HORIZONTAL FORCE OF THE EARTH’S MAGNETISM. 
393 
Table 1. — Variations of Daily Mean Horizontal Force for the Solar (26-day) period 
in millionths of the whole Horizontal Force. 
Solar 
Day. 
1844. 
1845. 
Observed 
Solar. 
Corrections for Lunar 
Corrected 
Solar. 
Observed 
Solar. 
Corrections for Lunar 
Corrected 
Solar. 
Synodical. 
Tropical. 
Synodical. 
Tropical. 
1. 
+ 146 
-44 
+ 35 
+ 137 
+ 49 
+ 7 
+ 21 
+ 77 
2. 
+ 157 
-36 
+ 23 
+ 144 
-376 
-10 
+ 16 
-370 
3. 
+ 105 
— 28 
+ 13 
+ 90 
— 111 
+ 13 
-16 
-114 
4. 
+ 172 
-16 
— 8 
+ 148 
- 28 
+ 11 
-10 
- 27 
5. 
+ 66 
— 13 
-16 
+ 37 
— 12 
— 13 
— 4 
— 29 
6. 
+ 138 
— 1 
-19 
+ 118 
+ 89 
+ 6 
+ 11 
+ 106 
7- 
— 23 
+ 8 
-17 
— 32 
+ 109 
+ 6 
- 7 
+ 108 
8. 
+ 89 
+ 23 
-11 
+ 101 
+ 70 
— 31 
-19 
+ 20 
9. 
-128 
+ 29 
— 2 
-101 
+ 149 
-12 
-18 
+ 119 
10. 
— 105 
+ 32 
+ 9 
— 64 
— 281 
+ 3 
+ 1 
-277 
11. 
-214 
+ 38 
+ 11 
-165 
-307 
- 8 
- 7 
— 322 
12. 
-324 
+ 41 
+ 12 
-271 
-194 
— 8 
+ 20 
— 182 
13. 
— 318 
+ 46 
+ 6 
-266 
-157 
+ 15 
+ 17 
-125 
14. 
-259 
+ 46 
+ 4 
-209 
- 93 
+ 10 
+ 26 
- 57 
15. 
-313 
+ 45 
-14 
— 282 
- 47 
-21 
+ 25 
— 43 
16 . 
— 248 
+ 46 
-17 
-219 
+ 23 
+ 6 
+ 22 
+ 51 
17- 
-no 
+ 44 
-26 
- 92 
+ 113 
+ 17 
+ 10 
+ 140 
18. 
- 95 
+ 35 
— 35 
- 95 
+ 85 
- 3 
+ 13 
+ 100 
19. 
+ 8 
+ 21 
— 43 
- 4 
+ 167 
— 2 
— 4 
+ 161 
20. 
+ 62 
+ 13 
-38 
+ 37 
+ 269 
+ 4 
-12 
+ 261 
21. 
+ 30 
+ 2 
-23 
+ 9 
+ 214 
- 7 
— 22 
+ 185 
22. 
+ 197 
- 8 
+ 2 
+ 191 
+ 6 
- 9 
- 9 
— 12 
23. 
+ 307 
— 22 
+ 18 
+ 303 
+ 65 
+ 3 
-26 
+ 42 
24. 
+ 254 
-26 
+ 33 
+ 261 
+ 154 
— 10 
-23 
+ 121 
25. 
+ 267 
-29 
+ 31 
+ 289 
+ 49 
— 14 
— 20 
+ 15 
26. 
+ 145 
-42 
+ 35 
+ 138 
+ 15 
+ 13 
— 11 
+ 17 
Note. — The observed quantities (Tables I., II., & III.) are deduced from the means for each civil day given 
in Table xxii., Hakerstoun Observations, Edinb. Trans, vol. xviii. p. 355, and Table xvii. vol. xix. pt. 2, p. 11, 
the means being corrected for secular change at the rate of —0-73 per diem for 1844, and of —0-25 for 1845. 
The order of corrections for the different Tables was as follows : — In 1844, 1st, the lunar tropical variations 
were corrected for the solar variations, the means of the variations for each three solar days being taken as 
corresponding to the middle day before obtaining the correction ; 2nd, the solar variations were corrected for 
the lunar tropical (means of three taken) • 3rd, the solar were corrected for the lunar synodical ; 4th, the 
lunar synodical were corrected for the solar. In 1845, the 1st and 2nd as in 1844, the 3rd of 1844 was last 
in 1845. 
MDCCCLXXVI. 
