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10th

19th :.

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The digits eclipsed are 6° 5' on the Moon's southern limb, or from the northern side of the earth's shadow.

Moon's Passage over the Meridian. The following transits of the Moon will afford opportunities for observation during this month, if the weather be favourable: viz. September 5th, at 14 m. after 5 in the afternoon

6th 5
7th 68
8th 54 7 in the evening
9th. 51
48

9
Ilth 46

10
12th 43 .11
18

5 in the morning
20th 11
21st

7
22d 52

7 23d 40

8 24th

9 PHENOMENA PLANETARUM.

Phases of Venus. The following is the proportion of the bright and dark phases of

this planet at the commencement of this month: viz. September 1st { Durminated part = 10:55897

1:44103 Eclipses of Jupiter's Satellites. Though there will be nearly thirty eclipses of the first and second of these satellites this month, only the two following will be visible.

Emersions. First Satellite ... 5th day, at 23 m. 6 s. after 7 in the evening Second Satellite, 26th

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6 Conjunction of the Moon with the Planets and Stars. September 4th, with y in Libra at 8 in the evening

10th B.. Capricorn... 1 in the morning
18th
18th .. 1&28, Taurus
18th
&... Taurus.

1 in the afternoon 27th B... Virgo 7 in the inorning.

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.. Taurus

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LUMINOUS ARCH.

[Seen September 29th, 1828.] Several accounts of this phenomenon have been given by observers at various places from five to nearly fifty miles from London; but the two following descriptions, from the Literary Gazette, will put our readers in possession of the principal circumstances respecting it. The first was written by J.T. B., of Deptford; the second, by Mr. Sturgeon, of Woolwich.

A very remarkable phenomenon, of the nature of Aurora Borealis, was witnessed on Monday evening last (Sept. 29th day, 8 hrs. 20 min.) A vast arch of silvery light appeared in the direction of the magnetic east and west, extending over nearly the whole of the heavens, and making with the western horizon an angle of about 70°, inclining to the south: the stars & and 8 Serpentarii were seen through its western extremity, from which the stream pursued its course between Lyra and Aquila, passing Cygnus, and after intersecting the Galaxy (which it considerably surpassed in brightness), proceeded through Andromeda to the Pleïades, where it terminated, describing in its course an uninterrupted luminous curve 1606 in length, its mean breadth about 3°, slightly expanding as it approached the magnetic east. A faint crepusculum, of a saffron hue, was observed in the magnetic north, but perfectly quiescent.

*8 hrs. 30 min.-The two stars in Serpentarius were occasionally obscured, or dimly seen through the extremity of the luminous arch, which, at that part nearest the horizon, seemed circular and well defined. At intervals these stars shone forth with undiminished brigbtness, forcibly suggesting the idea of the glowing nucleus of a comet, for which it was mistaken by many, who considered this unexpected appearance as the predicted messenger in its most tremendous form, suddenly arrived to execute its work of destruction.

'8 hrs. 45 min.-Until this time the splendid arch had continued stationary, with the exception of a diminution of its brilliancy in the north-east; there now, however, appeared in the north-west transient gleams of light, separating from the luminous stream in a lateral direction, the coruscations of which deter. mined the nature of the phenomenon.

68 hrs. 57 min.--A meteoric star rushed from the western part of the arch, and pursued a course towards the south: after traversing a space of about 10°, it suddenly disappeared.

9 hrs.-A narrow stratum of cloud intersected the stream at an altitude of 20°; shortly after this, the brilliancy gradually abated; and at 9 hrs. 30 min. the phenomenon had wholly disappeared. A brisk wind from the south-west prevailed during its appearance: the verge of the horizon was occupied by a low range of dense clouds.

The most remarkable circumstances attending this phenomenon were, its long quiescence, brilliancy, general equality of breadth, and uniformity of silvery semblance, not in the slightest degree resembling those red and brilliant hues which distinguished the aurora borealis of September 1827. It is to be regretted that there is not sufficient data for determining the height of this and similar phenomena: the calculations which have been made, vary from 150 miles to several thousands of miles : one observed in 1716 was seen under the same appearances in places very remote from each other, and ascertained to be visible from lat. 50° north all over the northern part of Europe, and from the confines of Poland and Russia in the East, to Ireland in the west, and most probably beyond these limits,-a sufficient confirmation of its very great altitude. The aurora borealis has been observed to be more frequent about the period of the equinoxes, and is considered by some as an unerring precursor of stormy weather: there is no doubt but that it is a magnetic phenomenon, the peculiarities of which are governed by the Earth's magnetism.'

Mr. Sturgeon observes—About a quarter before nine o'clock, when the light of the eastern limb began to be diffused, and exhibited lambent coruscations, with the assistance of Mr. Marsh, the electrical kite was raised in the Artillery Barrack-field: the wind blew briskly from about south-west, and three hundred yards of wired string were let off the reel. Strong sparks were obtained by presenting the knuckle to the reel, and a jar was frequently charged to a considerable intensity; but nothing particular, as regarded the electricity of the atmosphere, during a quarter of an hour that the kite was afloat, was by any means observed. I had, from my first observing the celestial phenomenon, expected to have seen a dense cloud (such as is generally observed to accompany the aurora borealis) in the horizon; but, until the arch had nearly reached the zenith, no such cloud was visible. About this time, however, the anticipated associate began to make its appearance, which for awhile could only be faintly traced by the eye, in the north part of the horizon. It soon became more dense, and better defined by a bright light round its upper edge; but no coruscations, although anxiously looked for, were ever observed to emanate from this part of the aurora.

Whatever general relation terrestrial magnetism has to the aurora borealis, I think it may fairly be in. ferred, that this particular display strikingly manifested their connexion. The plane of the curve, during the whole of the time, was unquestionably nearly (perhaps exactly) at right angles to the magnetic meridian.

Notwithstanding the atmosphere, during the display of the aurora, exhibited no unusual electrical phenomena, it certainly became more intensely charged during the following day than I bad ever observed it in the whole of the past summer. The kite was raised in the Artillery Barrack-grounds between twelve and one o'clock, and the same twine that was used the

preceding night was let out. On presenting the knuckle to the insulated wire, I experienced a tremendous shock, which affected my shoulders and legs, as if an immense battery of low intensity had been discharged from my hand to my feet. This unusual discharge suggested the propriety of immediately quitting the string. The insulating part was therefore tied to a tree, and there left, the kite floating about a hundred yards above the ground. Heavy clouds soon appeared to windward; but advantage was taken to lower the kite before they arrived over it. To prevent the effect of another discharge whilst running down the string, a loop was made at one end of a silk riband, through which the string passed, the other end of the riband being held in the hand. Notwithstanding this precaution, I received another blow much more formidable than the former. The discharge, in this case, passed over three-quarters of a yard of silk riband, from the kite-string to my hand; and as the silken insulation at the tree was not so long, it is likely that a considerable quantity of fluid was discharged from the end of the twine over the insulation to the tree. This discharge happened when about a hundred yards of the kite-string had become horizontal betwixt my hand and the tree; and what rendered it more extraordinary, no perceptible cloud was near the kite at the time. The kite, however, was soon brought to the ground without any other disagreeable effect. I never experienced any thing of the kind before, although I have had the kite afloat, with the same twine, more than a hundred times this year, under almost every circumstance of weather, and at various times of the day. The kite-string has uniformly exhibited positive electricity in every experiment.'

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