DR. C. CHREE: SOME PHENOMENA OF SUNSPOTS AND OF 
I 10 
Tlie standard of disturbance qualifying for “ 2 ” in the present investigation is low 
compared to that adopted by Mr. Maunder as denoting a “ magnetic storm.” During 
the 11 years as a whole nearly 1 day in 8 was allotted “ 2,” while Mr. Maunder on 
the average had only about one storm—lasting some 30 hours—in 28 days. 
With the standard adopted here, the chance of the magnetic disturbance attaining 
character “ 2 ” is about twice as great for a day which follows either 27 or 28 days 
after a day of character “ 2 ” as it is for the average day of the year. 
§ 28. Table XV. gives for each year of the eleven Wolfer’s mean sunspot frequency, 
the numl)er of days of character “ 0,” “ 1,” and “ 2,” and the corresponding character 
figure for the average day, and finally the mean values of the absolute daily H and D 
ranges. The D ranges are expressed in terms of force, on the basis that a 1' change 
of declination corresponded to a force of 5’32y acting perpendicular to the magnetic 
meridian. 
Table XV.—-Results for Individual Years. 
Year. 
Wolfer’s 
sunspot 
frequency. 
Number of days of character. 
Mean 
character 
figure. 
Absolute daily range 
(unit 1-/). 
0. 
1. 
2. 
H. 
D. 
1890 
7-1 
193 
155 
17 
0-51 
44-8 
56-8 
1891 
35-6 
147 
159 
59 
0-76 
60-8 
73-2 
1892 
73-0 
129 
189 
48 
0-78 
84-0 
94-2 
1893 
84-9 
140 
191 
34 
0-71 
69-7 
83-1 
1894 
78-0 
98 
220 
47 
0-86 
81-4 
87-8 
1895 
64-0 
97 
194 
74 
0-94 
67-9 
82-9 
1896 
41-8 
132 
168 
66 
0-82 
64-5 
77-2 
1897 
26-2 
152 
167 
46 
0-71 
51-8 
64-6 
1898 
26-7 
161 
158 
46 
0-68 
56-0 
65-4 
1899 
12-1 
176 
152 
37 
0-62 
49-6 
60-3 
1900 
9-5 
274 
82 
9 
0*27 
37-3 
48-8 
Means . . . 
41-7 
154 
167 
44 
0-70 
60-7 
72-2 
-- 
As already remarked, it is difficidt to avoid sensible fluctuations in the standard of 
chaiacter figures, but the range figures support the character figures in representing 
1893 tlie year of largest sunspot frequency—-as very decidedly less disturbed than 
the two adjacent years. Again, all the criteria agree in representing 1900 as decidedly 
the quietest year, though 1890 had fewer sunspots. 
I he lange of the regular diurnal inequality was largest in the year of sunspot 
maximum. Other things being the same, the absolute range would naturally increase 
with that of the diurnal inequality. There is thus nothing surprising in the fact that 
the D and H absolute ranges in 1891, 1895, and 1896 are exceeded by those of 1893, 
though the character figure obtained for the latter year is less. Whether the character 
