these populous villages proferred to them. When they arrived, the lake, on whose bosom they floated, the trees, among whose foliage they were embowered, and the people who stood on the shore inviting their approach, had all vanished, and nothing remained but an uniform and irksome desert of sand and sky, with a few naked huts and ragged shrubs. Had they not been undeceived by their nearer approach, there was not a man in the French army who would not have sworn, that the visionary trees and lakes had a real existence in the midst of the desert.

The same appearance precisely was observed by Dr. Clarke at Raschid, or Rosetta. The city seemed surrounded by a beautiful sheet of water, and so certain was his Greek interpreter, who was acquainted with the country, of this fact, that he was quite indignant at an Arab, who attempted to explain to him, that it was a mere optical delusion. At length, they reached Rosetta in about two hours, without meeting any water; and, on looking back on the sand they had just crossed, it seemed to them, as if they had just waded through a vast blue lake.

A similar deception takes place in northern climates. Cities, battlements, houses, and all the accompaniments of populous places, are seen in desolate regions, where life goes out, and where human foot has never trod. When approached they vanish, and nothing remains but a rugged rock, or a misshapen iceberg.

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 45° 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.

Sometimes the atmosphere is so dense that the objects are seen, like Captain Scoresby's ship, snatched up into the regions of the air, thirty or forty feet above the level of the sea; and in cloudy weather, nearer to the surface, bordered with vivid prismatic colours. Sometimes colonades of temples and churches, with cross-crowned spires, are all represented as floating on the sea, and by a sudden change of representation, the pillars are curved into arcades, and the crosses are bent into crescents, and all the edifices of the floating city undergo the most extraordinary and fantastic mutations. All these images are so distinct, and produce objects seemingly as palpable as they are visible, as sensible to touch as to

sight, that the people of the country are firmly persuaded of their reality. They consider the edifices as the enchanted palaces of the fairy Morgana, and the moving objects as living things which inhabit them. Whenever the optic phenomenon occurs, they meet together in crowds, with an intense curiosity, mixed with awe and apprehension, which is not removed by an acquaintance with those natural causes, by which Mr. Swinburn and other foreign travellers, who have witnessed the scene, are able to account for it.

The lakes of Ireland are equally susceptible of pro. ducing those vivid delusions, and the imagination of the people, as lively as that of the Sicilians, clothes them with an equal reality. There is scarcely a loch in that country, in which the remains of cities have not been at various times discovered; and many men have been met with who would solemnly swear they saw, and who no doubt did see, representations of them in certain states of the atmosphere. The most celebrated is that which occurs on the lake of Killarney. This romantic sheet of water is bounded on one side by a semi-circle of rugged mountains, and on the other by a flat morass, and the vapour generated in the mass, and broken by the mountains, continually represent the most fantastic objects; and often those on shore are transferred to the water, like the Fata Morgana.

Many of the rocks are distinguished for their marked and lengthened echoes, and the structure, which in acoustics reflects sounds to the ear, from a point from whence they did not come, reflects images on the eye, from a place very different from

where the objects stood which produced them. Frequently men riding along shore, are seen as if they were moving across the lake, and this has given rise to the story of O'Donougho. This celebrated chieftain was, according to the tradition of the country, endued with the gift of magic; and, on one occasion, his lady requested him to change his shape, that she might see a proof of it. He complied, on condition that she would not be terrified, as such an effect on her must prove fatal to him. Her mind failed her, however, in the experiment, and at the sight of some horrible figure he assumed, she shrieked, and he disappeared through the window of his castle, which overhung the lake. From that time he continues an enchanted being, condemned to ride a horse, shod with silver, over the surface of the lake, till his horse's shoes are worn out. On every May morning he is visible, and crowds assemble on the shore to see him. Many affirm they have seen him; and one person relates many particulars of his apparition, that the deception must have proceeded from some real object, a man riding along shore, and transferred to the middle of the water, by the optic delusion of the Fata Morgana.

But perhaps the most wonderful, and apparently preternatural effect arising from this cause, is the spectre of the Hartz Mountains in Hanover. There is one particular hill, called the Brocken, in which he appears, terrifying the credulous, and gratifying the curious to a very high degree. The most distinct and interesting account is given by Mr. Hawe, who himself was a witness to it, He had

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