Note the turning sphere — MILTON’S MINOR POEMS.

48. the turning sphere. For poetical purposes Milton everywhere adopts the popular astronomy of his day, which was based on the ancient, i.e. the Ptolemaic, or geocentric system of the universe. Copernicus had already taught the modern, heliocentric theory of the [81] solar system, and his innovations were not unknown to Milton, who, however, consistently adheres to the old conceptions. In Milton, therefore, we find the earth the centre of the visible universe, while the sun, the planets, and the fixed stars revolve about it in their several spheres. These spheres are nine in number, arranged concentrically, like the coats of an onion, about the earth, and, if of solid matter, are to be conceived as being of perfectly transparent crystal. Beginning with the innermost, they present themselves in the following order: the Moon, Mercury, Venus, the Sun, Mars, Jupiter, Saturn, the Fixed Stars, the Primum Mobile. In Par. Lost III 481, the ninth sphere appears as “that crystalline sphere whose balance weighs the trepidation talked,” and the Primum Mobile, or the first moved, becomes the tenth and outermost of the series. The last two spheres contain no stars.