244 
DR. C. CHREE: DISCUSSION OF KEW MAGNETIC DATA 
minimum near midwinter and a maximum near midsummer. c 3 and c 4 also exhibit 
a minimum near midwinter, but there is a second minimum—which in the case of c 3 in 
Table XXIII. — Vertical Force. (Unit ly.) 
Cl. 
C-2 . 
Os- 
C-i. 
Month. 
S. 
mini¬ 
mum. 
11 
years. 
S. 
maxi¬ 
mum. 
S, 
mini¬ 
mum. 
11 
years. 
S. 
maxi¬ 
mum. 
S. 
mini¬ 
mum. 
11 
years. 
S. 
maxi¬ 
mum. 
S. 
mini¬ 
mum. 
11 
years. 
S. 
maxi¬ 
mum. 
January . . . 
2-72 
3-53 
4-39 
1-10 
1 -32 
1-70 
0-51 
0-57 
0-71 
0-28 
0-44 
0-54 
February. . . 
3-88 
5-01 
5-98 
1-94 
2-72 
3-29 
1-03 
1-31 
1-58 
0-36 
0-47 
0-63 
March .... 
5-70 
7-03 
7-26 
4-21 
5-37 
6-24 
2-17 
2-44 
2-78 
0-94 
0-98 
1-04 
April. 
7-81 
8-39 
8-50 
5-38 
6-49 
7-47 
2-24 
2-75 
3-03 
0-70 
0-82 
0-87 
May. 
9-28 
10-88 
12-18 
6-02 
7-62 
9-26 
1-93 
2-10 
2-25 
0-52 
0-63 
0-60 
June. 
8-49 
10-33 
11-49 
5-28 
6-65 
8-22 
1-27 
1-42 
1-80 
0-47 
0-36 
0-32 
July. 
8-76 
11-07 
13-54 
5-12 
6-38 
7-55 
1-40 
1-66 
2-01 
0-43 
0-37 
0-37 
August. . . . 
5-61 
7.37 
7-78 
5-27 
6-21 
6-75 
2-05 
2-47 
2-89 
0-62 
0-62 
0-64 
September . . 
5-89 
7-64 
8-35 
3-90 
4-86 
5-34 
1-96 
2-07 
2-25 
0-85 
0-81 
0-91 
October . . . 
3-90 
5-78 
7-27 
2-07 
3-49 
4-17 
1-59 
1-89 
2-29 
0-86 
1-04 
1-18 
November . . 
3-08 
4-47 
5-32 
1-61 
2-11 
2-64 
0-74 
1-00 
1-32 
0-61 
0-68 
0-80 
December . . 
1-79 
2-95 
4-02 
0-88 
1-26 
1-78 
0-53 
0-78 
1-06 
o-io 
0-21 
0-41 
Arithmetic "1 
means . J 
5-58 
7-04 
8-01 
3-56 
4-54 
5-37 
1-45 
1-70 
2-00 
0-56 
0-62 
0-69 
Table XXI. is actually the principal minimum—near midsummer. The largest values 
in c 3 and c 4 present themselves in equinoctial months. 
Table XXIV.—Vertical Force. Phase Angles referred to Local Mean Time. 
CCi. 
OCo. 
o s . 
a 4 . 
Month. 
S. 
mini¬ 
mum. 
11 
years. 
S. 
maxi¬ 
mum. 
S. 
mini¬ 
mum. 
11 
years. 
S. 
maxi¬ 
mum. 
S. 
mini¬ 
mum. 
11 
years. 
S. 
maxi¬ 
mum. 
S. 
mini¬ 
mum. 
ii 
years. 
S. 
maxi¬ 
mum. 
January . . . 
o 
164-1 
o 
160-8 
o 
157-9 
o 
287-9 
o 
283-4 
275-0 
145 
o 
118 
o 
101 
267 
o 
277 
o 
281 
February . . 
154-6 
155-7 
154-5 
269-8 
275-9 
278-1 
104 
100 
98 
237 
261 
282 
March .... 
133-3 
143-9 
150-3 
272-7 
270-7 
268-6 
94 
93 
87 
268 
275 
282 
April. 
121-8 
130-5 
132-1 
265-4 
263-3 
260-3 
95 
94 
92 
293 
300 
298 
May. 
126-9 
129-3 
129-5 
274-9 
270 • 3 
268-4 
103 
102 
99 
302 
314 
327 
June. 
136-2 
139-5 
140-9 
271-2 
268-9 
268-3 
107 
100 
98 
307 
315 
307 
July . 
145-2 
142-8 
146-3 
266-3 
263 • 6 
262-7 
91 
82 
78 
260 
245 
219 
August. . . . 
128-8 
134-5 
136-3 
276-8 
273-5 
273-5 
104 
102 
101 
285 
280 
281 
September . . 
139-4 
143-1 
145-3 
279-4 
276-6 
277-7 
116 
109 
108 
290 
297 
298 
October . . . 
141-7 
149-5 
153-6 
267-2 
269-5 
267-6 
102 
102 
95 
281 
287 
284 
November . : 
170-4 
171-8 
174-6 
308-7 
297 • 1 
292-5 
138 
125 
108 
302 
286 
278 
December . . 
143-0 
155-9 
163-7 
281 -2 
274-3 
269-4 
125 
119 
120 
306 
267 
269 
