Satan had heard that in order to hollow out this awful place in Chaos, the ether, which was believed to fill all space, flew upward "spirited with various forms, That rowl'd orbicular, and turned to starrs." the stars walling-in a Universe which was to contain a dwelling place for a new race which might eventually take the place of the rebels cast from Heaven. The stars were then surrounded by a translucent shell which protected this new creation from the cold and tempests of outer space. Satan searched long and ardently through the darkness for this splendid ball of light. Finally he found it, hanging on its golden chain from Heaven, and, descending within by the radiant stairway of the angels, passed the stars and the planets in their sliding spheres of impalpable crystal, and discovered the earth, radiant in the brightness of the sun! Of the further adventures of Satan we need not speak, but the handling of the whole subject is masterly and brought to Milton undying fame. The idea of the crystalline spheres first came to Eudoxus in the 4th century B. C. from watching the movements of the planets among the stars. He imagined that there must be nine of these hollow, transparent globes enclosed one within the other and surrounding the quiescent body of the earth; first, the "primum mobile," which carried around all the inner spheres and communicated to them a universal motion, next a sphere for all the stars, then one for the sun, one for the moon, and one for each of the five planets then known. These spheres were conceived to be of the finest crystal, for past the wandering stars or planets, the light came penetrating from that distant sphere studded with stars. The daily movements of these stars were watched as they were carried along on their spheres, and it was seen that they moved in law and order. Noting that the planets seemed to be placed at intervals corresponding to the scale in music and being at the same time greatly impressed with the discovery that music was based on mathematics, he beautifully combined these discoveries and arrived at the entrancing conclusion that so great and orderly a movement of so many crystal spheres must give forth strains which united in a wonderful harmony of incredible volume and sweetness. The picture is enchanting--a beautiful world set in the midst of whirling, star-gemmed, crystalline globes, which by their motion, create a melody so divine that it may only be heard by the gods! With the advent of modern science, our thoughts now wing their way through unobstructed star spaces of once crystalline spheres, to the great space beyond, and find in the void of what the ancients termed "chaos," not one "sun-illuminated" universe but millions of them, some so distant that they appear no more than a filmy mist on a petal or a ghost of a fairy cloud!