Captain Scoresby, in his voyage to the arctic regions, on the coast of East Greenland, constantly saw those visionary cities, and gives some highly curious plates of the appearances they presented. They resembled the real cities seen on the coast of Holland, where towers, and battlements, and spires, "bosomed high in tufted trees," rise on the level horizon, and are seen floating on the surface of the sea. Among the optic deceptions noticed by Captain Scoresby, was one of a very singular nature. His ship had been separated by the ice, from that of his father for some time; and he was looking for her every day, with great anxiety. At length, one evening, to his utter astonishment, he saw her suspended in the air in an inverted position, traced on the horizon in the clearest colours, and with the most distinct and perfect representation. He sailed in the direction in which he saw this visionary phenomenon, and actually found his father's vessel by its indication. He was divided from him by immense masses of icebergs, and at such a distance that it was quite impossible to have seen the ship in her actual situation, or seen her at all, if her spectrum, or image, had not been thus raised several degrees above the horizon into the sky, by this most extraordinary refraction, in the same manner as the sun is often seen, after he is known to have set, and actually sunk far below the line of direct vision. The _Fata Morgana_ are further illustrations of this optic delusion. This phenomenon is seen at the Pharo of Messina, in Sicily, under certain circumstances. The spectator must stand with his back to the east, on an elevated place behind the city, commanding a view of the bay, and having the mountains, like a wall, opposite to him, to darken the back ground of the picture; no wind must be abroad to ruffle the surface of the sea; and the waters must be pressed up by currents, as they sometimes are, to a considerable height in the middle of the strait, and present a slight convex surface. When all these circumstances occur, as soon as the sun rises over the heights of the Calabrian shore, and makes an angle of 45º with the horizon, all the objects on the shore at Reggio are transferred to the middle of the strait, and seen distinctly on the surface of the water, forming an immoveable landscape of rocks, trees, and houses, and a moveable one of men, horses, and cattle; these are formed into a thousand separate compartments, presenting most beautiful and ever varying pictures of animate and inanimate nature, on the swelling surface of the water, broken by the currents, present separate plates of convex mirrors to reflect them; they then as suddenly disappear, as the broad aquatic mirror of the current passes on.