DIURNAL VARIATIONS OF TERRESTRIAL MAGNETISM. 
33 
Table H ( b ).—Comparison of the Lunar Semi-diurnal Magnetic Variations at Five 
Observatories, as determined by van Bemmelen (l) and in this Paper (2). 
The Unit is IQ- 7 C.G.S. 
Observatory. 
West. 
North. 
Radial. 
c 2 . 
d. 2 . 
Co. 
C 2 . $2- 
1. 
2 
1. 
2. 
1. 
2 ' 
1. 
2 
1. 
2. 
1. 
9 
1 
Summer. 
Pavlovsk . . . 
Pola. 
Zi-Ka-Wei . . 
Manila .... 
Batavia. . . . 
Ill 
137 
203 
128 
14 
112 
126 
211 
134 
14 
O 
99 
94 
110 
112 
102 
o 
87 
75 
84 
99 
201 
82 
145 
31 
31 
51 
86 
115 
11 
64 
81 
o 
44 
36 
73 
199 
212 
o 
3 
26 
56 
200 
210 
21 
57 
112 
79 
38 
4 
48 
115 
88 
34 
o 
245 
164 
99 
186 
185 
O 
214 
135 
76 
167 
187 i 
Winter. 
Pavlovsk. . . 
Pola. 
Zi-Ka-Wei . . 
Manila .... 
Batavia. . . . 
15 
29 
66 
80 
178 
20 
33 
75 
80 
195 
340 
20 
148 
205 
269 
24 
357 
122 
184 
267 
45 
19 
80 
113 
77 
16 
30 
82 
115 
119 
219 
90 
114 
205 
219 
133 
68 
128 
247 
214 
15 
30 
89 
82 
13 
3 
30 
96 
92 
14 
184 
129 
90 
221 
347 
129 
67 
198 
315 
Year. 
Pavlovsk . . . 
Pola. 
Zi-Ka-Wei . . 
Manila .... 
Batavia.... 
53 
75 
129 
74 
82 
61 
68 
137 
80 
101 
92 
83 
119 
144 
267 
79 
61 
93 
128 
263 
18 
79 
53 
72 
64 
48 
70 
43 
90 
100 
35 
41 
103 
204 
216 
356 
35 
121 
196 
212 
16 
42 
101 
77 
13 
1 
38 
105 
86 
14 
220 
152 
95 
204 
193 
133 
72 
183 
210 
The comparison may be completed by giving the results of van Bemmelen’s harmonic 
analysis of the semi-diurnal part of the variation, so far as they are comparable with 
our present result. Only the annual mean values of E 3 2 ( a ), E 3 2 (b), I 3 2 (a), I 3 2 ( b ) can 
be compared in this way. They are as follows :— 
E s 2 («). 
e 3 2 (U 
b 2 («)■ 
Is 2 (U 
van Bemmelen .... 
1-2 
4-2 
0-1 
3‘5 
Present paper. 
0-3 
4-9 
1-7 
2-8 
The values in the last line are formed from those given in Table G for the mean 
solstice (weight 2) and equinoxes (weight l). The order of magnitude of the above 
„ VOL. CCXVIII.-A. E 
