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tion of half her motion between the first and second, + 8”.6; hence her longitude at that time is 9° 46' 7"'.6.
The Occultations (pages 4, 5, 6,) were computed with the greatest strictness, and so very nearly accurate are the Lunar Tables, that these interesting phenomena can be predicted with the certainty that they will take place almost at the precise moment. Indeed, that of Aldebaran, on the 18th of September last, actually happened at Boston, at the very second; that of the 21st of August within three seconds, and that of the 12th of November within ten, although the last took place near the edge of the moon, and in a position to be most affected by an error in her tabular longitude.
We cannot refrain from expressing to M. Encke, our great obligą. tion for the assistance we have received from his Astronomical Year-Book for 1830. “ This work” (says Mr. Baily, \first Vice-President of the London Astronomical Society.) “ should be hailed as the harbinger of a general improvement in the mode of arranging and forming the ephemerides of different nations. M. Encke, disdaining the trammels of former and less enlightened times, and relying on his own excellent judgment and abilities, has nobly and boldly struck out a new path for himself, which, there can be no doubt, will soon be followed by every nation pretending to encourage the science of Astronomy.'
Although it is mortifying to reflect that this country cannot, or will not, attempt to attain eminence in this and other scientific pursuits, yet we should be grateful for information, wherever it can be found, and hope we may be able, eventually, to emulate the splendid example that has thus been set us.
To the English Nautical Almanac we are indebted for some of the elements here published. This work, though not to be compared with that of which we have just spoken, is, we apprehend, harshly mentioned by Ms. Baily, when he calls it “an unnecessary expense” and “ a disgrace to the nation;" although it must be confessed to be singular, that, for a period of nearly thirty years after the discovery of four new planets, not the least notice should be taken of any one of them, and that the longitude of the Sun and his distance from the Moon (so important in the determination of terrestrial longitude) should still be computed from Delambre's tables, even after their errors had been pointed out, and the amount of them in 1829 actually calculated, in the Supplement to the Almanac for that year. Perhaps, however, it may be thought, that Americans have not the least right to complain of the defective state of the English Nautical Almanac, when they, so far from having ever attempted to produce a better, have done little to advance the noble science of Astronomy.
Although great care has been taken to avoid errors, a few escaped notice until the opportunity for correcting them had passed; perfect accuracy, it would seem, cannot be attained, since even in the Berlin Year-Book, computed and edited, as it was, by the greatest astronomers, a considerable num. ber of typographical errors is to be met with. Moreover, the time of the passage over the meridian of all the planets, as therein given, is for the most part incorrect; that of Mercury and Venus being one day too late, when they south before noon, and that of all the others being correct, only, when they south about midnight.
The year 1831 will be distinguished for astronomical phenomena worthy of the attention of our astronomers. Besides the eclipse of the Sun on the 12th of February, which will be very large throughout the United States, and annular in some part of Louisiana, Mississippi, Alabama, Georgia, North Carolina, Virginia, and Massachusetts, there will be eight visible occultations of Aldebaran, three of Jupiter, three of Saturn, two of Regulus, one of Venus, and one of Uranus, as well as of a great number of the smaller
CALENDAR, AND NATURAL PHENOMENA FOR THE YEAR.
THE PLANETS, &c. O The Sun.
h Saturn. Ô The Earth.
H Herschel or Uranus. OI The Moon.
ŏ Conjunction. ♡ Mercury
19 Lunar Cycle, or Golden Number 7 Roman Indiction Epact 6 | Julian Period
March 3d, 5th, and 6th.
September 15th, 17th, and 18th.
MOVEABLE FEASTS IN 1830.
Trinity Sunday, June 6.
Advent Sunday, Nov. 28.
SIGNS OF THE ZODIAC, With the time of the Sun's entrance into, and continuance in, each of
1, op (Aries.)
3. Ő (Gemini.)
March 20, 9h. 24m. A.
Continues. 4. O (Cancer.) June 21, 6h. 42m. A.
31 10 48 5. 2 (Leo.)
July 23, 5h. 30m. M. 31 6 29 6. (Virgo.)
August 23, 11h. 59m. M. 30 20 44 Sun in the Summer Signs,
93 14 1 Sun north of the Equator, or interval between the beginning of Spring and of Autumn,
186 11 19 7. ~ (Libra.) Sept. 23, 8h. 43m. M. 30 8 16 8. m (Scorpio.) October 23, 4h. 59m. A. 29 20 30
9. Sagittarius.) November 22, lh. 29m. A. 29 12 31 Sun in the Autumnal Signs,
89 17 17 10. Vo (Capricornus.) Dec. 1829, 21, 8h. 11m. A. 29 10 22 11. Se (Aquarius.) Jan. 1830, 20, 6h. 33m. M. 29 14 40
12. H (Pisces.) Feb. 18, 9h. 13m. A. 30 0 11 Sun in the Winter Signs,
89 1 13 Sun south of the Equator,
178 18 30 Sun north of the Equator,
186 11 19
ECLIPSES OF THE SUN AND MOON IN 1830 ;
be visible in part; those of the Sun will be altogether invisible, in the
Beginning of the general eclipse (or the penumbra of the moon first touches the earth), in Lat. 46° 9' North, and Long. 46° 24' East from Greenwich, Feb. 22, at 10h. 29m, A., apparent time at Washington.
Greatest obscuration (3° 42') in Lat. 71° 19' N., Long. 48° 58' E., at 11h. 42m. 1.
End of the general eclipse, (or the penumbra leaves the earth), in Lat. 75° 2' N., Long. 137° 57' E., Feb. 23, at Oh. 56m. M.
Visible to a great part of the northwest of Asia, and to the eastern portion of European Russia. The western line of contact passes through the circle of Long. of about 32 E. ; so that at St. Petersburg there will be no eclipse. At Kasan the eclipse will begin at sunrise, Feb. 23, at 7h. Im. M. apparent time at Kasan, and will end at Sh. 23m. M.
Digits eclipsed, 2° 54'.
At Moscow the Sun will rise eclipsed. The end will take place Feb. 23, 7h. 29m. M. apparent time at Moscow. Digits eclipsed, 2° 18'.
II. March 9, the Moon eclipsed.
8 24 End of total darkness
9 18 End of the general eclipse 10 19
At New Orleans. Beginning of the eclipse
5h. 35m. M. app. time at New Orleans. Moon sets eclipsed
6 9 The geographical positions of the places to which the Moon will be vertical at the time of the above phases, will be found in the following table; by means of which it will be very easy to determine where the eclipse will be visible.
III. March 24, the Sun eclipsed. Beginning of the general eclipse, in Lat. 73° 41' S., Long. 258° 59' E.,
Th. 55m. M., apparent time at Washington. Greatest obscuration (6° 12' digits) in Lat. 72° 0' S., Long. 47° 45' E.,
9h. 24m. M. End of the general eclipse, in Lat. 37° 24' S., Long. 28° 40' E., 10h.
54m. M. This eclipse will be visible in the South, Atlantic and Frozen Oceans.
At the Cape of Good Hope. Beginning of the eclipse at
4h. 20m. A. app. time at the Cape. End
5 12 Digits eclipsed, i° 12;.
IV. August 18, the Sun eclipsed. Beginning of the general eclipse, in Lat. 56° 21' S., Long. 58° 43' W.,
6h. 10m. M. app. time at Washington. Greatest obscuration (1° 30') in Lat. 70° 48' S., Long. 81° 5' W., 7h.
2m. M. End of the general eclipse, in Lat. 76° 24' S., Long. 2° 6' W., 7h. 54m. M.
Visible in the South Frozen Ocean.
Boston. N. York. Wash'n. Charles'n. N. Orleans
h. m. Beginning of the general eclipse 4 5&a. 3 54 a. 3 424a. 3 303 a. 2 49} a. Beginning of total darkness 15 31 4 518 4 40 4 28.1 3 474 Middle of the eclipse 15 535 42 5 304 15 18%
4 375 Moon rises eclipsed
6 30 6 28 6 26 6 23 6 22 End of total darkness
6 44 6 324 6 203 16 9 5 274 End of the general eclipse 17 418 7 30 17 184 17 69 6 251
At Boston and New York the Moon will rise totally eclipsed. At the above times the Moon will be in the zenith of the following places.
Lat. 8° 20' South. Long. 46° 28' East.
20 21 7 36
8 12 ng 20
5 26 West.
VI. September 16, the Sun eclipsed. Beginning of the general eclipse, in Lat. 75° 59' N., Long. 70° 28' E.,
7h. 30m. A., app. time at Washington. Greatest obscuration (4° 42') in Lat. 72° 4' N., Long. 116° 27' W., at 9h.
6m. A. End of the general eclipse, in Lat. 40° 39' N., Long. 144° 58' W., 10h.
This eclipse will be visible in the northwest part of North America, and in the northeast part of Asia.
The solar eclipses this year happen at such a distance from the moon's node, that not one of them will be total in any part of the earth.
Solar eclipses have been, of late years, very rare in the United States ; only two having taken place since 1823; but in the next eight years no less than five will be visible; all of which will be very large, and three central.
During the remainder of the present century, twenty-eight will be visible at Boston, of which the following are those whose magnitude will exceed 6 digits.
1831 Feb. 12. digits eclipsed 11° 26' on the South Limb. 1834 Nov. 30.
10 28 1836 May 15.
8. 6 1838 Sept. 18.
10 51 1846 April 25.
6 41 1854 May 26.
11 21 Annular. 1860 July 18.
6 13 on the North Limb. 1865 Oct. 19.
South 1869 Aug. 7.
10 11 1875 Sept. 29.
11 25 Annular. 1878 July 29.
7 21 on the South Limb. 1885 March 16.
6 28 6 North 1892 Oct. 20.
South 1900 May 28.
11 1 The eclipse of Feb. 1831 will be annular in the northern part of Virginia, in the island of Nantucket, and in Halifax, Nova Scotia.
The eclipse of Nov. 30, 1834, will be total in Charleston and Beaufort, S. C. and vicinity.
The eclipse of May 15, 1836, will be annular in the West Indies, and in the city of Edinburgh, G. B.
The eclipse of Sept. 18, 1838, will be annular in the western part of Connecticut, New York, New Jersey, Pennsylvania, Maryland, Delaware, Virginia, and part of North Carolina, and central at Washington.
The eclipse of May 26, 1854, will be annular in Boston, and part of New Hampshire and Maine.
The eclipse of Oct. 19, 1865, will be annular at Wilmington, N. C. and in Charleston, S. C. and their vicinity.
The eclipse of August 7, 1869, will be total at Wilmington, N. C. and in part of Virginia.
The eclipse of Sept. 29, 1875, will be annular at Boston, part of New Hampshire, and part of Maine.
The eclipse of May 28, 1900, will be total in Virginia, a little south of Norfolk.
The last total eclipse of the Sun at Boston happened on the 16th of June, 1806.
The last total eclipse in any part of the United States (at Cape Roman, Florida), on the 9th of December, 1825.
OCCULTATION OF STARS BY THE MOON IN 1830, Visible at Boston, and other parts of the United States; the Phases of
which are expressed in mean solar time for the meridian for Boston. January 5. Occultation of Aldebaran. Immersion
10h. 14m. 51s. .0 A. Sil' 19" South of the centre Emersion
11 12 0.4 11 13 ) of the Moon.