The oceanic theory, and the doctrine of the Four Worlds, as it has been termed,[288]_ terra quadrifiga_, was set forth in the greatest detail in a commentary on the Dream of Scipio, written by Macrobius, probably in the fifth century a.d. In the concussion and repulsion of the ocean streams he found a sufficient cause for the phenomena of the tides.[289] Such were the theories of the men of science, purely speculative, originating in logic, not discovery, and they give no hint of actual knowledge regarding those distant regions with which they deal. From them we turn to examine the literature of the imagination, for geography, by right the handmaid of history, is easily perverted to the service of myth. [Illustration: MACROBIUS After Santarem’s _Atlas_, as a “mappemonde tirée d’un manuscrit de Macrobe du Xème siècle.”] The expanding horizon of the Greeks was always hedged with fable: in the north was the realm of the happy Hyperboreans, beyond the blasts of Boreas; in the east, the wonderland of India; in the south, Panchæa and the blameless Ethiopians; nor did the west lack lingering places for romance. Here was the floating isle of Æolus, brazen-walled; here the mysterious Ogygia, navel of the sea;[290] and on the earth’s extremest verge were the Elysian Fields, the home of heroes exempt from death, “where life is easiest to man. No snow is there, nor yet great storm nor any rain, but always ocean sendeth forth the breeze of the shrill west to blow cool on men.”[291] Across the ocean river, where was the setting of the sun, all was changed. There was the home of the Cimmerians, who dwelt in darkness; there the grove of Persephone and the dreary house of the dead.[292] In the Hesiodic poems the Elysian Fields are transformed into islands, the home of the fourth race, the heroes, after death:— “Them on earth’s utmost verge the god assign’d A life, a seat, distinct from human kind: Beside the deepening whirlpools of the main, In those blest isles where Saturn holds his reign, Apart from heaven’s immortals calm they share A rest unsullied by the clouds of care: And yearly thrice with sweet luxuriance crown’d Springs the ripe harvest from the teeming ground.”[293] “Those who have had the courage to remain stedfast thrice in each life, and to keep their souls altogether from wrong,” sang Pindar, “pursue the road of Zeus to the castle of Cronos, where o’er the isles of the blest ocean breezes blow, and flowers gleam with gold, some from the land on glistering trees, while others the water feeds; and with bracelets of these they entwine their hands and make crowns for their heads.”[294]