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In November, 1830.
“ The Sun
The Sun enters Sagittarius at 37 m. after 6 on the 22d of this month.
Table of the Sun's Rising and Setting for every
6th, ........ 20 ...... 7, .. 40 .....
21st, ........ 45 ......
Equation of Time. To find the mean or true time from that indicated by a good sun-dial, subtract the following quantities from apparent time, viz. TABLE.
m. s. Monday, Nov. 1st, from the time by the dial subtract 16 15 Saturday, 6th,...
........ 16 12 Thursday, 11th, ....
........ 15 49 Tuesday, - 16th,..
........ 15 4 Sunday, - 21st, ...............
...... 13 58 Friday, 26th, ...
Phases of the Moon.
Moon's Passage over the Meridian. The Moon will pass the meridian at the following convenient times for observation, viz:
Nov. 5th, at 20 m. after 4 in the morning.
8th, 9th, 10th, 11th, 21st,
4 in the afternoon.
7 in the evening.
26th, .. 4
Phases of Denus. The planet Venus will this month pass from Virgo, through Libra, into Scorpio, but too near the Sun for satisfactory observation. The following are its proportional phases : Nov. 1st. Illuminated part = 11.740
Dark part ..... = 0.260
25th, .. Mars ........ 12 noon.
THE ENCKE COMET.
Towards the latter end of the year 1828, the public mind was much occupied by many strange accounts of the appearance of comets; the planet Venus then shining brightly as a morning star, was mistaken for one; the nebula in Andromeda, which is indistinctly seen by the naked eye, was repeatedly pointed out as another; and “ the luminous arch” referred to in the last volume of Time's Telescope, was by several considered to be the train of a retreating comet.
This feeling, it is highly probable, originated in the uncommon interest that had been excited by the anticipation of the return of “.the comet of Encke,” which was then anxiously looked for from every observatory in Europe; the interest evinced in the present instance was considerably increased, its course in the heavens being peculiarly favourable
for observation in the northern hemisphere; it was seen from several of the observatories on the continent, early in October, but not satisfactorily from the British Isles till the middle of November. When first observed, it was near the head of Cassiopeia ; by the end of October it had passed through the Square of Pegasus, and was advancing towards Delphinus and Aquila, near which was its situation on the 21st of December ; it soon after became invisible from its proximity to the evening twilight.
The following description of its appearance as seen from Deptford, is from the “Literary Gazette."
6. The comet, concerning which so much interest was excited some time since, having re-appeared, as predicted by Professor Encke, and pursued its course in the track, and at the times calculated, has now escaped from the penetrating power of the telescope, and is mingling its mysterious cloud-like form with the solar beams.
“The following is a summary of the observations made during its appearance :
"When first observed, its light was considerably inferior to that in the nebula of Andromeda; when again compared with it after an interval of a few days, the inequality had considerably diminished; and as it approached the Sun, before the Moon interrupted the observations on its increasing light, the brilliancy of the nebula (abstracting the central part,) was but very slightly inferior to that of the comet. On a former return of this body, it had been described as appearing like the nebula in the head of Aquarius : on comparing these, the concentration of light was observed to be greater in the nebula than in the comet, but the diffused nebulosity in the former much inferior in brightness to that in the latter ; à condensation of the nebulous matter was constantly obseryed towards the north
of the centre, which might be considered a nucleus or otherwise, according to the various definitions of the term as applied to these bodies. December 9 d. 5 h. 5 m., it was distinctly seen in the twilight notwithstanding the Moon was at that time immediately below the comet. · " Scarcely an evening passed without evidences of its pellucid nature, very small stars being seen through it, conveying the idea of a star-like nucleus. It was remarked, that these stars appeared larger when behind the comet, than when escaped from its nebulosity. Dec. 1 d. 5 h. 15 m. its course was traced by means of a double star, which at this time was enveloped by the southern part of the coma. The comet passed over it obliquely, and at 7 h. 35 m. the star appeared to the east, and quite clear of it.
“ The northern limb was better defined than the southern: in the latter direction the nebulosity seemed more diluted, with occasionally an apparent radiation, but no appearance of a tail : its figure was circular, approaching to an oval. December 11 d. 6h. the diameter a little less than six minutes."
This comet was first observed in 1786; it was seen again in the years 1795 and 1805; no idea, however, had been formed that it was the same body; its identity was not discovered till the year 1819, and its orbit computed by Professor Encke ; he ascertained the largest axis of its orbit to be a little smaller than that of the Asteroid Vesta ; that in its aphelion, it is midway between the orbits of the small planets and Jupiter ; at its perihelion, passes within the orbit of Mercury; that its greatest distance is twelve times its least distance, and its period about 1203 days, completing its revolution in something less time than the Asteroids. · At its return in 1822 it was invisible in this hemisphere, but re-discovered by M. Rumker at Paramatta, New South Wales. In 1825' it was