DIURNAL VARIATIONS OF TERRESTRIAL MAGNETISM 
109 
Table IY. (2) (c).—Fourier Coefficients of the Lunar Diurnal Magnetic Variation, 
Reduced to the Epoch of New Moon. 
(2) Manila. 
(c) Vertical Force (Upwards). 
Season. 
Lunar 
phase. 
a' 1 . 
h\. 
a- 2 . 
K 
«' 3- 
b' 3 . 
a\. 
b\. 
r 
1 
4 
- 58 
-38 
- 80 
- 26 
-33 
11 
■ 2 
2 
38 
- 64 
7 
- 87 
- 3 
- 41 
0 
10 
3 
63 
- 58 
42 
79 
10 
-36 
4 
4 
Summer . . 
•- 
4 
5 
19 
9 
_ 2 
- 20 
18 
- 14 
- 94 
- 47 
37 
- 27 
-31 
-38 
- 13 
- 13 
- 6 
- 3 
6 
- 24 
94 
3 
93 
5 
- 29 
- 3 
- 1 
7 
15 
- 15 
15 
- 77 
9 
-43 
2 
- 5 
L 
8 
45 • 
68 
28 
95 
1 
- 45 
- 17 
- 4 i 
Mean. . 
20 
47 
8 
■ 81 
0 
-37 
■ 4 
i 
- 1 
r 
1 
38 
- 42 
11 
- 123 
- 9 
- 70 
- 12 
- 17 
2 
19 
- 13 
19 
- 112 
35 
-74 
14 
-23 
3 
50 
- 42 
16 
- 122 
7 
-70 
3 
- 11 
Equinox. . 
J 
* 
4 
5 
34 
_ 2 
69 
- 64 
0 
- 15 
■ 74 
- 122 
- 19 
5 
-62 
-56 
- 8 
6 
- 13 
- 23 
6 
16 
75 
10 
- 100 
10 
-52 
11 
- 13 
7 
-20 
- 43 
5 
69 
— 2 
- 55 
0 
- 19 
l 
8 
19 
37 
16 
■ 79 
4 
-32 
_ 2 
_ 2 
Mean. . 
19 
• 48 
8 
- 100 
4 
-59 
2 
- 15 
r 
1 
-80 
- 41 
-80 
46 
- 49 
- 14 
- 13 
6 
2 
-55 
16 
-93 
- 32 
■ 49 
- 13 
- 10 
- 10 
3 
-44 
• 48 
-62 
- 75 
- 41 
-30 
- 6 
- 7 
Winter . . 
•• 
4 
66 
12 
-63 
- 45 
- 32 
- 7 
- 19 
1 
5 
-58 
- 43 
-47 
• 85 
- 24 
-44 
- 5 
- 15 
6 
-25 
- 58 
-74 
- 109 
• 40 
-61 
- 14 
- 16 
7 
8 
- 22 
-29 
- 97 
- 30 
-42 
- 14 
- 7 
- 
8 
-21 
- 124 
-75 
- 112 
50 
- 47 
- 9 
- 13 
Mean. . 
-26 
42 
-65 
73 
- 39 
- 32 
- 11 
- 9 
