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THE AURORA BOREALIS. The Aurora Borealis is a lumi. frequently covering the whole ate nous appearance, generally observed mosphere, exhibiting the most roin high northern latitudes, and com- mantic forms and the most beauti. monly to the north of the observer, ful appearance. According to Muschwhence it has got the name of North- enbroek, in that region of the air ern Lights; it known also among which is directly towards the north, the vulgar, by the name of “the or which stretches from the north streamers,” or the “ merry-dancers.” towards the east or west, there at first
The Aurora Borealis may be di- appears a cloud in the horizon, which vided into two kinds, the tranquil rarely rises to the heightof 40 degrees. and the varying. The tranquil shines This cloud is sometimes contiguous with a mild and steady light, similar to the horizon, sometimes detached to the different stages of moon-light, froin it, in which last case the ineither as it appears near the time of termediate sky appears of a bright new moon, or as it gradually in- blue colour. The cloud occupies a ereases when the moon becomes more portion of the heavens, extending in enlightened ; sometimes it is more length to 100 degrees, and somevivid than the light of the moon times still farther. It is generally when full ; and it often preserves, white and shining, but sometimes for a considerable time, the form in black and thick. Its upper edge which it first appeared, with little or is parallel to the horizon, bordered no variation. Muschenbroek has paid by a long train of light, which rises much attention to this kind of me- higher in some places than in others. teor, and has given it several names, It appears also bent in the form of a according to the form which it as- bow, or like the segment of a sphere sumes; butas these names are founded which has its centre considerably only in fancy, and are not necessary beneath the horizon ; and sometimes to an explication of the theory, we a large white or luminous band is shall omit them. The varied Au- visible, skirting the upper edge of rora is more remarkable in its ap- the black cloud. The dark part of pearance, and occasionally exhibits the cloud becomes white and lumithe most brilliant and rapidly diver- nous when the Aurora has shone sified forms. The following are some for some time, and after it has sent of its very interesting properties: It forth several bright and fiery rays.' is usually of a reddish colour, in. Then, from the superior edge of the clining to yellow, and it frequently cloud, rays issue in the form of jets, sends out corruscations of pale light, which are sometimes many, somewhich seem to rise from the horizon times few in number,--sometimes in pyramidal undulating forms, shoot- close together, sometimes removed ing with great velocity towards the several degrees asunder. These jets zenith. TI kind of meteor, which diffuse a very brilliant light, as if a is less frequent as we go towards the luminous or fiery liquor were driven Equator, is almost constant during with impetuosity from a syringe, the long winter nights in the Polar The jet increases in brightness, and Regions. In the Shetland Isles they has less bulk when it at first issues afford the inhabitants great relief, from the cloud ; but it dilates and amid the gloomy darkness of their grows dimmer as it goes farther off. long and dreary nights. They com- There then arises, from a large openmonly appear at twilight, near the ing in the cloud, a luminous train, horizon, of a dun colour, approach- or column, of which the motion is at ing to yellow, and continue in that first gentle and uniform, and which state for several hours ; they aftere increases in size as it advances. The wards break into streams of stronger dimensions and duration of these light, spread into columns, then columns vary considerably ; their slowly alter into innumerable shapes, light is sometimes white, sometimes and vary their colours from all the reddish, sometimes of a blood colour ; yellow tints to an obscure russet; and as they advance, their colours
change, till they form a kind of arch assumed all the tints of violet and in the heavens. When several of blue, it formed a dome, the summit these columns, issuing from different of which was near the zenith in the places, encounter each other in the south-west. Its splendour was so zenith, they intermingle with each great as not to be affected by the other, and form, at their junction, a strong light of the moon.
He adds, small thick cloud, which seems, as it that he only observed two of these were, to kindle, and sends forth a red northern lights while he was in light considerably more brilliant Lapland, and thinks that they are than any of the separate columns. of rare occurrence in that country, This light changes to green, blue, although the Aurora there assumes and purple; and, quitting its origi- a great variety of tints; he moreover nal station, it directs itself towards observes, that they are considered the south, in the form of a small by the poor ignorant natives as omi. bright cloud. When no more co- nous, and the forerunners of calalumns are seen to issue, the cloud mity. assumes the appearance of the morn- The accounts of noises attending ing dawn, and insensibly dissipates the Aurora Borealis are sufficiently itself. Sometimes the Aurora is corroborated; they have been heard formed and disappears in the course by numerous persons, and in various of a few minutes ; at other times places. They have been heard in it continues the whole night ; and Hudson's Bay, in Sweden, Norway, one that was observed by Muschen- and Lapland. Muschenbroek menbroek in 1734, lasted for ten days tions, that the Greenland whale-fishand nights successively. The lucid ers assured him that they had frecolumns are often so transparent, quently heard the noise of the Authat stars of the first and second rora; but he adds, that no person in magnitudes are visible through them; Holland ever heard any noise occathese also shine through the white sioned by them. Mr Cavallo, howborder of the horizontal cloud, and ever, declares, that being in Northsometimes, though rarely, through ampton at the time when the northern the opaque cloud itself. But many lights were remarkably bright, he is parts are so thin, that the smallest confident that he heard a hissing or stars which are visible to the naked & whizzing sound. In the Orkney eye may be seen through them. A and Shetland Isles they are frequentmore beautiful spectacle than what ly heard. The writer of this article is very frequently presented to us has been told by more than one in these meteoric appearances, can- gentleman from Orkney, that the not easily be imagined ; the specta- noise made by the Aurora is often cle is often grand and terrific, and is heard by the natives; and one of sometimes attended with a hissing, them assured him that he had somecrackling noise, which rushes through times heard it himself. They have the air, and is similar to a display of also been heard in Canada. As we large fire-works. The hunters who might very naturally expect, the pursue the white and blue foxes, Aurora Borealis is by no means conon the confines of the icy sea, are fined to the northern hemisphere ; often overtaken by these northern for similar appearances, and like lights, at which times their dogs are noises, have been observed and heard so much frightened that they will in high southern latitudes. If the not move, but crouch upon the existence of the Aurora Australis was ground till the noise has passed by at any time doubtful, it was comthem. Maupertuis observed a re- pletely ascertained by Captain Cooke markable Aurora at Oswer-Zornca, in his second voyage round the world. which excited his admiration ; an “ On February the 17th, in 1773,” extensive region of the hçavens to- says Mr Foster, who accompanied wards the south appeared tinged Cooke in the capacity of Naturalist, with so lively a red, that the whole “ in south latitude 58 degrees, a of the constellation Orion secmed to beautiful phenomenon was observed be dyed in blood. This light was for during the preceding night, which some time fixed, but it was soon in appeared again on this and several motion, and after having successively following nights. It consisted of
long columns of a clear white light, 40 degrees high, of a pale yellowish shooting up from the horizon to the colour, and sent out, on one side, a eastward, almost to the zenith, and process which approached the S. E. gradually spreading over the whole by E. point of the horizon, and on the southern part of the sky. These other was connected with a long recolumns were sometimes bent side- gular arch, terminated in the N. W. ways at their upper extremities; and horizon, similarly constructed, and though in most respects similar to having the same waving motion with the northern lights of our hemis the curtain itself. All this time the phere, yet differed from them in be- sky was perfectly clear, except in ing always of a whiteish colour; the southern quarter, which, to the whereas ours assume various tints, height of 4 or 5 degrees, was occupied especially those of a fiery and purple by dark clouds, apparently intermehue. The sky was generally clear diate between stratus and cirrostrawhen they appeared, and the air tus.” Several theories have been sharp and cold, the thermometer proposed in order to explain the nåstanding at the freezing point." ture of this meteoric appearance ;
The most complete series of obser- but none of those which have yet vations on the Aurora that has yet been published are satisfactory. The been published, is given by Dr Riche following account and explanation of ardson, in “ Franklin's Journey to the theory, which were communicathe Shores of the Polar Sea." We ted to me by Dr T. S. Traill of Liextract the following: “ I have verpool, are conclusive ;-the theory never heard any sound that could be agrees entirely with the phenomena, unequivocally considered as origina- and leaves, I think, little more to be ting in the Aurora ; but the uniform desired on this subject : * The extestimony of the natives, both Crees, tent of the Aurora in the Orkneys Copper Indians, and Esquimaux, I never accurately ascertained, but and of all the older residents in the I have occasionally observed it to country, induce me to believe that cover more than two-thirds of the its motions are sometimes audible. canopy of heaven. I once saw an These circumstances are, however, Aurora of a uniform blue colour slowrare, as will appear when Í state, that ly rolling from the northern quarter I have now had an opportunity of of a cloudless sky, and extending even observing that meteor for upwards of beyond the zenith ; occasionally its two hundred different nights." The volume expanded so as to involve alAurora, of which the following is a most the whole heavens, presenting description, must have been exceed the magnificent spectacle of a vast ingly beautiful : " When the Au, dome of lambent Hame with a cire rora had exhibited itself in this form cular aperture in the centre. for a considerable space of time, the “ The most usual periods for the whole mass of light suddenly appear occurrence of the Aurora in Orkney ed in motion, and sweeping round on are about the end of autumn, and the each side, was gathered together to end of winter; but it occasionally octhe southward of the zenith. Im
curs at every season of the year, mediately after, a large portion of it though it is, in general, mos was seen in the S. E., assuming an in the absence of moonlight. Some exact resemblance to a curtain suse philosophers have mentioned, that pended in a circular form in the air, they have heard a peculiar kind of and hanging perpendicular to the noise, like the rushing of air, or the earth's surface. The lower edge of rustling of silk, during the appearthis curtain was very luminous, and ance of the Aurora Borealis ; this is had a waving motion ; and the illu a circumstance, the truth of which I sion was farther heightened by the am able to confirm by repeated obmomentary appearance of perpendi- servations. I am quite certain that cular dark lines, or breaks in the I have heard this rustling noise, light, in rapid succession round the which was once particularly distinct circle, exactly as the waving of a cur as I stood alone, at midnight, on the tain would cause the dark shades of top of a lofty tower, when every thing its folds to move along it. This was still around. The real height beautiful curtain of light was about at which this meteor occurs has never
yet been ascertained. In 1716, 1726, from comparing the Aurora Borealis and 1729, the Aurora Borealis was as it appears in our high northern latiobserved in every part of Europe; tudes, with the appearance of the Aubut we do not know that it was the rora Australis as it appears in much very same Aurora which was observe lower southern latitudes. Some phied at distant places, else we could losophers have ascribed the Aurora to ascertain its elevation in the sky. At the inflammation of hydrogen gas in any rate, the Aurora is a meteor which the upper regions of the atmosphere. must be very high in the atmosphere, There is considerable reason to supfrom the distance at which we know pose, that while various processes are one has been visible. It cannot, how- going on at the surface of our earth, ever, be higher than the upper limit and particularly during the action of of the atmosphere, which does not evaporation, that some water is deexceed 70 or 80 miles ; and it is ex- composed. If this process really goes tremely probable that no Aurora has on, it must be allowed that the hyever been observed at an altitude drogen thus liberated, being much greater than 45 miles; and, there- lighter than air, would rise to the fore, it follows, that the immense top of the atmosphere, and, after heights given to this meteor, from rolling down the inclined planes observations made by Mairan, and formed by its upper surface, would others, were obtained from false data. accumulate near the poles. If the Mairan (at page 74 Traité Physique electric fuid pass through this hy; Historique de l'Aurore Boreale") has drogen, it may set it on fire, and determined the height of an Aurora thus produce the Aurora. This hyto be 200 leagues, which is evidente pothesis is, perhaps, the most plausily false ; but we are to consider that ble that has yet been advanced, to he had a particular object in view account for this extraordinary mehe had formed the strange notion teor. The successive ignition of the that the Aurora, as well as the zodi. portions of hydrogen, as they come in acal lights, are both produced by the contact with the oxygen of the air, solar atmosphere. The supposition are supposed to occasion the corruscahas, however, been completely re tions of the Aurora; and the small futed by Laplace: for this illustri- quantity of oxygen present in such ous philosopher has proved, that the rare air accounts for the duration of sun's atmosphere cannot extend to the combustion. Granting that this the orbit of Mars, much less then hypothesis is correct, there should can it extend itself as far as the be a vacuum formed towards the orbit of the earth ; and, consequent- pole by the condensation of the gases, ly, it can never be the cause of the and an Aurora in our hemisphere Aurora. It is evident that the Aurora ought generally to be followed by a cannot be above the earth's atmose southerly wind. Now, Mr Wynne, phere, because, as it apparently re- in the Philosophical Transactions of mains stationary for several hours, it the Royal Society of London, inmust partake of the common motion forms us, that in twenty-three cases both of the earth and the atmosphere. which he observed, an Aurora was, This meteor increases in brilliancy as without exception, followed by a we advance towards the north ; and, southerly wind. When the Aurora for nearly half the year, it supplies was very brilliant, the south wind the absence of the sun to the shi. on with considerable force vering tenant of the frigid zone.' within twenty-four hours; when For a long time the northern lights the Aurora was faint, the wind were supposed to be peculiar to the was longer in coming on, was weaker northern hemisphere, but the voy- also, but continued longer. In the ages of discovery in the southern Orkney and Shetland Isles, where ocean, and the increasing intercourse the Aurora is usually much more between the northern and southern brilliant than I recollect ever to have hemispheres, have shown that they seen it in any other part of Britain, prevail also towards the south pole. it is usually reckoned to be the foreThe Aurora Australis has been de. runner of a gale ; and I have obscribed as paler than the Aurora Bore. served, after a vivid appearance there, alis; but, in all probability, this arises in several instances, that it was soon
followed by a strong gale from the dently caused by the frequent dissouth, or from the south south-west. turbance in the motion of the needle According to the account given in which the Aurora occasioned; for • Franklin's Journey to the Shores of on those days when it was not visible, the Polar Seas,' it is evident that, at the mean diurnal variation followed the time of an Aurora, electro-mag. the course Mr Hood had observed it netism is produced; for, at the time of to do at Cumberland House, being the appearance of an Aurora, the mo- most easterly at the time of the first tion of the magnetic needle was dise observation in the morning, and least turbed; and this circumstance is between three and four in the afterquite agreeable to the above hypo- noon. The change in the diurnal thesis. Franklin says,' the appeare variation in these parts of North ance of the Aurora, and the disturbo America seems to be governed by ance it occasioned on the motion of the same law as in England, as the the needle at Fort Enterprise, were decrease in easterly variation between so frequent, that the mean monthly the morning and afternoon is, in fact, variation must have been deduced a motion of the needle to the westfrom but few observations if they ward.” had been rejected. And again, For much more interesting infor
the circumstance of the mean va- mation on the same subject, we reriation being least at midnight there, fer to the volume above quoted, and and at Moose-Deer Island, was evie from which these are extracts.
WWoman's Love. THERE'S wassail in Lord Walter's hall, Full many a cheek grew pale beneath And smoking beeves and red-wine That bugle's wild and thrilling sound, flowing ;
For it seem'd the blast of one whom Merry are the hearts of his kinsmen all,
death And the dames' dark eyes are gladly Long since in foreign land had found. glowing;
But Walter started with a shriek While, lower ranged, his vassal train
“ He comes ! he comes! the grave
hath giv'n Devoutly quaff the foaming ale, Or with the blade, ne'er drawn in vain,
Him forth his guilty prey to seek, The sirloin's mighty mass assail :
To mark how poorly guilt hath
thriv'n.” The harp is sounding proudly too, While chaunts the minstrel old and
Out flew bright blades from many a thigh, hoary,
The coming horror to destroy,– From Norman spears how Saxons flew
While ladies crept their lovers nigh, On Hastings' day of deathless glory.
Jesu ! 'tis but a tiny boy! And yet by friends though girded round,
His locks were of as dark a dye Though lovely lips and eyes are near
As ever rob'd the raven's wing ; him,
And his eyes shone out like the stars on Though lands, herds, flocks, and gold a.
When forth in gloaming hour they And kinsmen love and foemen fear
He tripp'd to where Lord Walter stood, Lord Walter mute and sadly sits,
And in a soft and witching tone, As were nor guest nor kinsman near;
Which every angry thought subducd, And as his eye is rais'd by fits,
Thus the dark-eyed youth went on :It wears the hurried glance of fear. 66 It was a Knight, an English Knight, Pale lips, and eyes deep sunken, shew
Bound was he for Paynim fight; Passion hath wrought the work of time;
And with an hundred in his train, But is it pure and blameless woe,
With Norman ROBERT cross'd the main. Or sleepless, dire remorse for crime ?
His brother, young Lord Henry, too,
With him his maiden faulcheon drew, While thus he mused, casting a shade And many a feat of fame they shar’d, Of sorrow upon every face,
Many a deed of danger dar'd, It chanced a distant bugle bray'd
Till, at the length, this elder Knight A note that peal'd through all the place. Captive was made in unequal fight.