Note 39 — Chapter I

See Appendix, No. XII.— (vol. II.) In the Middle Ages the prevalent opinion was that the sea covered but one seventh of the surface of the globe; an opinion which Cardinal d'Ailly (Imago Mundi, cap. viii.) founded on the apocryphal fourth book of Ezra. Columbus, who always derived much of his cosmological knowledge from the cardinal's work, was much interested in upholding this idea of the smallness of the sea, to which the misunderstood expression of "the ocean-stream" contributed not a little. He was also accustomed to cite Aristotle, and Seneca, and St. Augustine, in confirmation of this opinion.—Humboldt's Examen Critique de l'Hist. de la Géographie, tom. i., p. 186.