will your mind be fixed on that object? why don't you rather take a view of the magnificent temples among which you have arrived? The universe is composed of nine circles, or rather spheres, one of which is the heavenly one, and is exterior to all the rest, which it embraces; being itself the Supreme God, and bounding and containing the whole. In it are fixed those stars which revolve with never-varying courses. Below this are seven other spheres, which revolve in a contrary direction to that of the heavens. One of these is occupied by the globe which on earth they call Saturn. Next to that is the star of Jupiter, so benign and salutary to mankind. The third in order is that fiery and terrible planet called Mars. Below this, again, almost in the middle region, is the sun—the leader, governor, and prince of the other luminaries; the soul of the world, which it regulates and illumines; being of such vast size that it pervades and gives light to all places. Then follow Venus and Mercury, which attend, as it were, on the sun. Lastly, the moon, which shines only in the reflected beams of the sun, moves in the lowest sphere of all. Below this, if we except that gift of the Gods, the soul, which has been given by the liberality of the Gods to the human race, everything is mortal, and tends to dissolution; but above the moon all is eternal. For the earth, which is the ninth globe, and occupies the centre, is immovable, and, being the lowest, all others gravitate towards it.
XVIII. When I had recovered myself from the astonishment occasioned by such a wonderful prospect, I thus addressed Africanus: Pray what is this sound that strikes my ears in so loud and agreeable a manner? To which he replied: It is that which is called the music of the spheres, being produced by their motion and impulse; and being formed by unequal intervals, but such as are divided according to the justest proportion, it produces, by duly tempering acute with grave sounds, various concerts of harmony. For it is impossible that motions so great should be performed without any noise; and it is agreeable to nature that the extremes on one side should produce sharp, and on the other flat sounds. For winch reason the sphere of the fixed stars, being the highest, and
