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DESCRIPTION OF THE AURORA BOREALIS.
coruscations were paler than the laminæ ob- first faded; the coruscations diminished served in the southern parts of the heavens : both in extent and number; the luminous they were, when first seen, about a degree in matter, that before extended over a considerbreadth, and they increased in height very able portion of the heavens, now settled rapidly. While these appearances were
down in the northern horizon; and about a taking place in the north, several laminæ quarter before seven nothing was left of this were succeeding each other in the south. beautiful phenomenon but a luminous apThe zenith as yet was clear; but the corus- pearance in the northern part of the heavens, cations in the north, though decreasing in that formed an arch, the highest part of breadth, were rapidly ascending to it, ac- which was in the direction of the magnetic companied with others from those parts that pole. were to the south of it, but from a region About this time a lamina appeared a litmore elevated than that in which the laminæ tle to the east of north, similar in appearance moved. Such was the rapidity with which to that observed across the constellation they were formed, and the laminæ them- Orion, with the exception of the extremities selves quickly vanishing, that the writer not being so well defined : this moved with could not ascertain whether those corusca- a moderate rapidity across the northern tions to the south of the zenith were given meridian, and about the same distance to out by the laminæ : but he would suggest the west disappeared. Nothing new in the that should laminæ again be observed of the appearance took place until half-past seven, description here given, the observers would with the exception of the arch of luminous do well to pay particular attention to them, matter gradually increasing in altitude, and and especially to notice any coruscations occasionally sending forth a coruscation or proceed from them.
two. At the time above-mentioned it had It was about six o'clock, when the scene, arrived at the zenith ; and the whole of the that the observer had been contemplating, northern hemisphere, bounded by a line arrived at its greatest splendour. The ex- drawn from a little to the north of east, and tremities of the arch above mentioned as- terminating a little to the south of west, had sumed a red appearance; the coruscations the appearance of an attenuated film or were exceedingly numerous both above and sheet of light, which was brightest in the below it, their breadth being very small; east and western extremities, and also in the and there was not a spot from the east to the north near the horizon. western point of the northern hemisphere Hitherto the meteor had been unattended that was not covered with them. The ap- with that shooting, or tremulous motion, pearance they presented was similar to the which has frequently been observed in other representation of falling rain; or they might phenomena of the same nature; and which fitly be compared to a numerous army with was very conspicuous in an Aurora ob. their weapons gleaming in the solar beams. served by the writer on the 12th of Decem.
They had now extended to the zenith, ber last. But an appearance now took place and met there, forming a most splendid similar to that observed in the Aurora of coloured corona. The colour of this part of March 6th, 1716, by Dr. Halley, and which the phenomenon was a lively crimson, or he termed nubeculæ. blood colour. The laminæ had now van- A thin luminous substance arose from the ished, but a considerable quantity of lumin- east and western extremities of the arch, perous matter was seen extending to the south pendicular to the horizon; and passed along from the west; the south-eastern being the the heavens towards the zenith with great only portion of the heavens, that did not at rapidity. Its duration was momentary; for this time display some of the varied forms it was no sooner formed, than it vanished. of this meteor: this part, however, had not This appearance was repeated incessantly been exempt, as several laminæ had previ- for the space of nearly half an hour; during ously traversed it, which occasioned the which time the luminous matter of the observer to think, that the luminous matter, northern hemisphere had extended beyond which was seen near the south, would the zenith towards the south; and several quickly pass the planet Mars, then near the lucid portions which were constantly formed, meridian, and thus succeed them. But this as rapidly disappeared in the southern porwas not the case, for the phenomenon hav- tion of the heavens. ing arrived at a degree of splendour, an ade- A most interesting part of the phenoquate idea of which it is impossible for menon now began to present itself. The language to convey, began now to decline, meteor nearly occupied every portion of the as if it had spent all its strength in producing heavens, and the brilliant extremities of the the splendid spectacle that the writer wit- arch above-mentioned, especially the eastern, nessed. The coloured corona in the zenith began to throw out, or rather separate, into long and thin coruscations, similar to those darting from the east and western points of observed previous to the formation of the the horizon towards the zenith, but not to corona before alluded to. These were soon the extent and variety they were before obattended with a separation of the luminous served. At a little past ten, the eastern matter in the northern hemisphere into extremity of the arch began to show signs coruscations of the same nature. This ap- of again separating into coruscations ; but pearance was noticed a little after eight, the substance shortly united, and thus conwhen those portions of the heavens, which tinued until half-past ten, when some clouds before were the most luminous, presented a arose from the north-west point of the hocoloured appearance.
rizon. At eleven the eastern extremity of The writer noticed three distinct portions the arch assumed a copper-coloured hue, of coloured coruscations : one in the direc. which gradually became a pink, and extion of the magnetic meridian, and one on tended to the zenith. A few coruscations each side, at the east and western extremi- now shot from the horizon near the east; but ties of the arch, which, at this time, was lost the meteor was evidently decreasing; and in the multitude of coruscations that now the clouds at this time overspreading it, put presented themselves to the sight of the ad- an end to further observations. miring spectator. The coloured portions Having endeavoured as accurately as poswere not contiguous throughout the whole sible to describe the various appearances he length of the coruscations, but arose only to saw, the observer will proceed to classify a determinate height above the horizon; them, in order to facilitate the comparison their breadth being nearly equal to their of them with others of the same nature. The length. The summits of the coruscations Aurora above described may naturally be were white, and they now met at some dis- resolved into three distinct parts: the first, tance to the south of the zenith, where they comprising the appearances previous to the formed a second corona. This magnificent formation of the coloured corona : the seappearance continued about a quarter of an cond, the space of time occupied between hour, when the corona and coruscations, the two coronæ : and, the third, the phenowith their superb colours, gradually became mena presented after the disappearance of fainter, and, at last, were lost to view. the second corona.
About a quarter before nine, a new phe- In considering the first portion, there are nomenon presented itself. The luminous four objects that present themselves to our matter had again settled down towards the notice. The luminous arch, and the corusnorthern horizon; but instead of forming an cations observed in the north; the laminæ arch, as on the former occasion, it assumed in the south, and the coloured corona in the the appearance of a bright streak, or lamina, zenith. Of these the arch claims considerawhich had a serpentine form; the eastern ble attention; as it shows the manner in part being more elevated than the western : which the luminous matter has a tendency it was also remarked, that the eastern ex- to arrange itself. tremity was curved towards the horizon. As all Auids, when isolated, form a sphere This appearance gradually assumed the or globe, so the luminous matter of the arched form, which was again complete at Aurora appears to have arranged itself in a half-past nine, when it had a considerable form something allied to this, although there elevation. The luminous matter had also are circumstances that prevent its taking a arrived at the zenith; but the appearance globular shape. It is also probable, that now was different to that noticed, as the the luminous matter observed in the Aurora, luminous arch approached the zenith be- to be contiguous to the northern horizon, was tween the formation of the two coronæ. The vertical to some portion of the earth's surwhole of the northern portion of the heavens face. If so, we may inquire, what would be was then overspread with nearly an uniform the appearance at that spot? It is evident, sheet of luminous matter; a line drawn from the luminous matter would be seen in the the zenith to the east and west points of the zenith, spreading therefrom in every direchorizon (nearly) forming the southern boun- tion towards the horizon. Therefore, if the dary thereof.
luminous matter takes a circular form (which At the present time, the luminous sub. is very probable) at those portions of the stance appeared to be divided into two earth's surface considerably removed from portions : one bounded by the arch, which the central part thereof, it would assume was considerably the brightest; and the the form of an arch ; the heights of which, other extending to the zenith, which ap- above the horizon, would depend partly on peared rather faint and diluted, compared the extent of the luminous matter, and with the former observation. It was about partly on the distance from the central ten o'clock when nubeculæ were again seen point. This hypothesis may, probably, be
DESCRIPTION OF THE AURORA BOREALIS.
confirmed ; if, on future occasions, observers pearance of the arch, extending gradually to are diligent to notice the appearances pre- the zenith. The luminous matter at this sented to them, and, as Dr. Halley directs, time was evidently extended over a very in his account of the Aurora of 1716, set considerable portion of the earth's surface; their clocks to apparent time, and note and the boundary now passing over the place especially the altitudes and azimuths of of observation, gave an opportunity of noevery remarkable portion of the pheno- ticing the manner in which the additions to
the arch were perforined, viz. by the action The coruscations are the next objects that of the nubeculæ; for as these phenomena demand our attention: these may in the were darting across the heavens, the luminpresent example be divided into two kinds, ous matter was increasing in size; and as it viz. those that were observed to shoot from approached the south, the nubeculæ were the horizon, and those that resulted from a noticed still more southerly. From this it separation of the luminous matter. The appears, that the luminous matter, when first coruscations that shot from the horizon ap- generated, assumed the form of nubeculæ, peared to the writer to consist of the same which darted with considerable velocity luminous matter as the arch, but under a around the circumference of condensed different form, and those that resulted from luminous matter that formed the arch. a separation of the luminous matter, were The substance that gave birth to these evidently composed thereof. The laminæ nubeculæ, although seen under that form in the south appeared to consist of detached but for an instant, was, probably, attracted portions of the same luminous matter, that by the matter composing the arch, with was generated in the regions in which they which it united ; and upon its becoming were observed. Their situation, with respect more condensed, appeared to increase that to the earth's surface, may easily be ascer- portion of the meteor. The lucid portions tained, if their altitudes have been observed in the southern parts of the heavens appeared at various places, especially to the south of to be of the same nature as the nubeculæ ; this.
but in consequence of their distance from Their motion from west to east is an in- the central mass, they continued to be seteresting feature, and demands the attention parated therefrom. When the operation of of every philosophic observer, especially as the nubeculæ ceased, the separation of it is the direction in which the heavenly the luminous
into coruscations bodies perform their revolutions. The co- began to take place : there was, therefore, loured corona appeared to be formed from at this period of the phenomenon, an union of the coruscations in the zenith; evident change. A very considerably quantity and when the meteor had arrived at this of luminous matter had collected together, stage, the coloured appearances were pro- which, in three distinct parts, was considerduced.
ably condensed. There appeared now no The writer having briefly considered the more luminous matter to augment the arch; first part of the phenomenon, will proceed and, when it attained a certain extent and to enumerate the objects presented in the intensity, an internal motion appeared to second. These are, a similar luminous arch; take place in the meteor, by which the the nubeculæ that darted from the east and luminous matter was separated into filaments, western portions of the horizon towards the of which the coruscations were forined. zenith; the separation of the luminous mat. It was remarked, that these coruscations, ter into coruscations; and the formation of a as well as those observed in the former part second corona, attended with the colouring of the phenomenon, were not contiguous of the coruscations. It was this portion of throughout their length, but appeared broken the Aurora that particularly interested the in several places. It was the union of their observer; for here he had an opportunity of extremities in a point, situated on the bountracing the formation of this brilliant specta- dary of the luminous matter, that occasioned cle, and observing the growth thereof imme- the appearance of the corona: and it must diately under his eye.
be remarked, that both the coronæ were After the superb corona, and brilliant seen in the direction of the meridian. Their coruscations of the former part, had vanished, formation will illustrate the manner in which nothing was presented to the view, but a the separation of the luminous matter into small portion of luminous matter, which had coruscations was efíected. This appeared again arranged itself in the form of an arch, to be twofold; one in a direction diverging This apparent focus of the phenomenon, in from the centre; and one, by which the consequence of receiving fresh supplies of filaments were arranged in concentric lines. puminous matter, was continually increased By the separation first taking place in the in size; and thus was occasioned the ap- extremities of the arch, it appears, that 2D. SERIES, NO. 3.--VOL. I.
portions which were the most luminous, and, the world with Captain Cook, describes a consequently, the most condensed, were first similar phenomenon observed towards the resolved into filaments; the direction being South Pole. The London Encyclopedia conconcentric of those near the circumference, tains an interesting article on this meteor, in and divergent of those near the centre of the which M. Libes theory of its production luminous matter. Those that were differently merits attention. And the Quarterly Journal situated appeared to follow a direction be- of Science, part 2, 1827, page 385, contains tween the two just mentioned.
a most interesting paper on the Aurora of Now, the union of these differently directed the 25th of September, 1827, by E. A. coruscations would occasion the appearance Kendall, Esq. F.S.A. of the coronæ. These would appear in or
The writer will only add, that the present near the zenith, according as the boundary is the fifth Aurora that he has observed since of the luminous matter passed over or near the beginning of September last ; and he has thereto, and would also be noticed in the also been informed, that there have been direction of the meridian, if the centre of four besides, which he did not see. One, the luminous matter coincided therewith. It that he observed on the 12th of December, was at this stage of the phenomenon that was very considerable; but having had his the coruscations became coloured; from attention directed to it only for a short time, which it appears, that the colours really he is unable to give that accurate description belonged to the luminous matter, and were of it which he could wish. It was, however, not dependent on that atmospherical medium attended with a very distinct arch, of consithrough which it was seen : for it may be re
derable elevation. The coruscations were marked in the present Aurora, that no por- powerful, and had an altitude of about 70°. tion of it assumed a coloured appearance The observer noticed on this occasion a until the luminous matter was resolved into quick, tremulous, or flashing motion in the coruscations; and shortly after this display luminous matter composing the arch; first of colour took place, in both instances, the on one side, and then on the other. These substance of which the Aurora was com- appearances arose from the lower parts of posed subsided.
the arch, and ascended to its boundary. The In the third part of the phenomenon, extremities of the arch became tinged with there is only one particular different from a copper colour, during the time the writer what has been before noticed, viz. the was observing it : and after this took place, curved lamina observed in the north, after he noticed that the phenomenon decreased. the disappearance of the corona and corus- It may be remarked, that the breadth of the cations. This, most probably, arose from coruscations in the Aurora just mentioned those portions of the luminous matter that, was much greater than of those in the pheprevious to the formation of the corona, were nomenon above described ; and that the more condensed than others. Upon the latter was unattended with the tremulous subsiding of the luminous matter, these con
motion of the former. densed portions would prevent its taking that regular form which it otherwise would have done, and which it ultimately did, in
VIGIAS, OR ROCKS, IN THE ATLANTIC. the formation of another arch. The cir. ANOTHER of these thorns in the sides of cumstance of there being a distinction be- navigators is said to have sprung up in the tween the arch and the luminous matter Atlantic, but fortunately, on authority which, showed, that the phenomenon, in the third although founded on ocular demonstration, stage, was not near so active as in the two is not sufficient to overcome our scepticism former.
as to its reality. In closing these remarks, the writer will The master of a ship and his mate, on refer the reader to several accounts of this their way to the island of Ascension, from interesting meteor, that have been published, England, say they saw a rock in lat. 6° 0 which will materially assist him in his S. and lon. 12° 57' W. Now, we are not researches into the natural history thereof. for adding another to the long list of these
In the Philosophical Transactions, No.347, “said to be" rocks, to create uneasiness to page 406, he will find an account of the our seamen, nor are we for altogether adoptbrilliant Aurora of March 6th, 1716, ob- ing so bold a course as to pay no attention served and described by Dr. Halley, who to them, but we decide according to cirhas suggested some ideas as to the cause cumstances. The position, however, assigned thereof. Nos. 351 and 352, of the same to this has been so often traversed by ships of Transactions, contain accounts of Auroræ all nations, that, had such a rock existed, it observed by Mr. Barrel and Mr. Foulkes. must have been known long ago; nay, Forster, in the account of his voyage round almost from the time of the Portuguese
A PERUVIAN DINNER PARTY.
voyages along the coast of Africa, in search children of old domestics, clean and tidy; of Cabo Tormentoso. There are few well- an Indian boy, as may be sometimes seen authenticated vigias, of the many said to in another “land of potatoes,” shirtless, exist; and if all were marked on the charts, shoeless, and stockingless; a very fine the commander of a ship would scarcely negress slave, and an elderly woman, evi. venture to sea.
dently the confidential servant, were the The reality of Aitkin's rock on the north attendants. For nearly an hour, immense coast of Ireland, bad never been doubted silver dishes were carried in and carried until its existence was proved to be impos- out, with the various compositions of our sible by the vessels sent to look for it last repast. The first course consisted, as is summer; and when the authority on which usual in the country, of cheese and fruit, it is laid down in the charts is investigated such as melons, apples, figs, chyrimoyes, by a seaman, it turns out to be vague and lunas, membrillos, &c. Then came two or indeterminate.
three kinds of soup or porridge, with rice The Devil's rock in the middle of the en- prepared in different ways. After these trance to the bay of Biscay is not yet found, were removed, there was no regularity obalthough a ship has been sent to look for it. served in the courses; for, whilst some of The sand-bank between Bermuda and the attendants carried off the dishes that had Halifax has been stated to exist, but on been helped from, or, if not yet touched by very doubtfuļ authority : yet there is no us, that had remained long enough upon doubt that a very dangerous rock, about a the table to gratify our view, others were at hundred miles to the westward of Bermuda, hand instantly to replace them : there was does exist.
no opportunity given to remark, that
Each dish contained sufficient for a party (From Temple's Travels in Peru.) of twice our number; and from every one I AVAILED myself this day of a general I observed Donna Juliana take a large invitation to dinner, given with un- plateful, sometimes two platefuls, and, sayfeigned cordiality by Donna Juliana Inda- ing something in Quichua, hand them to lesias, the rich widow of a man who, before one of her Indians, who placed them in a the revolution, was one of the first among distant corner of the room. When the the many wealthy merchants then esiding more substantial subjects of the feast were in Potosi. Donna Juliana never omits discussed, then followed custards, and comdaily attendance at mass, nor absents herself potes, and sweetmeats, from which small from any procession or particular ceremony portions were also taken, to be husbanded, of her church, and would consider it a as I imagined, for to-morrow's fare. А crime to conceal her veneration for the dish of very good potatoes, accompanied images and paintings of saints which hallow with very bad butter, concluded the dinner. and adorn her apartments. She also highly When the cloth was removed, all the respects, and distinguishes from all her attendants, without any word of command, other friends, those whose peculiar calling ranged themselves in a rank in the middle it is to instruct mankind in the sacred doc- of the room, and, suddenly dropping on trines of religion, seldom sitting down to their knees, sung, or said aloud, a grace dinner unaccompanied by a priest or friar, that lasted full four minutes, in which the who have free admission to her plentiful deep-toned voices of Padre Costas and table. That, however, which may excite Friar Francisco, nothing mellowed by their surprise, because so seldom in accordance hearty meal, and ample goblet of Cinty with ostentatious acts of devotion, is the wine from the estate of our hostess, chimed fact, that she possesses the kindest heart in in like bass-viols, whilst Donna Juliana, the world, and dispenses charity with true pressing her cross and beads to her bosom, benevolence. She is known by the appel- her eyes devoutly fixed upon a beautiful lation of “ La buena Cristiana,” and never painting upon the Virgin and Child, which was distinction more deservedly bestowed. hung opposite to her, in a large massive
Donna Juliana, Cura Costas, (the re- silver frame, accompanied the others in all spectable head of the church at Potosi,) the fervency of thanksgiving. Padre Francisco, (a Dominican friar, whose “ Amen !” with the sign of the cross, as a portly corporation excited in my mind a benediction upon the company, by Padre malicious suspicion of his being more Costas, ended this appropriate ceremony, accustomed to feasting than fasting,) were in the solemnity of which the most obduthe party with whom, at two o'clock, I sat rate heretic could not have refrained from down to dinner. Three Indian girls, the joining.