The Romans and the Persians called the line of the axis of the globe cardo, and it was to cardo the needle pointed. Now "Cardo was the name of the mountain on which the human race took refuge from the Deluge... the primitive geographic point for the countries which were the cradle of the human race." (Urquhart's "Pillars of Hercules," vol. i., p. 145.) From this comes our word "cardinal," as the cardinal points. Navigation.--Navigation was not by any means in a rude state in the earliest times: "In the wanderings of the heroes returning from Troy, Aristoricus makes Menelaus circumnavigate Africa more than 500 years before Neco sailed from Gadeira to India." ("Cosmos," vol. ii., p. 144.) "In the tomb of Rameses the Great is a representation of a naval combat between the Egyptians and some other people, supposed to be the Phoenicians, whose huge ships are propelled by sails." (Goodrich's "Columbus," p. 29.) The proportions of the fastest sailing-vessels of the present day are about 300 feet long to 50 wide and 30 high; these were precisely the proportions of Noah's ark--300 cubits long, 50 broad, and 30 high. "Hiero of Syracuse built, under the superintendence of Archimedes, a vessel which consumed in its construction the material for fifty galleys; it contained galleries, gardens, stables, fish-ponds, mills, baths, a temple of Venus, and an engine to throw stones three hundred pounds in weight, and arrows thirty-six feet long. The floors of this monstrous vessel were inlaid with scenes from Homer's 'Iliad.'" (Ibid., p. 30.) The fleet of Sesostris consisted of four hundred ships; and when Semiramis invaded India she was opposed by four thousand vessels. It is probable that in the earliest times the vessels were sheeted with metal. A Roman ship of the time of Trajan has been recovered from Lake Ricciole after 1300 years. The outside was covered with sheets of lead fastened with small copper nails. Even the use of iron chains in place of ropes for the anchors was known at an early period. Julius Cæsar tells us that the galleys of the Veneti were thus equipped. (Goodrich's "Columbus," p. 31.)