When we proceed to inquire how the imagination of the people filled up the void of its experience, and determined the form of the unknown world, we find that the rudeness of its conceptions corresponds to the scantiness of its information. The part of the earth exposed to the beams of the sun was undoubtedly considered, not as a spherical, but as a plane surface, only varied by its heights and hollows; and, as little can it be doubted, that the form of this surface was determined by that of the visible horizon. The whole orb is girt by the ocean, not a larger sea, but a deep river, which, circulating with constant but gentle flux, separates the world of light and life from the realms of darkness, dreams, and death. No feature in the Homeric chart is more distinctly prominent than this: hence the divine artist terminates the shield of Achilles with a circular stripe, representing “the mighty strength of the river _Ocean_,” and all the epithets which the poet applies to it are such as belong exclusively to a river. Homer describes all the other rivers, all springs and wells, and the salt main itself, as issuing from the ocean stream, which might be supposed to feed them by subterraneous channels. Still it is very difficult to form a clear conception of this river, or to say how the poet supposed it to be bounded. Ulysses passes into it from the western sea; but whether the point at which he enters is a mouth or opening, or the two waters are only separated by an invisible line, admits of much doubt. On the farther side however is land: but a land of darkness, which the sun cannot pierce, a land of Cimmerians, the realm of Hades, inhabited by the shades of the departed, and by the family of dreams. As to the other dimensions of the earth, the poet affords us no information, and it would be difficult to decide whether a cylinder or a cone approaches nearest to the figure which he may have assigned to it: and as little does he intimate in what manner he conceives it to be supported. But within it was hollowed another vast receptacle for departed spirits, perhaps the proper abode of Hades. Beneath this, and as far below the earth as heaven was above it, lay the still more murky pit of Tartarus, secured by its iron gates and brazen floor, the dungeon reserved by Jupiter for his implacable enemies.