236 
DR. C. CHREE: MAGNETIC DECLINATION 
months, they are omitted in Table XXII. which summarises the results of the 
investigation. 
The conclusions drawn from Table XXII. will, I suspect, depend a little on the 
temperament of the reasoner. There is a deficit of quiet days and an excess of 
disturbed days in the group of days of largest sunspot area, the excess of disturbed 
Table XXII.—Occurrences of Quiet and of Disturbed Days. 
Groups. . . 
Quiet days. 
(Number found in each group.) 
Disturbed days. 
(Number found in eacb group.) 
I. 
II. 
III. 
I. 
II. 
III. 
1890 
5 
6 
4 
0 
0 
0 
1891 
19 
18 
23 
4 
11 
6 
1892 
17 
23 
20 
8 
16 
6 
1893 
20 
16 
24 
6 
2 
3 
1894 
20 
18 
22 
10 
7 
4 
1895 
21 
21 
18 
4 
6 
9 
1896 
22 
18 
20 
15 
11 
11 
1897 
18 
22 
20 
5 
2 
7 
1898 
16 
23 
21 
8 
7 
4 
1899 
14 
21 
10 
6 
3 
8 
1900 
7 
9 
9 
2 
0 
0 
Totals . . 
179 
195 
191 
68 
65 
58 
Percentages . 
31-7 
34-5 
33-8 
35-6 
34-0 
30-4 
days being the more conspicuous. But whilst the mean from the whole 11 years 
appears favourable to a slight connection between disturbance and simultaneous 
sunspot area, there are individual years ( e.g . 1895 and 1899) which associate quiet 
days with large sunspot area, and some (1895, 1897, and 1899) which associate 
disturbances with small sunspot area. 
The mean sunspot areas for the whole 11 years were, in the Greenwich units, 1626 
from the group of largest areas, as against 312 from the group of least area. Thus 
the difference between the days of Groups I. and III. as regards sunspot area was 
very large. Taking this into account, we must, I think, conclude that the results of 
Table XXII. are incompatible with any theory which regards magnetic disturbance 
as dependent directly in any large degree on the simultaneous extent of the projected 
sunspot area. Further, even if we assume that no appreciable accidental element 
enters into the mean results of Table XXII., and that they would be reproduced in 
means derived from a whole century, it would not necessarily prove the slightest 
connection of the kind mentioned. 
