110 
DR. S. CHAPMAN ON THE SOLAR AND LUNAR 
Table IV. (3) (a ).—Fourier Coefficients of the Lunar Diurnal Magnetic Variation, 
Deduced to the Epoch of New Moon. 
(3) Batavia. 
(a) West Declination (in Force Units). 
Season. 
Lunar 
phase. 
ct 
b\. 
a 2 . 
h. 
^3- 
b\. 
1 
- 8 
4 
10 
-24 
- 4 
_ 2 
8 
0 
2 
10 
3 
35 
-56 
2 
- 50 
- 9 
-21 
3 
57 
67 
37 
20 
- 13 
7 
- 3 
5 
Summer . . 
.< 
4 
5 
6 
11 
2 
- 4 
6 
45 
-32 
0 
19 
2 
3 
17 
3 
- 6 
- 3 
- 3 
6 
38 
55 
34 
- 10 
- 2 
- 3 
-24 
- 15 
7 
- 7 
-33 
6 
-23 
- 12 
4 
- 3 
11 
8 
- 17 
55 
29 
2 
.14 
7 
- 9 
- 15 
e 
Mean . . 
9 
18 
23 
- 15 
1 
_ 2 
- 5 
- 5 
1 
4 
-39 
- 42 
-34 
- 28 
■ 3 
- 6 
26 
2 
- 55 
-50 
- 153 
_ 2 
- 37 
- 2 
-25 
24 
3 
24 
17 
- 20 
9 
- 38 
- 9 
-28 
- 1 
Equinox. . 
4 
5 
- 28 
- 26 
51 
- 4 
- 102 
- 48 
38 
32 
- 18 
- 20 
6 
6 
-42 
-31 
3 
25 
6 
- 41 
-27 
- 95 
-13 
55 
- 15 
-37 
-21 
7 
20 
-50 
- 45 
-50 
- 14 
-30 
- 17 
- 14 
l 
8 
- 7 
- 12 
- 21 
-44 
10 
6 
-31 
- 18 
Mean . . 
r-H 
1 
- 14 
- 66 
- 8 
- 28 
to 
~ ( 
- 27 
3 
f 
1 
- 109 
-70 
-262 
59 
- 113 
112 
-21 
56 
2 
- 87 
-28 
-207 
78 
- 32 
123 
- 8 
37 
3 
- 119 
-52 
-246 
-63 
- 126 
55 
-38 
42 
Winter . . 
, ■< 
4 
- 93 
- 75 
-225 
14 
- 82 
37 
-31 
44 
5 
60 
-46 
- 256 
15 
- 118 
30 
- 4 
33 
6 
- 88 
-84 
-312 
57 
- 172 
61 
-70 
46 
7 
- 56 
- 69 
-301 
18 
- 157 
55 
-80 
32 
8 
- 126 
- 4 
-262 
30 
- 116 
61 
-27 
15 
Mean . . 
- 92 
- 54 
- 259 
26 
- 114 
67 
-35 
38 
