by hardier species of the feathered family, which the gathering storms of more northern regions had warned to leave their summer haunts.

If from the inferior animal creation, we turn to man, the same traces of a paternal hand are seen in providing against, or compensating for, the privations of winter. If our natural instincts and defences are not so numerous as those of the brutes, reason and foresight amply supply their place. Influenced by these, we build comfortable houses, of materials which are every where to be found, and collect supplies of fuel from bogs and forests, or dig them out of the bowels of the earth, where they are laid up as in storehouses; and we rear flocks and herds to furnish us with the means of food and clothing. Meanwhile, necessary industry occupies and cheers the dreary season; and books or social intercourse improve and exhilarate the mind.

All these proofs of paternal care deserve and will obtain a separate consideration; but the simple mention of them, is calculated to call forth sentiments of pious admiration and gratitude. "Who knoweth not in all these, that the hand of the Lord hath wrought this."

SECOND WEEK-MONDAY.

PHOSPHORESCENCE.

THE meteor known by the name of ignis fatuus, is connected, as I observed in the paper of Saturday, with some other luminous appearances, by this common property, that it gives out no sensible heat. Among other animals which possess the property of shining with a cold light, I mentioned the Medusa class, which sometimes illuminate the whole surface of the sea, and, in a dark night, show like a stream of liquid fire in the wake of a ship. But, besides these, there is a great variety of the

inhabitants of the ocean, which have it in their power to emit a kind of phosphoric light from their bodies at pleasure; and this remarkable property is probably given them by the Creator, to enable them to pursue their prey in the dark abysses of the sea, where the beams of the sun cannot penetrate. Among shoals of herrings and pilchards, flashes of light have been frequently observed to dart, so as to cast a sudden brilliancy across the whole; and oyster-shells, as well as a variety of minerals, have become phosphorescent at certain temperatures. These appearances have been attributed to electricity, which is rendered probable by various circumstances, and seems to be confirmed by the fact, that the electric shock causes substances of the kind last mentioned, to exhibit the same luminous appearance. However this may be, there can be no doubt, that the presence of the electric fluid is not unfrequently shown by the production of a harmless light, similar to that of the ignis fatuus. Sailors are not unacquainted with this phenomenon, which they regard with awe, and which is seen at night in the form of a star, illuminating the topmasts and yard-arms, or gliding along the ropes of ships. This light,the ancients superstitiously distinguished by the name of Castor and Pollux, considering it a lucky_omen. Mrs. Somerville mentions, that, in 1831, the French officers at Algiers were surprised to see brushes of light on the heads of their comrades, and at the points of their fingers, when they held up their hands.

One of the most striking appearances of this kind, which occurred at sea, is thus graphically described by the talented authoress above alluded to :

"Captain Bonnycastle, coming up the Gulf of St. Lawrence, on the 7th September, 1826, was roused by the mate of the vessel, in great alarm from an unusual appearance. It was a starlight night, when suddenly the sky became overcast, in the direction of the high land of Cornwallis county, and an instantaneous and intensely vivid light, resembling the Aurora, shot out of the hitherto gloomy and dark sea, on the lee-bow, which was so brilliant, that it lighted every thing distinctly, even to the

mast-head. The light spread over the whole sea, between the two shores; and the waves, which before nad been tranquil, now began to be agitated. Captain Bonnycastle describes the scene as that of a blazing sheet of awful and most brilliant light. A long and vivid line of light, superior in brightness to the parts of the sea not immediately near the vessel, showed the base of the high, frowning, and dark land, abreast. The sky became lowering, and more intensely obscure. Long tortuous lines of light showed immense numbers of very large fish, darting about, as if in consternation. The spritsail-yard and mizzen-boom were lighted by the reflection, as if gaslights had been burning directly below them; and, until just before daybreak, at four o'clock, the most minute objects were distinctly visible. Day broke very slowly, and the sun rose of a fiery and threatening aspect. Rain followed. Captain Bonnycastle caused a bucket of this fiery water to be drawn up: it was one mass of light, when stirred by the hand, and not in sparks, as usual, but in actual coruscations. A portion of the water preserved its luminosity for seven nights. On the third night, the scintillations of the sea reappeared; this evening, the sun went down very singularly, exhibiting in its descent a double sun; and, when only a few degrees high, its spherical figure changed into that of a long cylinder, which reached the horizon. In the night, the sea became nearly as luminous as before; but, on the fifth night, the appearance entirely ceased. Captain Bonnycastle does not think it proceeded from animalcula, but imagines it might be some compound of phosphorus, suddenly evolved, and dispersed over the surface of the sea; perhaps from the exuviæ or secretions of fish connected with the oceanic salts-muriate of soda, and sulphate of magnesia."*

Such, are some of the facts connected with what has been called phosphorescence. I shall make no attempt to theorize on the subject. When science is further advanced, it may probably be found, that phosphorescence,

* Connexion of the Physical Sciences,' 303, 304.

the ignis fatuus, and other innoxious illuminating substances, depend on some common property, which may serve to illustrate the mysterious subject of light and heat, and thus afford a further view of the laws by which the Creator regulates the material world.

SECOND WEEK-TUESDAY.

AURORA BOREALIS, OR NORTHERN LIGHTS.

THE Aurora Borealis is a phenomenon probably electrical, connected in some way with the magnetic poles, which sometimes beautifully illuminates our northern sky during the autumnal and winter months. Its use in the system of Nature has not been distinctly ascertained, though various conjectures have been formed. Dr. Halley supposed, that the earth was hollow, having within it a magnetical sphere, which corresponded in virtue with all the magnets on the surface; and that the aurora was the magnetic effluvia rendered by some means visible, and passing through or beyond the atmosphere from the north pole of the central magnet to that of the south. Boccaria adopts a similar idea, but attributes the phenomenon to the electric instead of the magnetic fluid, which, indeed, is now proved to be the same thing. The fallacy of this opinion has, however, been since shown by the fact, that the fluid, whatever it is, darts upward toward the zenith in the southern as well as in the northern hemisphere, whereas, were there a circulation such as has been conjectured, the course of the fluid would in the south have been reversed, descending from the zenith to the horizon. The supposition of Dr. Faraday, therefore, is, that the electric equilibrium of the earth is restored by the aurora conveying the electricity from the poles to the equator.

Without attempting to settle a point with regard to which sufficient data have not been collected, I shall

content myself with describing some of the remarkable appearances of this very curious and interesting phe

nomenon.

One circumstance worthy of notice has already been stated, namely, that the aurora bears some reference, not to the poles of the earth's rotation, but to what have been called the magnetic poles. It often forms a kind of stationary luminous arch, of which the magnetic pole is the centre, and across this arch the coruscations are rapid, sudden, and frequently of various colors. Its history is curious, no very distinct account having been recorded of its appearance in the classic ages of the world, though we do hear of strange signs in the sky which seem to refer to some celestial phenomena of a similar nature. [M. de Mairan, in a work on this subject, published in the year 1754, gives a table of all the recorded Auroræ from A. D. 583 to 1751; in which are numbered 1441 instances, 972 of which were observed in the winter half of the year, and 469 in the summer half.] Since the beginning of the eighteenth century, these appearances have been frequent but capricious, there being intervals of several years, during which they have been either intermitted altogether, or have been of such a nature as to attract little observation.

In the northern regions, the aurora appears with the greatest brilliancy; but it does not seem that the intenseness increases, as might be expected, in proportion to the nearness of approach to the magnetic pole. In the Shetland Islands, it cheers the winter nights almost constantly during clear weather. Its phenomena are there called the merry dancers, and are thus described; They commonly appear at twilight, near the horizon, of a dun color, approaching to yellow; sometimes continuing in that state for several hours, without any sensible motion; after which, they break out into streams of stronger light, spreading into columns, and altering slowly into ten thousand different shapes, varying their colors from all the tints of yellow to the obscurest russet. They often cover the whole hemisphere, and then make the most brilliant appearance. Their motions, at

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