104 
DR. S. CHAPMAN ON THE SOLAR AND LUNAR 
Table IV. (l) (a).* —Fourier Coefficients of the Lunar Diurnal Magnetic Variation, 
Reduced to the Epoch of New Moon. 
(1) Zi-Ka-Wei. 
(a) West Declination (in Force Units). 
Season. 
I 
Lunar 
phase. 
1 
a',. 
b\. 
Cl 2- 
b- 2 . 
1 
a' 8 . 
b' s . 
| 
, 
a 4 . 
r 
! 
b\. 
r 
1 
167 
-34 
1 
283 
- 125 
127 
- 113 
14 
-26 
2 
153 
-43 
287 ; 
2 
117 
- 30 
2 
- 3 
3 
125 
37 
235 i 
35 
112 
3 
5 
- 17 
Summer . . . < 
4 
93 
- 18 
179 
- 9 
114 
- 3 
35 
-21 
5 
65 : 
-30 
209 
- 18 
97 
- 44 
4 
- 12 
6 
181 i 
55 
270 
- 17 
116 
- 32 
11 
- 4 
7 
86 
- 5 
209 
6 
108 
0 
19 
- 3 
- 
8 
54 
5 
207 
22 
89 
- 13 
-21 
3 
Mean. . 
116 
- 4 
235 
- 13 
. 
110 
- 29 
9 
- 10 
! 
r 
1 
56 
15 
200 
- 17 
101 
- 33 
29 
-37 
2 
40 
16 
197 
- 7 
103 
- 6 
25 
- 1 
3 
48 
15 
143 
- 34 
61 
- 38 
13 
- 16 
Equinox ... - 
4 
22 
29 
113 
- 4 
98 
- 11 
24 
-28 
5 
157 
37 
165 
- 46 
78 
5 
25 
- 9 
6 
50 
72 
131 
- 2 
84 
- 20 
38 
- 16 
7 
36 
- 9 
211 
- 49 
110 
- 63 
23 
- 18 j 
- 
8 
81 
-23 
119 
- 16 
57 
5 
26 
0 i 
Mean. . 
61 
19 
160 
- 22 
86 
- 21 
25 
-16 ; 
1 
21 
-41 
- 13 
- 82 
- 22 
- 41 
23 
- 12 
2 
- 34 
49 
- 4 
- 14 
- 46 
- 15 
- 15 
- 2 
3 
- 8 
31 
- 20 
- 50 
- 19 
- 21 
8 
-28 
Winter . . . * 
4 
- 21 
- 16 
- 38 
- 39 
- 40 
- 21 
- 18 
- 2 
5 
- 49 
11 
- 30 
- 55 
- 23 
- 36 
8 
- 17 
6 
44 
- 6 
22 
- 103 
- 16 
- 55 
- 4 
-22 
7 
! - 16 
-41 
20 
- 54 
- 19 
- 27 
10 
10 
8 
56 
-24 
65 
- 96 
26 
- 44 
- 17 
-36 
Mean. . 
j 
- 1 
- 5 
0 
- 62 
- 20 
- 32 
j - 1 
- 14 
* For an explanation of Tables IV., V., and VI., cf. § 12. The unit of force in these three tables is 
10- 7 C.G.S. 
