This Circumstance seems to have the Marvellous without the Probable, because it is represented as proceeding from Natural Causes, without the Interposition of any God, or other Supernatural Power capable of producing it.  The Spears and Arrows grow of themselves, without so much as the Modern Help of an Enchantment.  If we look into the Fiction of Milton’s Fable, though we find it full of surprizing Incidents, they are generally suited to our Notions of the Things and Persons described, and tempered with a due Measure of Probability.  I must only make an Exception to the Limbo of Vanity, with his Episode of Sin and Death, and some of the imaginary Persons in his Chaos.  These Passages are astonishing, but not credible; the Reader cannot so far impose upon himself as to see a Possibility in them; they are the Description of Dreams and Shadows, not of Things or Persons.  I know that many Criticks look upon the Stories of Circe, Polypheme, the Sirens, nay the whole Odyssey and Iliad, to be Allegories; but allowing this to be true, they are Fables, which considering the Opinions of Mankind that prevailed in the Age of the Poet, might possibly have been according to the Letter.  The Persons are such as might have acted what is ascribed to them, as the Circumstances in which they are represented, might possibly have been Truths and Realities.  This Appearance of Probability is so absolutely requisite in the greater kinds of Poetry, that Aristotle observes the Ancient Tragick Writers made use of the Names of such great Men as had actually lived in the World, tho the Tragedy proceeded upon Adventures they were never engaged in, on purpose to make the Subject more Credible.  In a Word, besides the hidden Meaning of an Epic Allegory, the plain litteral Sense ought to appear Probable.  The Story should be such as an ordinary Reader may acquiesce in, whatever Natural, Moral, or Political Truth may be discovered in it by Men of greater Penetration.

Satan, after having long wandered upon the Surface, or outmost Wall of the Universe, discovers at last a wide Gap in it, which led into the Creation, and is described as the Opening through which the Angels pass to and fro into the lower World, upon their Errands to Mankind.  His Sitting upon the Brink of this Passage, and taking a Survey of the whole Face of Nature that appeared to him new and fresh in all its Beauties, with the Simile illustrating this Circumstance, fills the Mind of the Reader with as surprizing and glorious an Idea as any that arises in the whole Poem.  He looks down into that vast Hollow of the Universe with the Eye, or (as Milton calls it in his first Book) with the Kenn of an Angel.  He surveys all the Wonders in this immense Amphitheatre that lye between both the Poles of Heaven, and takes in at one View the whole Round of the Creation.