dimension: and, if so, what is it?—Such are the questions propounded by Mr, C. H. Hinton, B. in' a fascinating but eminently tan tal ing little brochure which is apparently the first of a series called ' Soientifio Romances,' To the first question, the author appears to give an affirmative reply, in so far as he shows, clearly enough, that, reasoning by analogy, we have much cause to believe in its ex. istence, Ho argues, indeed, not only that there may be, and probably is, a Fourth Dimevsion, but that space itself—the apace or sphere in which we live—may be four-dimeusiounl, and we ourselves unconscious of it. It is, of course, impossible to represent to our minds @ space of four dimovsions; but analogy steps in, and peremptorily for. bids us to argue the non-existence of such a condition from the mere foot of our inability to conceive it, For example, we can ensily imagine the istence of @ creature in one-dimensional space. Such a creature would be cons tained in a finite straight line, and could only move backwards and forwards in the same lino; and he, consequently, could not conceive of a two-dimensional state, Then, suppose a person confined toa plane: and of such a being wean form a very good ides from the moving figures thrown upon a sheet by a magly lantern, particularly if they are without any perspective whatever, no as to look absolutely flint, Such a person could only move in two directions. If the surface which forms the sphere of his existence be horizontal—aud here the figures thrown upon a table by a camera obsoura exactly represent the two-dimensional porsou=-the denizen of Flatland would be unable to conceive anything above, or outside, that plane: ho would have no ides of up,' or, supposing the plane to be perpendicular, of out;' his entire range of experieuve and speculation: would be confined to movements upon a flat surface, and a three-dimensional space would be: beyond his utmost thought. But now let us go a step farther, We have supposed our denizen of Flatland, or two-dimensional space, avd, by the hypothesis, he has no conception of the Third Dimension; and yet, as we know, the Third: Dimousion exists. The reason of this is either that Lo la of only two. dimensions himeelf, or cive so extremely thin ax to be aucouscious that Lo has any thickuegy.
Text read from the printed page and cleaned; old type leaves the occasional error.