None
Groombr. 3519.. — O'22 — C}'9 I 2356.. +0-32 3301.. + O'12 3660.. — O'12 7 Groombr. 2329.. + o'o6 Sept. i + 0-09 16 Groombr. 4086.. — o'o6 ^— cvo7 2356.. +0-26 + 0-25 4089.. — O-09 ^^ \J / 2405.. +0-42 6 Groombr. 2821.. + 0'13 + 0-13 23 — 0-07 8 Groombr. 2329.. + O'13 7 + 0-05 26 Groombr. 3486.. — O'O 2356. 4-0-08 + OM6 4086.. — O'O 2405.. 4-0-29 8 Groombr. 3301.. — O'O 4089.. — O'O2 3667.. -0-03 — O'O1 ii Groombr. 233 7.. +0'16 3711.. O'OO 29 Pol. S.P. & Pol. — 0-03 — 0 "O ^ 2410.. -4-0-18 4-0-16 2413. + 0'12 1 1 Groombr. 2821. — 0-06 3' Groombr. 3735.. — O'lO — o-io Z4'9" +0-19 3301.. 4-0-21 3667.. 4-0-1 1 +0-04 Nov. 7 Groombr. 3377.. -0-17 '5 Groombr. 2337.. -0-15 3711.. — 0-08 3756.. -0-23 — 0-19 2372.. + 007 36.. — 0-16 2391.. + O-O2 + 0'12 12 Groombr. 3301.. — 0-02 "9 2372.. + 0-15 3648.. — 0-01 10 Groombr. 3377.. — O'lO 2391.. + 0-22 3667.. +0-07 + o'oi 13.4- — 0-07 371 1.. — OM2 Dec. 6 Groombr. 3478.. — O'OI 404.. + 0-09 3479- + 0-06 569.. — O'O 22 Groombr. 3735 •• -0-15 404.. — O'O5 7 Groombr. 404.. — O'OI — O'OI '9 Groombr. 547.. — O'OI 547- + 0-03 — O'I I 562.. 569.. — O-19 -0-25 — 0-16 562.. — O-27 8 Groombr. 758.. — O-06 — O-06 24 Groombr. 3377.. 3384- — O-16 + O-QI — O-08 28 Groombr. 3478.. — O-06 — O-06 -0-03 -0-13 Adopted Right Ascensions of Stars used for the Determination of "n" in 1813. Star's Name. R.A. 1813. Approx. S. Tan 8. Authority. Star's Name. R.A. 1813. Approx. S. Tan S. Authority. C. Polaris (235) O. 5 5. 2 1/29 88. 19 Groombridge 2193 C. 4 1/29 7C. 4.5 7-Q7 I 3 T J 240 1... 16. CC. 55'sO 67. 46 2'45 2 Groombridge 126 O. 72. 28*94 He c 3-7 1 24 1 2 J J 17 0 7 7-38 6q. 28 T J 2-67 2  108 2 1228 6 4O 1*24 71 2 2 3182  76. 18 A* \ 3233 20. 2§. 14-47 cq. 47 72 2 lioq... / 3 3 T3 * / 7 ? C 4.4."78 76. 28 T- * * 4." I 6 I ^247 2O. j2. 31*69 ^7 T ' 69. 2 •6 1 2 T 7 -• 1412 / ' 33- TT / 7-57- 10-32 76.27 4-15 I 3250 20.33- 55'36 60. 6 3 H'7 7- 59- "-32 75-23 3-84 3 3254 20. 34. 30-58 69. 2 •6 1 2 '522 9. o. 18-44 74-47 3-68 4 3263 20. 36. 18-90 59-50 72 2 1561 9.23.44-86 78.58 5''3 3 3274 20. 38. 39-49 59- 55 73 2 1687 10. 36. 12-90 76. 59 4'33 3 3298 2O. 42" 28-66 57-44 •58 2 1704 10.43.45-63 71. o 2-91 i 33°9 20.44.47-57 58. 3 •60 3 1728 TO. 50. 5077 77-27 4-50 i 3328 20.47. 53'43 57-57 •60 2 "735 10. 55. 27-10 78.48 5-06 2 3536 21.33. 9'98 56.39 •52 N 1747 ii. 2. 0-55 79-20 5-32 2 3587 21.43.31-48 53.22 '35 3 1803 11.25.41-31 78 38 4-98 3 3605 21. 46.47-32 53- 7 '33 3 1852 'MS- 34-34 77- 57 4-69 N 3611 21. 48. 21-50 53- 3 '33 3 1868 12. 10. 18 93 76. 12 4-08 6 3671 21. 57.49H9 65. 10 2-16 4 1987 13. 16. 22-43 55- 54 1-48 N 3778 22. ig. 30-23 74- 3 3-50 2 200 1 13. 21.22-79 73.22 3'35 N 3834 22.28. 56-73 75- "5 3-80 N 2029 13.32.42-57 72. 12 N 4O02 23. I.58-95 74-23 3'57 N 2125.... 14. 26. 38-74 61. 3 1-81 N 4"9 23. 31. 14-00 74- '5 3-55 2 2147 '4- 37- 54-45 73- 6 3-29 3 4120 23- 3'- '7'28 72.58 3-26 3 2180 14. 56. 2C-2g 75.38 3-91 i 4I24 23- 3-- 54-79 74-43 3-66 2 2185 14. 58. 1878 75- 39 3-91 i 23- 33- iz'93 74-33 3-61 2 2186 14. :8. 48-01 75- 4' 3-92 I 4'54 23- 43.24-26 74- 3° 3-60 4 RIGHT ASCENSIONS. Determinations of"n" in 1813. xxix Date 1813. Polar Star. Observed Values of n. Adopted Values of Date .8,3. Polar Star. Observed Values of n. Adopted Values o n. Date 1813. Polar Star. Olwerved V:, lll.v. Of n. Ailoptei Values o M. West. West — continued. East — continued. Jan. 2 8 Groombr. 908.. Groombr. 4120.. s — 0'12 + 0'O2 s — O'l 2 Mar. 1 7 Groombr. 1228.. 1239.. s + 0-09 — 0-09 s O'OO May 13 Groombr. 2125.. 2147.. s ~4~ o* 2c -|— Q" | ] 8 + 0'23 126.. 762.. + O'2O + 0-16 + O'I3 26 Groombr. 1228.. 1561.. + 0'OI +o'o6 1 A* • fj 16 Groombr. 1868.. +0-01 + 0-01 10 Groombr. 4120.. 4154.. -f-O'OI — O'lO 1687.. •735- + 0'2I + O'4O \ V I y '9 Groombr. 1868.. — o-o6 — O'OC 126.. + 0-04 O'OO 2125.. — 0-03 J 436, — o 06 3' Groombr. 1228.. + O'I4 758.. + 0'IO 1561.. + 0'25 + *%• A f* o 20 22 Groombr. 1868.. -0-14 -0-14 16 Groombr. 436.. 908.. + 0'OI — O'02 April i Groombr. 1687.. + O'I7 24 O'OO >735- + O'12 + O'2O 24 Groombr. 762.. — 0-05 — 0-05 I747-. -j-0'20 26 Groombr. 2001.. 2029.. + O'22 + 0-3I + 0-16 10 Groombr. 1852.. O'27 27 Polaris — O'OC 28 + 0'05 / J Feb. 7 Groombr. 1408.. + 0-14 + 0-14 1 1 Groombr. 1852.. + 0-18 + 0-18 29 Polaris S P — 0-07 — 0-07 9 + 0-M 12 + O'2I 3' Groombr. 2001.. 2029.. + 0-13 + 0-06 + 0-10 13 Grpombr. 1852.. + 0-25 + 0-25 10 Groombr. 1408.. + 0-09 + 0-09 June 2 Groombr. 2001.. + 0-13 16 Groombr. 1704.. + 0-10 + 0-09 2029.. + 0-18 + 0-15 '3 + 0-10 1735- + 0-02 7 Groombr. 1987.. -0-27 16 Groombr. 1408.. + 0-12 + 0-01 26 Groombr. 1728.. — 0-03 2125.. + 0-05 — O'l 1803.. — O'OI 24 Groombr. 1408.. + O'2I + O'2I 8 Groombr. 1987.. — 0-26 May z Groombr. 1852.. + O'IO + O'IO 212;.. — 0-06 ~~ O'I O 27 (iroombr. 1408.. + 0-21 -f-O'2I East. I 2 Groombr. 1987.. + 0-17 + 0-17 28 Groombr. 1408.. + 0-15 + 0-15 May 8 Groombr. 1852.. + 0-16 16 Groombr. 2180.. + 0-04 Mar. 1 4-0-15 2001.. 2029. + 0-14 + 0-07 f O'l I 2185.. 2186.. + 0-18 + 0-28 + 0-25 2'93- + 0-49 3 Groombr. 1398.. + 0'14 9 Groombr. 1852.. + 0-08 1408.. 1412.. Jo'lo" + 0-16 ZOOI.. 2029.. + 0-07 -fo- O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O'O' East — count imii'il. 8 s a s n July 1 1 Groombr. 2401.. + 0-05 | Q 'QQ Aug. 1 6 Groombr. 2980.. + 0-17 Oct. 29 Groombr. 3834.. — 0-02 2412.. + 0-12 3007.. + 0-28 -0-15 '7 2980.. + 0-24 -j- w ~if 3007.. + 0-24 3' Pol. & Pol. S.P.. -0-13 -0-13 12 Groombr. 2401.. + 0-02 O 'OO 2412.. — 0-02 20 Groombr. 3060.. + 0-24 Nov. 1 1 Groombr. 4002.. + 0-06 + 0-06 3103.. + 0-35 -4- 0-2 1 17 18 Groombr. 2401.. + 0-05 + 0-04 3247- 3254- + 0-16 + 0 Pol. S.P. & Pol.. — 0'12 — 0-12 — 0-03 31 Groombr. 3605.. + 0-09 9 — 0'06 361 1.. + 0-08 25 Groombr. 3263.. 3274- — 0'12 — 0-07 _L o' 10 Sept. 2 3587- 3605.. + 0-06 — 0-16 + 0'01 H Groombr. 3536.. + 0-00 O'OO 33°9- + 0-23 3611.. — 0-17 3328.. + 0'35 5 3071.. + 0-16 '5 Groombr. 3536.. + 0-18 4-0'07 4002.. — 0-03 i ** v / 26 Groombr. 3263.. 3274- + 0-07 + 0-04 6 Groombr. 3671.. O'OO O'OO 20 Polaris — 0'12 — 0-12 3309.. +0-10 9 Groombr. 3671.. — 0-17 3328.. -fo'i6 22 Groombr. 516.. + 0-19 28 3263.. -0-03 3274.. +0-18 + 0-08 H Groombr. 2640.. + 0'12 + 0-12 27 | Groombr. 4119.. — 0-05 3*74- + 0-21 573- + 0-08 -f~ O'OI "7 Groombr. 2640.. + 0-10 + 0-10 Aug. 2 Groombr. 3051.. + 0-06 29 Groombr. 3778.. + 0-13 3 4 3°5>- 3051.. + O-21 + 0-06 + 0-04 "9 Groombr. 2640.. 3834- +0-15 — 0-08 + 0-03 573 — 0-08 -j- O'O2 3211.. — 0-06 3233- 3250.. O'OO Dec. 12 Groombr. 41 19.. — 0-10 — 0-10 3834- + 0-12 15 Groombr. 3778.. — 0'02 7 Groombr. 3182.. + 0-03 Oct. 9 + 0'02 4119.. -0-03 — 0'02 3183.. + 0'11 + 0-03 215.. — 0'02 3298.. -0-25 10 + O'O2 9 -fO'IO + O4IO 1 1 Groombr. 3834.. + 0'02 + 0'02 26 Groombr. 4124.. 4129-. 215.. — 0-05 + 0-32 + O'O3 + 0-08 13 Groombr. 3834.. — 0-1 I — 0'16 573- + 0'04 Groombr. 3182.. + 0-16 4002.. — O'22 3183.. + 0-36 + 0-18 3' Groombr. 215.. — O'12 3298, + 0-03 25 Groombr. 3834.. + 0-03 + 0-03 573- -0-14 — 0'13 RIGHT ASCENSIONS. XXXI Adopted Right Ascensions of Stars used for the Determination of "n" in 1814. Star's Name. E.A..814. Approx. O. Tan 8. Authority Star's Name. K. A. 1814. Approx. Tan J. Authority. Polaris (2 3 5) h in in s o. ec. 35-3;? o / 88. iq 34/03 N Groombridge 1706 h in in a 10. 44. 41-61 78.46 5-04 N 1720 10. iq. 26-36 ~~ 2V4C 71. 27 3-36 1728... 10. 50. 50. 50 77- *7 4-50 2 2Q O. C. C2'23 7C. CC VQQ N IQ4-3--- 12. 40. 38-62 69. 38 270 3 1 A 9 o t7 x\o; 76. c6 4" <O IQ4.6 12 (I. i 3-qq 6q. 43 2-71 3 2 i ; o. ci. 41-00 73. 22 7*14 6 1047 12. 52. 5-49 69. 47 2-72 3 2 1O O. C1 J.7'O1 7Q I C'l C »»*/ 216;. 14.47. 6'io 66.25 2-29 2.12 0 c6 18-82 78 41 C'OO N 2180 14. c6. 24'QC 75- 38 3-91 3 too I 41 Q'o6 72. 11 1' I 2 2181... 14. C 7. 0-78 66. 13 2-27 i CIO 2. 1 8. 38-96 60 J.Q 2*72 2 2184.. H. ^7- 4-V4-6 78. 56 5-1 1 2 s22 2. IQ 8'Q7 70 c 2-76 2 2i8c 14. c8. 18-26 75- 38 3-91 3 C82 2.4.4. IO-27 70 2 C C'lC 2 22 I. C. IQ. IO'6l 62.43 1-94 2 >7* 603 2 C2 C2'68 70- 17 C'J-S 2 226l .. It. 55. 21'CO 68.26 2-53 2 614.... 2. -;6. 7'Cq 70. 4-4. ?"s I I 26l7... 18. 30. 4Q-qi 65. 18 2-17 2 -63 3. 4.4. iq'I7 78. 10 4-*Q2 4 264.0 18 3C- 37'Q3 6s. iq 2-18 N 827 A l CQ-4C 70. Q 2-77 3082 20 6 14*14 72. 14 3-12 6 q+8... C. 3. 10-83 74- 21 VC7 1 1 IO7... 20. q. 22'CO 67. 44 2 '44 3 OC2. C 4 ll'S Q H7 7'C I ] 71 I 2 20 10 4'oq 67. 43 2"44 3 062.. C. 12 CI '17 74. 10 3* C 3 2 I 4.7 20 14 J2'18 72. 1q 1*14 3 07O. C. 16. 7'C4. 74. 7 VC I 2 1 I c6 20 16. I i'6z 72. 2 i'o8 3 081 C IQ. 1 1"1O 71 N I ?'4.C 2 1122 2O 47. 7*1 I 68. 58 2 "60 4 086. C 21. CC'74 74. 10 v6i 2 HCQ 2O. C2 c6'47 6q. 14 2*64 2 QQ1 c 24. 4&'8c 7C 17 2*QO I 1778 22 iq 1 I'2C 74. 4 3'sO 4 I H7 7 24. 4.C-I; 74. 2s J Vv 1'CQ 2 J.OQ1 21 2C 46'8l 71. 12 3-31 3 I 14.2 .. 7 2C lq'2I 74 28 i'6o 41 7O 21 47 l8'6q 73. 6 3-20 4 i 161 .., 7. 1O. C4'21 78 2 J.'72 t 4.2 IQ 21 -;8 c6'ci 71. 1 1 3-30 4 i i6c... 7. 11. I7'8l 78 7 X'7C T* J7 Determinations of" n " in 1814. 1814. Polar Star. Observed Values of n. Adopted Values of n. Date 1814. Polar Star. Observed Values of n. Adopted Values of n. Date 1814. Observed Polar Star. Values of n. Adopted Values of n. East. East — continued. East — continued. s • 8 a 8 s Jan. i Groombr. 399.. — 0-18 — O' 1 I Feb. 4 Groombr. 962.. + 0'I2 Feb. ii + 0-01 215.. 7 Grojiubr. 519.. — 0-04 — 0-22 — O'I7 97°-. 98... 986.. + 0-03 + 0-03 + 0'08 + 0-06 20 Groombr. 827.. 986.. — 0-03 -0-13 —0-08 9 522.. — 0'12 / -0-17 6 Groombr. 962.. 981.. 986.. + 0-09 + O-O6 — O'03 + 0-04 21 Groombr. 1337- 1361.. 1365.. -0-18 — 0-12 — O-O7 — O'lZ Feb. i Groombr. 763.. + 0-01 23 Ciroombr. 1342.. + 0-06 cvn-» 948.. — 0-05 — 0-08 7 Groombr. 948.. +0-16 1361.. — O'lO "~~ U UZ 952.. — 0'02 952.. + O-02 + 0'IO 993- -0-2J 962.. + 0-1 I H — O'O2 xxxn INTRODUCTION TO GEOOMBRIDGE CATALOGUE. Determinations of'n" in 1814 — continued. Date 1814. Polar Star. Observed Values of 71. Adopted Values of n. Date 1814. Polar Star. Observed Values of n. Adopted Values of Date 1814. Polar Star. Observed Values of n. Adopted Values of 71. East — continued. East — continued. East — continued. § s s s S 8 Feb. 26 — 0'02 May 20 Groombr. 2180.. + 0-03 Sept. 25 Groombr. 3107.. -f-0'04 2185.. -f-0'12 3112.. -)-O')6 28 — O'O2 3359- — O'l I Mar. 27 Groombr. 1706.. + O'I2 , -I-O'OO 25 Groombr. 2180.. 2185.. + 0'02 + 0-16 + 0-09 28 3I07- 3112.. — O'O2 — O'o6 1728.. — O'OI 3359- — O'lO 28 \ -I-O'II 29 Polaris S.P — O'lO — O'lO Oct. 7 Groombr. 3082.. — O'IO 4170.. -0-13 r\< i R Apr. 3 Groombr. 1706.. +0-24 t «-.. f r June 12 Groombr. 2181.. -0-13 4 39- ^ o oo (-1. i 1 — O 10 1728.. + O'o6 "i w 4 j 2184.. + o'i6 +0-05 13 3322.. — o 4.1 — 0'22 2220.. +0-1 1 6 Groombr. 1706.. 1728.. + 0-08 +0-03 + °'°5 16 Pol. S.P. & Pol. — 0-07 — 0-07 16 Groombr. 3082.. 33"- -O'H — C'i6 242.. ^ o 14 — O'O9 23 33"- -fO'I I 8 Groombr. 1706.. 1728.. +0-17 +0-14 24 Groombr. 2165.. 2181.. -0-15 + O'O2 — O'l I 242.. — 0-12 2220.. — 0'2I Nov. 3 Groombr. 3082.. — 0'2I 9 Groombr. 1706.. 1720. + O'12 +0-09 25 Groombr. 2165.. -0'13 — O'I2 6 242.. 3082.. 242.. — O'lO -0'32 — 0'19 10 Pol. S.P. & Pol. — O'lO — O'lO 2181.. — O'lO — 0'20 9 ii — 0-09 July i Groombr. 2231.. — 0-05 12 Groombr. 143-- -0-29 2263.. — 0'02 230.. — 0-23 — O'22 >3 — 0-09 2 2231.. — o'O3 — O' I I 242.. — O'27 2263.. — 0-14 13 4094.. — o'io 17 Groombr. 1943.. — 0-08 3 2231.. — O'lO 1946.. — O'OI — o'og 2263.. —0-31 21 Groombr. 29.. —0-13 1947.. -0-17 242.. +0-03 10 to 23 — o'09 22 3778.. -0-33 — OM4 26 -0-15 29.. -OM3 24 Groombr. 2617.. — o'i7 May 7 Polaris S P — O-2I — O'2 I 26^.0. 4- O'l J. Dec. 4 Groombr. 29.. O'Oq j / 25 AWT ' 26l7.. 1 w * T -0-14 582.. -0'I5 9 Groombr. 1943.. — 0-05 2640.. +0-03 — 0*07 594- -0-13 0- I f 1 1946.. +0-04 O'OO 3° 26l7.. -0-25 603.. — O'l I U 1 *j 1947.. -|-O'O2 2640.. — o'o6 6 37/8- -0-43 29.. — O'OI 10 Groombr. 1943.. 1946. 1947" — 0-1 8 — O'O2 — O'l I — O'l 1 July 31 Aug. 3 — 0-07 — O'O2 '5 Groombr. 37/8.. 582.. 594- -0-17 — 0-03 — O'l I I '5 Polaris S.P — O'l I — O'l I 6 f 0'03 18 '9 -0-08 16 Polaris — O'lO — O'lO 8 Groombr. 3147.. 3'56- +0-13 + 0-05 20 29.. 594- — O'O2 — o'o6 18 Groombr. 2180.. 2185.. + O-IO +0-15 + O'I2 H 3'47" 3156.. + °'H — O'20 31 Groombr. 399-. 614.. — 0-32 — 0-28 -0-30 RIGHT ASCENSIONS. xxxin Adopted Right Ascensions of Stars used for the Determination of"n" in 1815, 1816, 1819. Star's Name. R.A. Appro*. J. Tan «. Authority. Star's Name. B.A. Approx. S. Tan 8. Authority. Polaris (235) 1815 m 0-55-49-47 o. 4. 28-81 . 21. 19 48 23- 53T5 .43. 14-00 -47- 3'97 .47. 27-21 .48. 6-43 2. 50. 14-00 3. 32. 48-08 3.35. 52-67 3.36. 45-05 3- 4°- 47-55 4. 6. 26-76 4. 12. 14-03 5- 56-47-57 6. 7. 17-77 6. 44. 19-43 14.27. 46-97 5- 7. 37-34 22.42. 15-13 22.47. 15-52 22.51. 24-23 88. 20 65. 1 1 71.29 71.38 70.24 70. 19 69.29 69.56 69.38 7.. 15 69.54 71. 20 72. 6  273 2-96 3-10 2-27 54 2-04 2-60 2-88 5-36  1815— continue in s 22. 54. 12-88 22.55. 1679 22. 56.37-95 22. 57. 6-58 22. 57. 59-27 59-39-53 23. 54. 12-16 23- 54- '97 3- 55- '377 23. 55- 48'42 23. 57. 52-66 1816 5.54.20-32 6. 0. 33-79 6. 0. 41-67 1819 9.47. 1-46 62. 18 62. 21 62. 24 62. 15 79-47 62. 13 69. 17 67. 51 69. 27 67- 5 68. 65.44 56.59 55.22 rgo 1-91 1-91 1-90 5'55 1-90 2-64 2'45 2-66 2-45 2-48 2'22 i-54 '•S3 -1-45 5 2 4 3 4 2 3 2 3 2 H 2 2 N Groombridge...22.. W, 1076 H 1 3077.. 11C 3080 *QQ 3082.. A22... A2O A2C A2H 4.31 ±22 I TJJ 596 727 4.22 C A2 1 C TIQ T* J> Groombridge 1076.. 742... 74.Q... 810 828 1090 I 1^6... 1108 I IOQ 124.J. i^y... Groombridge 3606 S.P... 2 I2Q 22O"  1244.. — 0-12 n Groombr. 425.. — 0-04 12 — 0-01 28 1244.. — 0-1 i 433- -0-17 Mar. 6 1244.. + 0-19 810.. — 0-18 13 Groombr. 742.. — 0-08 12 425.. - 0-08 — 0-14 749- — 0-06 f\ • I T 433- — 0-22 17 742.. -0-13 — U 1 1 Mar. 25 810.. -0-16 749- — 0-17 to Apr. 12 -f- O'lO XXXIV INTRODUCTION TO GROOMBRIDGE CATALOGUE. Determinations of "n" in 1815, 1816, 1819 — continued. Date 1815. Polar Star. Observed Values of n. Adopted Values of n. Date 1815. Polar Star. Observed Values of n. Adopted Values of n. Date 1815. Polar Star. Observed Values of n. Adopted Values of n. East — continued. East — continued. East — continued. Polaris S.P + O IO 4-O'IQ Oct. 17 Groombr. 4210.. — OM2 Dec. 1 2 Groombr. 3944.. O°33 Dec. — 1 2 Groombr. 3944.. O°33 Dec. — 0-07 24 4210.. + 0-13 H 3944- -0-41 -0-25 4221. -0-13 — 0-04. 3968.. — 0-07 26 + 0'IO 21 4210.. + 0-13 H 3944- -0-41 -0-25 4221. — 0-03 3960.. —0-42 70 Polaris 4-o-iS 4-o-iS 3Q77 — O'OC 25 Groombr. 3902.. — o'i6 j y / 1 " j May 4 4-0-19 26 3922.. 3902.. — 0-14 — 0-19 — 0-16 17 18 Groombr. 3976.. — 0*13 3976.. (-0-74) — O-2O 24 3976.. — 0'2I 7 Polaris + 0-21 4-O-21 Nov. 3 Groombr. 331.. -0-23 335- -°'34 10 Polaris -t-O'2C 4-0-21; 7 33I-- — 0-26 — 0*24 1816 -p v t. ^ 335- -0-15 East. 12 Polaris S.P + O-2I 4-0-21 15 Groombr. 421 3.. — 0-46 Jan. 14 Groombr. 1108.. 1109.. — O'l I — 0-15 I4 Polaris S.P + 0'IO 4- o-io 16 4225. 4213.. -0-39 — 0-32 18 1108.. 1 109.. + 0-07 — 0-29 — 0'12 4225.. -0-23 20 1076.. 4-0'O2 20 Polaris S.P + OM3 4-0-13 331.. — O"2 O 1108.. -0-28 335- -040 1 109.. — 0'12 22 Polaris S.P O'OO O'OO 18 Groombr. 3980.. -0-48 O' CO 28 Groombr. 1076.. 4-0'23 4*35-- -0-52 1108.. 4-°'°4 24 Grouinbr. 2129.. — 0-05 — 0-05 1 109.. 4-0-08 4-0-13 25 Groombr. 3977.- — 0-09 , 3° 1076.. 4-0-13 May 25 Groombr. 2207.. — 0-03 — 0-03 3982- — 0-04 Feb. 4 1076.. 4-0-19 26 Groombr. 3960.. — 0-09 1 1 Groombr. 1076.. — O'lO — O'lO Oct. 2 Groombr. 3922.. — 0*14 3968.. — 0'12 7 3902.. — O'll -0-15 Dec. 4 3960.. — O'02 — 0-15 21 Groombr. 1076.. — 0-04 — 0-04 3922.. — O'2O 3968.. -o'37 Feb. 23 H Groombr. 3902.. — o 07 7 Groombr. 3960.. 4-o 10 1 Q'OO to May 6 O'OO* 39"- 4-0-01 103 3968.. 4-0-03 1819 '5, — o-i i 8 Groombr. 3960.. — O'O2 East. 3968.. — O-2O l 16 Groombr. 3902.. 39" • — 0-18 — 0'22 — 0-20 9 3960.. 3968.. Groombridge. 36068. 3606 S.P. 4-0-09 4-0-07 4-0-08 As there was no material from which to derive a value of "n", the value has been adopted. RIGHT ASCENSIONS. XXXV Clock Error. The clock error cannot be described as well determined by Groombridge. He adopted thirty-six standard stars, six of which constituted a good night's determination, but more often than not there were only two or three, and as some of these stars, as Sinus, Spica, a Librae, Autares, a Capricorni, and Fomalhaut were of very different N.I.D. to that of the Catalogue stars, the effect of any error of collimation might appreciably affect the Right Ascensions. Generally speaking, the range of the clock errors deduced from separate stars was considerably larger than what would be shown by present observations. The clock errors have been deduced from a comparison of the observed transits corrected to The centre wire and for a tan $ with apparent places derived from Newcomb's Fundamental Catalogue. From a careful discussion of the results of each night's observations when reliable material was available, it was evident that an improvement in the observed places would be effected by extending the stars used for clock error so as to make them as nearly as possible of the same N.P.D. as the Catalogue stars. Accordingly, stars of N.P.D. 30° to 52° for which reliable places could be obtained, that is practically Newcomb and Bradley stars, were taken on every night on which they were observed, and the following corrections to the adopted clock errors were obtained by giving equal weights to every star, whether an original clock star or a new one. The material for such a correction extends practically only to the summer of 1810. After this date the comparison of the separate days in the ledgers indicated a few days with systematic discordances from the mean, and the corrections are given which were adopted for ten such days from 1810, Oct. 8. For this purpose the Right Ascensions of the Bradley stars for 1810 were taken from Kobold's paper, " Untersuchung der Eigenbewegungen des Auwers-Bradley-Catalogs," corrected by — 08'04 for equinox. No. of No. of No. of Date. Correctinn. Stars Date. Correction. Stars Date. Correction. Stars Clock between Clock between Clock between Stars. N.P.D. Stars. N.P.D. Stars. N.P.D. 1806. 1 1806. s 1806. s June 12 + •06 5 4 July 1 6 + •14 2 4 Oct. 6 2 5 '4 + 'IO 2 3 '7 + '15 3 9 9 -•06 3 5 'S + •13 3 7 28 -•06 3 6 10 -•'4 2 4 22 + •10 4 7 3' — '12 2 4 Nov. 8 -•05 4 <3 23 — •06 2 4 Aug. 1 1 -•07 2 3 9 -•07 2 6 28 + •08 3 4 is + •06 •7 10 10 + •08 I i July 5 -•09 i 7 22 + •10 3 1 1 12 -''4 I 3 7 + •09 3 3 Sept. 6 -r'o6 7 10 20 + •06 2 9 10 + •10 2 4 7 -•05 6 5 29 + 05 4 6 '4 +''5 2 4 26 + •06 6 1 1 3° + •08 i 3 XXXVI INTRODUCTION TO GROOMBRIDGE CATALOGUE. Date. Correction. No. of Date. Correction. No. of Date. Correction. No. of Clock Stars. Stars between N.P.D. 30°- 5 2°. Clock Stars. Stars between N.P.D. 3°°-52° Stars Clock between Stars. N.P.D. 3°°-5z°- 1806. s 1808. a 1808. 8 Dec. 3 + •16 I 2 Jan. 1 3 -•08 2 3 Nov. 2 1 — '22 3 5 1 1 -•05 8 5 22 + •08 2 i Dec. 4 -'13 6 7 24 -•19 6 10 28 + -05 2 4 16 -•32 4 1 1 25 -'13 5 13 Feb. 4 -•07 3 10 18 + •08 3 2 29 -•08 3 3 7 + -05 3 3 10 — •io 3 4 1809. 1807. Jan. 1 1 — '12 4 3 Jan. 3 — 'i i 4 8 21 -•06 4 1 1 17 -•07 2 4 18 -•05 6 3 Mar. 3 -•23 3 4 Feb. 4 + '12 4 12 25 -•19 3 6 16 -•13 5 6 13 + •16 3 5 Feb. 23 — -10 6 3 28 -•17 6 3 '7 +•09 3 3 28 -•14 4 2 Apr. 3 -•05 7 5 18 —06 4 9 Mar. 14 -•16 i I '3 -•05 6 7 26 -•07 5 10 '5 -•09 4 5 '5 -•08 2 3 27 -•08 5 10 '5 -•09 4 5 '5 -•08 2 3 27 -•08 5 10 20 +'07 3 4 21 +•10 4 7 Mar. 1 2 -•05 5 6 23 + '06 2 2 25 + '19 3 5 26 -•'4 4 '3 Apr 6 -•06 4 7 May i + -°5 6 5 Apr. i — '21 4 '4 9 -•14 3 5 4 -•05 4 i 7 -•08 4 i7 13 + •09 4 2 9 -•09 4 2 9 -•05 i 2 25 + •20 3 5 '5 — •12 2 2 15 -'05 } 11 27 + •10 3 2 '9 + •08 2 I '9 + •09 3 '9 28 + •26 2 4 21 + •12 3 3 May i — '20 2 2 May 1 1 + -05 2 3 23 + •16 4 4 3 + •06 3 12 '7 + •21 3 2 3' +•26 i 6 -M7 5 16 21 + •07 4 June 3 -•09 5 IO 22 + •09 I 2 26 -•05 4 6 4 -T9 4 7 July 6 — MI 2 I July 1 + •07 4 3 7 -•»5 4 8 12 -•07 3 6 13 + •08 4 3 ii + •12 I 2 31 -•18 2 4 15 — •10 4 4 17 — •12 3 4 Aug. xxxvii No. of No. of No. of Date. Correction. Clock Star* between Date. Correction. Clock Stars between Date. Correction. Stars Clock between Stan. N;p.a Stars. N.P.D. Stars. N.P.D. 1809. 8 1810. s 1811. , Oct. 1 5 — •11 5 7 Feb. 16 --27 i 2 Mar. 1 3 -•14 4 H 23 — '12 3 5 21 + -2O 3 8 June 8 + •18 3 16 27 -•16 4 6 23 -•07 i 2 3° — •06 2 i Mar. 1 2 -'34 0 5 1812. 3' -•'3 * 3 '7 -•05 2 7 Jan. 26 + •'4 5 19 Nov. 27 + •13 1 i 18 + •07 4 9 Oct. 3 + '22 3 7 Dec. i — •i i 2 4 20 -•'4 3 15 10 30 + •08 +•08 3 3 6 7 Apr. 4 H -•05 -36 3 '3 15 1813. Oct. * 9 + •'9 3 '4 1810. Jan. i -•06 i '5 20 25 — •06 4 + •08 i 9 12 Nov. i Deo. 12 — •22 + '24 2 3 24 '9 '4 — '20 2 16 May 8 -•07 3 5 '5 17 + •23 -•06 3 18 8 July 7 + •15 3 24 1814. Oct. 1 6 -•14 3 12 Feb. 4 -•16 3. 16 Oct. 8 + •29 4 23 23 + -I9 a >3 o/* Groombridge's Clock Stars. Name of Star. Assumed R.A. 1810. Annual Variation 1810. Secular Variation 1810. Name of Star. Assumed R.A.  + -OI54 + •0023  proper motions have been used. These stars are marked with an asterisk in the ledgers, and a list of the proper motions so used will be found under the section Ledger, pp. xlii.-xliv. V.— NOETH POLAR DISTANCES. The North Polar Distances are deduced from the microscope-micrometer readings as given by Groombridge in The Book of Zenith Distances by taking the simple mean and adding corrections for refaction, polar point, and star corrections. The material for the polar points is uniform throughout, and though it is much more abundant up to the middle of 1810 than for the remaining period, it may be considered as sufficient throughout, a fact which makes the North Polar Distances homogeneous. The chief difficulty felt in dealing with them has been as to what to do with discordant results. Owing to the fact that the figures set down for the individual microscope readings could not have been always the original readings of the micrometer heads, and that Groombridge was known to have manipulated The original readings by certain calculations which are not known, it was considered best to bracket discordant observations rather than make what appeared to be probable corrections. The computations have been carried to two places of decimals. Refraction. The refractions have been computed from the Pulkowa Tables for the readings of the barometer and thermometer given by Groombridge, the readings of the exterior thermometer when available being always used. As these readings were not very frequent, interpolations when advisable were made. Polar Points. These were obtained by comparing the observed zenith distances corrected for refraction and division error with the places derived from Newcomb's Fundamental Catalogue reduced to apparent place with star corrections deduced from Struve's tables referred to above. The observations of these fundamental stars were not kept for place, unless there were at least four. Division Errors. As most of the Newcomb stars were observed by Groombridge between the years 1806-1810, a comparison of the resulting N.P.D.'s from this period was made, the result of which was to show that there were considerable systematic errors, which ranged themselves in order when grouped according to N.P.D. and the position of the instrument. NORTH POLAR DISTANCES. The original computation had been made on the assumption that six Newcomb stars would give a good result for the polar point, but in view of these systematic differences, a recomputation of the polar points was made on all days on which there were at least ten Newcomb stars extending over an arc of 30° of N.P.D. Corresponding corrections having been applied for these new polar points, a fresh comparison was made with Newcomb's adopted places, and these new differences grouped according to the position of the instrument for every degree of N.P.D. As the instrument was reversible and there were two circles, the two positions of the instrument gave independent corrections for the same distances from the zenith, that is, covering the arc 25° to 51° of N.P.D. From the pole to 25° for the first ten degrees there was not sufficient material to give any reliable corrections, and from 11° to 25° the corrections could only be obtained from one position. Preliminary corrections thus obtained were then applied to all stars used for polar points, and the polar points were based on the use of all Newcomb stars observed on each night. The final values of the following division errors depend on the use of all Newcomb stars on all nights, and do not materially differ from the preliminary values. The following tables show the corrections for division error, and the residual errors for face east and west. The quantities for the correction to any degree depend on stars whose N.P.D. falls strictly within that degree, and the corrections have been so applied; for instance, the correction for 38° is the correction for all stars between 38° and 39°. It should also be remembered that the correction for the two circles at the same distance from the zenith in opposite directions is the same with the sign reversed; for instance, 39° East is the same as 37° West, and so on. The detailed comparison from each star will be found in the section. Comparison of Catalogues (pp. IL-lix. I. Table of Corrections  7* 37 + "47 + "S3 2 •oo •oo 20 + -01 - -48 38 •oo •oo 3 •oo •oo 21 — '12 — '42 39 - '53 - "47 4 •oo •QO 22 - -31 '34 4° - -61 - -61 5 •oo •oo 23 "4* - '59 41 ; - -50 - '55 6 •oo •oo 24 - •«> - '55 42 - '4' - '35 7 •oo •oo 25 + -13 - -04 43 - '3° + -oi 8 •oo •oo 26 •15 + -31 44 - '36 + '27 9 •oo •oo 27 - '55 + -H 45 - "37 -f- -04 10 •oo •oo 28 — -42 -o8 46 + -02 - '25 i i - '3' - ''3 29 + -03 -30 47 + "3° - '°3 12 - -31 - ''3 3° + -25 — -02 48 -f -08 + '4» '3 - "39 •38 3' - '°4 + '37 49 •24 + '55 '4 - '63 - ''34 32 - '*7 + -36 5° - '31 + '!$ '5 - -Si - 1-85 33 — -oi + '3° 5' + -04 - ''3 16 - 7° - i"95 34 + -35 + '4' 5* + "55 + -20 17 — '28 - '95 35 + '55 + "So xl INTRODUCTION TO GROOMBRIDGE CATALOGUE. Residuals of Division Errors within 13° of the Zenith, from Observation, compared with the Table, which is based on the assumption that the same Division Errors are equally applicable to both positions of the instrument at equal distances from the Zenith. N.P.D. East. T 0 West. T— 0. Observed. Tabular. Observed. Tabular. o + "•75 -"'3 -"•88 " + "04 " 26 + -oi + "5 + "H + "24 -'55 *7 + •92 + '55 -'37 - '29 - '24 + '05 28 -'45 — '03 + '42 + '66 + '3° -•36 3° - '45 -•25 + '20 + '09 + '02 - -07 31 — 'i i + '04 + "i 5 — "52 ~ '37 + "15 32 + '57 + '27 - -30 — -20 -•36 -•16 33 — 'O2 + '01 + '03 - 'H — -30 -•16 34 - '37 - '35 + '02 - '41 - '4' •oo 35 - '75 - '55 + '20 — 1-09 - '5° + '59 36 - 74 - -61 + •13 - -64 - -61 + -03 37 - '57 - '47 + '10 - '85 - '53 + '53 38 - -18 •oo + •18 — -02 •oo + -02 39  -'49 - '3° + '19 - -08 + '11 48 + '02 - '08 — '11 49 + '4 + '24 •oo - '58 -'55 + '03 5° + '31 - '34 - '28 - '5 + '3 5' — '01 - '04 - '03 + '80 + '13 -•67 Star Corrections. The remarks made under this heading in the R.A. section apply equally here. VI.— LEDGERS. The Right Ascensions and North Polar Distances, with the days of observation, entered in this section are derived from the daily results reduced by the methods described above. As the instrument was a reversible one, each face is given separately with a corresponding mean. The observations are all reduced to the epoch 1810 with the precessions and secular variations embodied in the Catalogue. In this section, the great majority of the stars are reduced without proper motion. Those stars marked with an asterisk were reduced with the proper motions given in the list pp. xlii.-xliv. No correction for division error has been applied to the results in this section. As a general rule, no hypothetical corrections have been applied to discordant motions, but observations which stand out from the mean 4" either in R.A. or N.I.D. have generally been bracketed. The number bracketed in R.A. is 75. That in N.P.D. is 214, slightly over one percent of the total number of observations. No observations of R.A. made below pole except those of Polaris have been embodied in the Catalogue places, though printed in the ledgers. They are, however, few in number. Observations of N.P.D. made below pole have been used in forming the Catalogue place of stars within 10° of the pole. Beyond 10° the observations below pole have not been used for the Catalogue place. The stars in this section are named according to the original numbering of Groombridge. Blanks are left where the original number now has no corresponding star position, and additional stars are inserted in their proper order with a small Roman letter added to the number of the preceding star. The following Nos. are blank— 805, 812, 2144, 2661, 2795, 2940, 3647, 3932, 4018. The following are additional stars — 2661a, 26616, 3192a, 3320a, 4171«. The star called 331 la in the ledgers is restored in the Catalogue section to its original No., 3297. The mean places of the following stars are considered discordant, and have not been used in the section of proper motions. In R.A. In N.P.D. In N.P.D. Groombr. 5 1 9 Groombr. i o Groombr. 1049 9°3 5' 1366 2879 39' 1637 *947 575. 1818 33110 654 3454 349' 873 349' 3604 ,, 900 3583 9°3 4'H „ 1OO2 4'*9 xlii INTRODUCTION TO GROOMBRIDGE CATALOGUE. List of Proper Motions used in Ledgers. Groom- bridge No. P.M. in R.A. P.M. in N.P.D. Groom- bridge No? P.M. in R.A. P M. in N.P.D. Groom- bridge No. P.M. in R.A. P.M. in N.P.O. xliii List of Proper Motions used in Ledgers — continued. Groom- lirirtire No. T.M. in R.A. I'.M. in N.P.D. Grooni- briilee No. P.M. in B.A. P.M. in N.P.D. Groom- bridge No. P.M. in R.A. P.M. in N.P.D. +0-0134 + 0-0028 2898 + 0-0973 2001 — 0-0024 + 0-023 2373 — 0-0206 -0-278 2900 + 0-0129 — 0-056 2905 + Q-0012 — 0-056 2905 + Q-0012 — 0-042 2014 + 0-0074 + O-0014 2414 — 0-0114 2932 + 0-0046 -0-043 2O15 -0-0134 — 0-0114 2415 — 0-0044 + 0-027 2958 — 0-0013 + 0-0014 2417 — 0-0014 + 0-0014 2428 — 0-0014 — 0-0014 2429 — 0-0014 — 0-0014 2430 — 0-0014 — 0-0014 2431 — 0-0014 2432 — 0-0014 — 0-0014 2432 — 0-0014 2434 — 0-0014 2436 — 0-0014 2437 — 0-0014 2438 — 0-0014 2440 — 0-0014 2441 — 0-0014 2442 —  0-0014 2452 — 0-0014 2453 — 0-0014 2454 — 0-0014 2454 — 0-0014 2455 — 0-0014 2456 — 0-0014 2457 — 0-0014 2458 — 0-0014 2458 0-046  10 -0-0275 + 0-403 2474 + 0-0066 — 0-016 3>49 — 0-0001 O'OOO 2II5 — 0-0328 + 0-067 2475 — 0-0006 + 0-268 3186 + 0-0067 -0-045 21 16 + 0-0108 + 0-200 2477 — O'OOOS + 0-278 3201 O'OOOS — 0-007 2I2O — 0-0106 — 0-146 2479 + 0-0002 -0-057 3210 + 0-0014 + 0-040 2125 -0-0075 — O-Olg 2488 + 0-0149 -0-075 3218 + 0-0046 + 0-018 21 30 + 0-0013 — 0-026 2492 — O'OOI8 + 0-024 3241 — 0-0047 + 0-018 2501 + 0- 0135 -0-239 325' + 0-0017 + 0-0017 2152, O-O222 — 0-0022 — 0-003 3257 — 0-0003 + O'OO2 xliv INTRODUCTION TO GROOMBRIDGE CATALOGUE. 