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Summer
Signs.

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Autumn
Signs.

Sun enters.

Continues. (4. c. (Cancer.) June 21, 6h. 42m. A.

31 10 48 5. 2 (Leo.) July 23, 5h. 30m. M.

31 6 29 6. m (Virgo.) August 23, 11h. 59m. M.

30 20 44 Sun in the Summer Signs

93 14 1 Sup north of the Equator, for interval between the beginning of Spring and of Autumn

186 11 19 7. ^ (Libra.) Sept. 23, 8h. 43m. M.

30 9 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. Ve (Capricornus.) Dec. 1829, 21, 8h. 11m. A. 29 10 22 11. (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 Length of the tropical year, commencing at the winter sol

stice, 1829, and ending at the winter solstice, 1830 365 5 49

Winter
Signs.

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ECLIPSES OF THE SUN AND MOON IN 1830; Those of the Moon happen on the 9th of March and 2d of Sept., and will be visible in part; those of the sun will be altogether invisible, in the United States. 1. February 22 and 23, the Sun eclipsed.

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. 42in. A.

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 north west 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. 1m. 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. Beginuing of the general eclipse 6h. 28m. M. app. time at Washington. Beginning of total darkness

7 31 Middle of the eclipse

8 24 End of total darkness

9 18 End of the general eclipsc

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.

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III. March 24, the Sun eclipsed. Beginning of the general eclipse, in Lat. 73° 41' S., Long. 258° 59' E.,

7h. 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

12 Digits eclipsed, 1° 121.

5

IV. August 18, the Sun eclipsed. Beginning of the general eclipse, in Lat. 56° 21' S., Long. 58° 43' W.,

6h. 10m. M., apparent 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. 54 m. M.

Visible in the South Frozen Ocean.

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V. September 2, the Moon totally eclipsed.

Boston. IN. York. Wash'n. Charles'n. N. Orleans. h. m. h. m. h. m. h. m.

h. m. Beginning of the general eclipse 4 5a. 3 54 a. 3 424a. 3 30 a. 2 494 a. Beginning of total darkness 5 33 4 51 4 40 4 281 3 471 Middle of the eclipse

5 538 5 42 5 301 5 188 4 373 Moon rises eclipsed .

6 30 16 28 6 26 6 23 6 22 End of total darkness

6 44 16 324 6 203 16 9 5 278 End of the general eclipse 7 414 17 30 17 184 17 68 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.
8 4

32 30
7 50

20 21 ng 36

8 12 7 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.

41m. A.

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.

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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.

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.

8 16 South 1869 Aug. 7.

10 11 1975 Sept. 29.

11 25 Annular. 1878 July 29.

7 21 on the South Limb. 1885 March 16.

6 28

North 1892 Oct. 20.

8 12

South 1900 May 28.

1) 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. S 11' 19" South of the centre Emersion 11 12 0,4

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Jan. 16. Occultation of 9 m.
Star rises eclipsed Jan. 15, 11h. 38m. Os. A. S
Emersion
Jan. 16, 0 28

.centre. February 10. Occultation of T 82. Immersion

2h. 36m. 10s. M. S 3' 51" North of the Emersion

3 56 33 { 5 40 ) centre. March 6. Occultation of 2. Immersion

10h. 4m. 36s. A. S 3' 6" South of the Emersion

11 30 27

1 393 centre, March 12th and 13th. Occultation of x M. Immersion

March 12, 11h. 33m. 32s. A. S 9' 51" South of the Emersion

13,0 35 59 M. 8 0 S centre. March 28. Occultation of Aldebaran. Immersion

5h. 6m. 12s. A. S 41 5911 North of the Emersion

6 19 32

23S centre. April 7. Occultation of 9 m. Immersion

8h. 39m. 47s. A. S 7' 51" South of the Emersion

9 48 10 6 34 3 centre. May 2. Occultation of T 22. Immersion

9h. 46m. 59s. A. S 1' 48" South of the Emersion

11 10

0 13 centre. May 22. Occultation of Aldebaran. Immersion

1h. 19m. 49s. A. S 5'43" South of the Emersion

2 30 53

5 51 S centre. June 2. Occultation of 2 m. Immersion

6h. 46m. 21s. A. S 11' 54" 5 South of the Emersion

: 7 41 10 { 9 58 centre. July 6. Occultation of d 4. Immersion

3h. 8m. 22s. M. 5 12 181 South of the Emersion

3 48 27

13 20 centre. July 10. Occultation of a mano Immersion

Oh. 15m. 285. M. S 15' 15" North of the Emersion

0 34 20 ( 15 403 centre, July 16. Occultation of Aldebaran. Immersion

5h. 34m. Os. M. S 13' 91' | North of the Emersion

6 21 18 { 10 33 centre. August 12. Occultation of y 8. Immersion

4h. 37m. 10s. M. S 0' 21" South of the Emersion

5 53 6 { 3 51 ) centre. August 29. Occultation of d f. Immersion Emersion

8 53 35 10 50 centre.

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September 3. Occultation of g h. Immersion

2h. 38m. 59s. M.S 41 911 South of the Enersion

3 43 55

? 4 59

centre. October 4. Occultation of f 8. Immersion

9h. 44m. 588. A. S 15' 0" South of the Emersion

10 6 40

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October 27 and 28. Occultation of

ф Immersion

Oct. 27, 11h. 58m. 46. A. S O 4311 South of the Emersion

2 39 M. { 1 2 3 centre. November 2. Occultation of y 8. Immersion

5h. 36m. 50s. M. 15! 531 , South of the Emersion

5 59 27 {15 10 S centre. November 19. Occultation of d 4. Immersion

7h. 36m. 25. A. S 21 431 North of the Star sets eclipsed

8 1

centre. November 29. Occultation of Aldebaran. Immersion

9h. 6m. 59s. A. S 5/ 33" North of the Emersion

10 15

? 1 34 ) centre. December 27. Occultation of y 8. Immersion

3h. 24m. 453. M. 5 11' 31" South of the Emersion

6 39 { 923 centre. The importance of occultations of stars by the moon, in the determination of terrestrial longitude (the latitude being always very easily ascertained), has long been known. The longitude deduced from the observed immersion or emersion of a star will be as near the truth, as the result of hundreds of lunar distances, or of a large number of transits of the moon and a star; but when the lunar tables are relied on, the longitude, even thus obtained, is liable to some uncertainty, on account of the small error which is sometimes found in them.

For the determination of the longitude, those occultations are most suitable, in which the stars disappear or reappear near the centre of the moon, as the time of either of their phenomena taking place is then less affected by an error (should there be any) in her tabular longitude or latitude; particularly in the latter; the longitude, however, deduced from a corresponding observation of the same occultation, made in one of the observatories of Europe, or in any other place, whose geographical position is well determined, will be free not only from error on this account, but from every other but that of observation.

Of the seven occultations of Aldebaran which will be visible this year in some parts of the United States, four (those of Jan. 5, May 22, July 16, and Nov. 29,) will likewise be visible in Europe. An opportunity is thus presented, of ascertaining with very great precision the longitude of many of our cities and points on our coast, at present inaccurately known, which may not again occur for several years.

On another account, the subject of occultations has at all times been an interesting and important one, both to the practical and theoretical astronomer; viz. that they frequently present some remarkable phenomena with respect to light, when the edge of the moon comes in contact with the star about to be occulted, the star sometimes appearing to be projected on the disc of the moon. This circumstance has lately been very particularly attended to, and numerous instances given by the Astronomical Society of London, who suppose that this appearance is more frequent (or at least more frequently recorded), as to Aldebaran, than in the case of any other star, accompanied, however, with anomalies for which it is difficult to account."

It is therefore hoped that our astronomers will be induced to look out for the occultations of this star, not only with a view to ascertain the longitude of the place of observation, but to determine whether it does not appear projected on the face of the inoon; in doing this, particular attention should be paid to the following circumstances.

* See a paper read before the Astronomical Society of London, by Mr. South, the Vice President, Jan. 1829.

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