Part 7

+----------------------------------------------------------------------+ |N.G.C. |[Greek: a]|Precession|[Greek: d]|Precession| Remarks. | | | 1900.0 | | 1900.0 | | | |----------------------------------------------------------------------| | | h m s | s | deg. ' '' | '' | | | 185 | 0 33 27.9| +3.2866 |+47 47 8 | +19.840 | | | 247 | 0 42 11.0| 2.9770 |-21 18 21 | 19.708 | | | 253 | 0 42 38.6| 2.9526 |-25 50 4 | 19.701 | | | 509 | 1 18 9.6| 3.1429 |+ 8 54 40 | 18.894 | | | 516 | 1 18 53.2| 3.1444 |+ 9 1 46 | 18.876 | | | 518 | 1 19 3.0| 3.1428 |+ 8 48 32 | 18.871 | | | 522 | 1 19 30.6| 3.1486 |+ 9 28 19 | 18.857 | | | 524 | 1 19 33.0| 3.1414 |+ 9 1 2 | 18.856 | | | 525 | 1 19 37.9| 3.1464 |+ 9 10 54 | 18.854 | | | 532 | 1 20 2.5| 3.1430 |+ 8 44 35 | 18.841 | | | ... | 1 21 7.3| 3.1493 |+ 9 23 21 | 18.810 |N. G. C. Sup. 114 | | 628 | 1 31 24.8| 3.2141 |+15 16 22 | 18.473 | | | 891 | 2 16 17.7| 3.7447 |+41 53 44 | 16.609 | | | 906 | 2 18 59.5| 3.7502 |+41 38 10 | 16.476 | | |1023 | 2 34 8.1| 3.7387 |+38 37 42 | 15.681 | | |1055 | 2 36 37.5| 3.0739 |+ 0 0 48 | 15.545 | | |1068 | 2 37 33.7| 3.0658 |- 0 26 23 | 15.493 | | |1072 | 2 38 23.7| 3.0715 |- 0 7 8 | 15.447 | | |1084 | 2 41 4.5| 2.9513 |- 7 59 56 | 15.300 | | |1638 | 4 36 33.4| 3.0287 |- 2 0 6 | 7.139 | | |1931 | 5 24 48.7| 3.9695 |+34 10 7 | + 3.067 | | |2366 | 7 18 19.3| 6.4249 |+69 24 51 | - 6.718 | | |2371-2 | 7 19 16.4| 3.7891 |+29 41 13 | 6.797 | | |2403 | 7 27 11.7| 5.8367 |+65 49 13 | 7.445 | | |2624 | 8 32 24.2| 3.4566 |+20 4 24 | 12.370 | | |2683 | 8 46 27.6| 3.7417 |+33 47 51 | 13.317 | | |2841 | 9 15 7.8| 4.1755 |+51 24 3 | 15.080 | | |2903, 5| 9 26 30.4| 3.4065 |+21 56 15 | 15.716 |N. G. C. 2903 and | | | | | | | 2905 | |3003 | 9 42 39.1| 3.5786 |+33 53 9 | 16.553 | | |3021 | 9 45 1.0| 3.5735 |+34 1 14 | 16.670 | | |3031 | 9 47 17.9| 5.0430 |+69 32 14 | 16.785 | | |3079 | 9 55 11.4| 4.1050 |+56 9 34 | 17.147 | | |3115 |10 0 15.1| 2.9877 |- 7 14 6 | 17.372 | | |3156 |10 7 30.5| 3.1107 |+ 3 37 29 | 17.680 | | |3166 |10 8 34.9| 3.1143 |+ 3 55 11 | 17.724 | | |3169 |10 9 4.2| 3.1154 |+ 3 57 41 | 17.744 | | |3184 |10 12 17.4| 3.6158 |+41 55 27 | 17.874 | | |3198 |10 13 47.9| 3.6919 |+46 3 3 | 17.933 | | |3222 |10 17 6.5| 3.2879 |+20 23 30 | 18.062 | | |3227 |10 17 59.1| 3.2864 |+20 24 14 | 18.094 | | |3226 |10 18 2.8| 3.2859 |+20 22 13 | 18.097 | | | ... |10 20 55.2| 4.5248 |+68 55 14 | 18.204 |Coddington's Neb. | | | | | | | in _Ursa Major_.| |3556 |11 5 36.8| 3.5420 |+56 13 0 | 19.485 | | |3587 |11 9 0.1| 3.5029 |+55 33 47 | 19.553 | | |3623 |11 13 42.8| 3.1374 |+13 38 23 | 19.639 | | |3627 |11 15 2.2| 3.1352 |+13 32 18 | 19.662 | | |3726 |11 27 55.4| 3.2764 |+47 34 50 | 19.851 | | |4226 |12 11 28.2| 2.9995 |+47 34 53 | 20.024 | | |4231 |12 11 51.1| 2.9956 |+48 0 46 | 20.022 | | |4232 |12 11 51.2| 2.9957 |+47 59 39 | 20.022 | | |4244 |12 12 29.4| 3.0148 |+38 24 34 | 20.017 | | |4248 |12 12 53.1| 2.9890 |+47 57 52 | 20.016 | | |4254 |12 13 45.0| 3.0509 |+14 58 19 | 20.011 | | |4258 |12 14 0.8| 2.9821 |+47 51 35 | 20.010 | | |4292 |12 16 10.3| 3.0639 |+ 5 9 1 | 19.997 | | |4303 |12 16 48.7| 3.0637 |+ 5 1 42 | 19.993 | | |4321 |12 17 51.0| 3.0418 |+16 22 36 | 19.986 | | |4379 |12 20 11.2| 3.0382 |+16 9 43 | 19.970 | | |4382 |12 20 21.3| 3.0321 |+18 44 45 | 19.968 | | |4394 |12 20 53.0| 3.0310 |+18 46 7 | 19.964 | | |4501 |12 26 56.6| 3.0304 |+14 58 21 | 19.909 | | |4516 |12 28 5.1| 3.0282 |+15 7 38 | 19.898 | | |4527 |12 29 2.2| 3.0629 |+ 3 12 19 | 19.886 | | |4533 |12 29 15.6| 3.0638 |+ 2 52 39 | 19.884 | | |4536 |12 29 20.6| 3.0642 |+ 2 44 22 | 19.883 | | |4565 |12 31 23.3| 2.9812 |+26 32 20 | 19.859 | | |4627 |12 37 7.3| 2.9316 |+33 7 22 | 19.784 | | |4631 |12 37 14.4| +2.9315 |+33 5 19 | -19.783 | | |----------------------------------------------------------------------|

+----------------------------------------------------------------------+ |N.G.C. |[Greek: a]|Precession|[Greek: d]|Precession| Remarks. | | | 1900.0 | | 1900.0 | | | |----------------------------------------------------------------------| | | h m s | s | deg. ' '' | '' | | |4712 |12 44 40.3| +2.9475 |+26 0 55 | -19.667 | | |4725 |12 45 33.0| 2.9434 |+26 2 44 | 19.652 | | |4736 |12 46 10.5| 2.8344 |+41 39 54 | 19.641 | | |4747 |12 46 52.4| 2.9381 |+26 19 8 | 19.629 | | |4826 |12 51 49.1| 2.9499 |+22 13 30 | 19.538 | | |5055 |13 11 20.5| 2.6965 |+42 33 28 | 19.083 | | |5194 |13 25 40.1| 2.5358 |+47 42 43 | 18.663 | | |5247 |13 32 38.6| 3.2368 |-17 22 28 | 18.431 | | |5457 |13 59 40.4| 2.1264 |+54 49 44 | 17.375 | | |5857 |15 2 54.8| 2.7244 |+19 58 56 | 13.993 | | |5859 |15 3 2.2| 2.7245 |+19 58 1 | 13.986 | | |5866 |15 3 45.3| 1.6405 |+56 8 54 | 13.941 | | |5870 |15 3 48.5| 1.6556 |+55 51 50 | -13.938 | | |7315 |22 30 53.4| 2.7270 |+34 17 8 | +18.552 | | |7331 |22 32 24.5| 2.7374 |+33 53 55 | 18.600 | | |7333 |22 32 40.1| 2.7380 |+33 55 44 | 18.609 | | |7336 |22 32 42.6| 2.7377 |+33 57 47 | 18.610 | | |7340 |22 33 4.7| 2.7399 |+33 53 28 | 18.622 | | |7537 |23 9 29.3| 3.0521 |+ 3 57 14 | 19.562 | | |7541 |23 9 38.7| 3.0520 |+ 3 59 21 | 19.565 | | |7778 |23 48 12.9| 3.0635 |+ 7 18 55 | 20.021 | | |7779 |23 48 20.0| 3.0636 |+ 7 19 12 | 20.021 | | |7780 |23 48 25.5| 3.0633 |+ 7 33 44 | 20.021 | | |7781 |23 48 39.2| 3.0638 |+ 7 18 17 | 20.022 | | |7782 |23 48 47.1| 3.0638 |+ 7 24 52 | 20.023 | | |7814 |23 58 7.5| 3.0693 |+15 35 20 | 20.046 | | |7817 |23 58 51.2| 3.0699 |+20 11 46 | 20.047 | | +----------------------------------------------------------------------+

LIST OF ILLUSTRATIONS.

+----------------------------------------------------------------------+ |No. | | +---------------------------------------------------------------| | |N.G.C. No. | | | +-------------------------------------------------------| | | |Date. | | | | +---------------------------------| | | | |Exposure. | | | | | +--------------------------| | | | | |Enlargement. | | | | | | +--------------------| | | | | | |_Orientation_ Top | | | | | | | +----------------| | | | | | | |Remarks. | |----------------------------------------------------------------------| | | | |h m | | | | | 1 | 224 | 1899, September 7 |3 0 | 2.0|W |Great nebula in | | | | | | | | _Andromeda_. | | 2 | 253 | 1902, December 18-20|3 0 | 2.5|S |H V, 1. | | 3 | 598 | 1899, September 12 |3 30 | 2.1|W |M 33. | | 4 | 628 | 1899, October 31 |4 0 | 3.4|S |M 74. | | 5 | 650 | 1899, September 11 |3 0 | 3.4|S |M 76. | | 6 | 891 | 1899, November 6 |4 0 | 3.4|S |H V, 19. | | 7 | 1068 | 1899, December 3 |3 0 | 7.2|S |M 77. | | 8 | .. | 1899, December 28 |4 0 | 2.1|W |_Pleiades_. | | 9 | 1952 | 1899, December 24 |2 0 | 3.4|S |Crab nebula. | |10 | .. | 1898, November 16 |0 40 | 2.2|S |Great nebula in | | | | | | | | _Orion_. | |11 | .. | 1899, February 9 |0 5 | 2.5|S |Great nebula in | | | | | | | | _Orion_. | |12 | 1977 | 1900, January 21 |2 50 | 2.4|S |H V, 30. | |13 | 2024 | 1902, January 28 |3 0 | 2.4|S |H V, 28. | |14 | 2068 | 1902, November 26 |3 0 | 2.4|S |M 78. | |15 | 2264 | 1903, February 23 |3 0 | 2.5|S |Nebula near 15 | | | | | | | | _Monocerotis_.| |16 | .. | 1903, February 26 |4 0 | 2.5|S |New nebula in | | | | | | | | _Monoceros_ | | | | | | | | (Roberts). | |17 | 2403 | 1900, February 27 |4 0 | 3.4|S |H V, 44. | |18 | 2683 | 1900, February 23 |3 20 | 3.3|S |H I, 200. | |19 | 2841 | 1901, April 17 |3 0 | 3.4|S |H I, 205. | |20 |2903-5 | 1900, February 24 |3 30 | 3.4|S |H I, 56, 57. | |21 | 3031 | 1900, March 21 |3 55 | 3.4|S |M 81. | |22 | 3115 | 1901, April 9 |2 30 | 5.0|S |H I, 163. | |23 |3198 | 1900, March 24 |4 0 | 4.3|S |H I, 199. | |24 |3226-7 | 1901, April 10 |3 0 | 3.4|S |H II, 28, 29. | |25_{1}| |{1901, April 9 |0 1 | 20 |S |H IV, 27. | | |3242 |{ | | | | | |25_{2}| |{1901, April 8 |0 10 | 20 |S |H IV, 27. | |26 |3556 | 1902, May 3 |4 0 | 3.3|S |H V, 46. | |27 |3587 | 1900, March 28 |4 0 | 3.3|S |Owl nebula. | |28 |3623 | 1900, April 23 |3 30 | 3.8|S |M 65. | |29 |3627 | 1900, April 23 |3 30 | 4.3|S |M 66. | |30_{A}|3726 | 1900, March 29 |4 0 | 4.9|S |H II, 730. | |30_{B}|3726 | 1900, March 29 |4 0 | 4.9|S |H II, 730. | |31 |4244 | 1900, March 30 |3 0 | 3.7|S |H V, 41. | |32 |4254 | 1902, June 7 |3 19 | 3.7|S |M 99. | |33 |4258 | 1903, May 23 |3 53 | 3.8|S |H V, 43. | |34 |4303 | 1900, April 27 |3 0 | 3.4|S |M 61. | |35 |4321 | 1901, April 19 |3 0 | 4.2|S |M 100. | |36 |4485-90| 1901, April 17 |1 45 | 4.4|S |H I, 197-8. | |37 |4501 | 1902, June 27-28 |3 0 | 3.9|S |M 88. | |38 |4536 | 1903, May 27 |3 30 | 3.3|S |H V, 2. | |39 |4559 | 1901, May 9 |3 0 | 3.4|S |H I, 92. | |40 |4565 | 1901, April 21 |3 0 | 3.3|S |H V, 24. | |41 |4631 | 1902, June 6 |3 0 | 3.3|S |H V, 42. | |42 |4725 | 1902, June 30-July 2|3 32 | 3.4|S |H I, 84. | |43 |4736 | 1902, July 7 |0 30 | 3.3|S |M 94. | |44 |4736 | 1902, July 4 |3 0 | 3.3|S |M 94. | |45 |4826 | 1900, May 27 |2 30 | 3.8|S |M 64. | |46 |5055 | 1902, July 5 |3 30 | 3.3|S |M 63. | |47 |5194-5 | 1899, May 10 |4 0 | 3.3|S |M 51. | |48 |5272 | 1900, May 22 |1 30 | 3.8|S |M 3. | |49 |5457-8 | 1899, June 8 |4 0 | 3.2|S |M 101. | |50 |5857-9 | 1900, May 31 |2 30 | 7.2|S |H II, 751-2. | |51 |5866 | 1902, July 28 |3 0 | 4.9|S |H I, 215. | |52 |5904 | 1900, May 24 |1 30 | 3.7|S |M 5. | |53 |6205 | 1900, June 22 |2 0 | 3.8|S | M 13. | |54 |6218 | 1899, July 11 |2 0 | 3.7|S | M 12. | |55 |6514 | 1899, July 6 |3 0 | 4.1|S | Trifid nebula. | |56 |6523 | 1899, July 7 |4 0 | 2.0|W | M 8. | |57 |6543 | 1899, August 8 |0 5 | 19 |S | H IV, 37. | |58 |6618 | 1899, July 9 |4 0 | 3.1|S | Omega nebula. | |59 |6720 | 1899, July 14 |0 10 | 13 |S | M 57. | |60 |6853 | 1899, July 31 |3 0 | 3.8|S | Dumb-Bell | | | | | | | | nebula. | |61 |6894 | 1899, August 9 |1 0 | 7.2|S | H IV, 13. | |62 |6946 | 1899, August 7 |4 0 | 3.9|S | H IV, 76. | |63 |6995 | 1899, August 29 |4 0 | 2.2|S | Network nebula | | | | | | | | in _Cygnus_. | |64 |7009 |{1899, July 28 |0 10 |}17 |S {| H IV, 1. | | | |{1899, July 30 |0 2 |} | {| H IV, 1. | |65 |7023 | 1903, August 19-20 |3 0 | 3.8|S | H IV, 74. | |66 |7217 | 1899, August 12 |4 0 | 7.1|S | H II, 207. | |67 |7331 | 1899, August 11 |4 0 | 3.8|S | H I, 53. | |68 |7479 | 1899, August 9 |2 0 | 4.8|S | H I, 55. | | | | | {10^s|} | | | | | | | {20^s|} | | | |69 |7662 | 1899, September 5 | {30^s|}17 |S | H, IV, 18. | | | | | { 1^m|} | | | | | | | { 2^m|} | | | |70 |7814 | 1899, September 30 |3 0 | 4.9|S | H II, 240. | +----------------------------------------------------------------------+

FOOTNOTES:

[1] Reprinted from _The Astrophysical Journal_, =11=, 325, 1900.

[2] For a more complete history of this part of the subject, see Dr. Holden's articles in _Pub. Ast. Soc. Pacific_, =7=, 197 _et seq._, 1895.

[3] The difficulties here referred to, about which a good deal has been written, seem to have had their origin in the fact that it was impossible, at the time of the preliminary trials, to provide the observer with an assistant, while the Crossley reflector is practically unmanageable by a single person.

[4] _Mon. Not. R. A. S._, =48=, 386.

[5] Kindly lent by the Astronomical Society of the Pacific.

[6] _Mem. R. A. S._, =46=, 173.

[7] _Mon. Not. R. A. S._, =48=, 280, 1888.

[8] _Mon. Not. R. A. S._, =49=, 297. The construction here described is not followed exactly in the Crossley apparatus. The guiding eyepiece slides freely when not held by a clamp. Pin-holes for preventing fogging are unnecessary when red light is used.

[9] It so happens that the tension of the vertical thread is such that it begins to slacken when the temperature falls to within about 2 deg. of the dew point. The thread thus forms an excellent hygrometer, which is constantly under the eye of the observer. When the thread becomes slack, it is time to cover the mirrors.

[10] _Mon. Not. R. A. S._, =48=, 352.

[11] The following list includes all papers of interest:

"Photographic Observations of Comet I, 1898 (Brooks), made with the Crossley Reflector of the Lick Observatory." A. J. No. 451, =19=, 151; see also _Ap. J._, =8=, 287.

"The Small Bright Nebula near _Merope_," _Pub. A. S. P._, =10=, 245.

"On Some Photographs of the Great Nebula in _Orion_, taken by means of the Less Refrangible Rays in its Spectrum," _Ap. J._, =9=, 133. See also _Pub. A. S. P._, =11=, 70; _Ap. J._, =10=, 167; _A. N._, 3601.

"Small Nebulae discovered with the Crossley Reflector of the Lick Observatory," _Mon. Not. R. A. S._, =59=, 537.

"The Ring Nebula in _Lyra_," _Ap. J._, =10=, 193.

"The Annular Nebula H. IV. 13 in _Cygnus_," _Ap. J._, =10=, 266; see also _Pub. A. S. P._, =11=, 177.

"On the Predominance of Spiral Forms among the Nebulae," _A. N._, 3601.

"The Distribution of Stars in the Cluster _Messier 13_ in _Hercules_" (by H. K. Palmer), _Ap. J._, =10=, 246.

"The Photographic Efficiency of the Crossley Reflector," _Pub. A. S. P._, =11=, 199; _Observatory_, =22=, 437.

"New Nebulae discovered photographically with the Crossley Reflector of the Lick Observatory," _Mon. Not. R. A. S._, =60=, 128.

"The Spiral Nebula, H. I., _55 Pegasi_," _Ap. J._, =11=, 1.

"Photographic Observations of Hind's Variable Nebula in _Taurus_, made with the Crossley Reflector of the Lick Observatory," _Mon. Not. R. A. S._, =60=, 424.

"Use of the Crossley Reflector for Photographic Measurements of Position," _Pub. A. S. P._, =12=, 73.

"Discovery and Photographic Observations of a New Asteroid 1899 FD.," _A. N._, 3635.

"Elements of Asteroid 1899 FD." (by H. K. Palmer), _A. N._ 3635.

[12] Footnote added in 1908: This concluding paragraph, retained in the present publication for completeness, loses point in some particulars, because the photogravure referred to is not reproduced here. The heliogravure reproduction of the Trifid nebula is No. 55.

[13] Since then a photograph by Dr. Roberts has appeared in _Knowledge_, =23=, 35, February, 1900.

Transcriber's Notes:

Passages in italics are indicated by _italics_.

Passages in bold are indicated by =bold=.

Superscripted characters are indicated by ^x.