each dimension of space adds a new fundamental variety to form; if to illustrate this I may use a simile I have often used, it may perhaps convey to you a little idea of what I mean. Two similes I will take each throwing a little light on a very difficult subject. Suppose that a picture is presented to you of a solid form; the picture, being made by pen or pencil on a sheet of paper, must show on the sheet, which is practically of two dimensions--a plane surface--a three dimensional form; so that if you want to represent a solid object, a vase, you must draw it flat, and you can only represent the solidity of that vase by resorting to certain devices of light and shade, to the artificial device which is called perspective, in order to make an illusory semblance of the third dimension. There on the plane surface you get a solid appearance, and the eye is deceived into thinking it sees a solid when really it is looking at a flat surface. Now as a matter of fact if you show a picture to a savage, an undeveloped savage, or to a very young child, they will not see a solid but only a flat. They will not recognise the picture as being the picture of a solid object they have seen in the world round them; they will not see that that artificial representation is meant to show a familiar solid, and it passes by them without making any impression on the mind; only the education of the eye enables you to see on a flat surface the picture of a solid form. Now, by an effort of the imagination, can you think of a solid as being the representation of a form in one dimension more, shown by a kind of perspective? Then you may get a vague idea of what is meant when we speak of a further dimension in space. As the picture is to the vase, so is the vase to a higher object of which that vase itself is a reflection. So again if you think, say, of the lotus flower I spoke of yesterday, as having just the tips of its leaves above water, each tip would appear as a separate object. If you know the whole you know that they are all parts of one object; but coming over the surface of the water you will see tips only, one for each leaf of the seven-leaved lotus. So is every globe in space an apparently separate object, while in reality it is not separated at all, but part of a whole that exists in a space of more dimensions; and the separateness is mere illusion due to the limitations of our faculties.