So, then, gathering together this which is discussed, it seems that there may be ten Heavens, of which the Heaven of Venus may be the third; whereof mention is made in that part which I intend to demonstrate. And it is to be known that each Heaven below the Crystalline has two firm poles as to itself; and the ninth has them firm and fixed, and not mutable in any respect. And each one, the ninth even as the others, has a circle, which one may term the equator of its own Heaven; which equally, in each part of its revolution, is remote from one pole and from the other, as he who rolls an apple or any other round thing can sensibly perceive. And this circle has more swiftness in its movement than any other part of its Heaven, in each Heaven, as he may perceive who considers well. And each part, in proportion as it is nearer to it, moves so much the more swiftly; so much the slower in proportion as it is more remote and nearer to the pole; since its revolution is less, and it must of necessity be in one self-same time with the greater. I say again, that in proportion as the Heaven is nearer to the equatorial circle, so much the more noble is it in comparison to its poles; since it has more motion and more actuality and more life and more form and more touch from that which is above itself, and consequently has more virtue. Hence the stars in the Heaven of the fixed stars are more full of power amongst themselves in proportion as they are nearer to that circle. And upon the back of this circle in the Heaven of Venus, of which I now speak, is a little sphere, which revolves by itself in this Heaven, the circle of which Astrologers call Epicycle; and as the great sphere revolves about two poles, so does this little sphere: and so has this little sphere the equatorial circle; and so much the more noble it is in proportion as it is nearer to those: and in the arc, or rather back, of this circle is fixed the most brilliant star of Venus. And, although it may be said that there are ten Heavens according to strict Truth, this number does not comprehend them all: for that of which mention is made, the Epicycle, in which the star is fixed, is a Heaven by itself, or rather sphere; and it has not one essence with that which bears it, although it may be more like to it than to the others, and with it is called one Heaven, and they name the one and the other from the star. How the other Heavens and the other stars may be is not for present discussion; let it suffice that the nature of the third Heaven, with which I am at present concerned, has been told, and concerning which all that is at present needful has been shown. CHAPTER V.