AT KEW OBSERVATORY, 1890 TO 1900. 
209 
distribution than the Greenwich data, and place the equinoctial maxima—which are 
prominent in both cases—somewhat later in the year. Both sets of figures make the 
spring maximum the more important. I have shown elsewhere that Mr. Maunder’s 
figures give a less accentuated annual inequality in years of many than in years of 
Table II.—Distribution of Disturbances. 
G 
Month. 
Maunder’s 
storms at 
Greenwich. 
Kew. 
Number 
of 
separate 
storms. 
Number 
of days 
disturbed. 
Mean 
range. 
Largest 
range. 
Number of disturbed days when 
range— 
Over 
60'. 
Between 
60'and 40'. 
Between 
40' and 20'. 
Under 
20'. 
January . 
12 
10 
22 
/ 
26-5 
49-2 
0 
1 
17 
4 
February . 
22 
15 
24 
36-5 
>79-0 
2 
6 
16 
0 
March . 
21 
19 
30 
34-0 
85-6 
3 
4 
19 
4 
April . . 
12 
11 
17 
29-5 
58-0 
0 
1 
13 
3 
May . . 
14 
9 
16 
36-5 
77-4 
1 
6 
9 
0 
June 
7 
5 
6 
35-3 
40-5 
0 
2 
4 
0 
July . . 
8 
7 
10 
38-3 
77-0 
2 
2 
4 
2 
August 
12 
8 
10 
34-2 
83-2 
2 
0 
7 
i 
September. 
1G 
10 
15 
33-8 
57-7 
0 
3 
11 
i 
October 
9 
14 
25 
25-9 
35-9 
0 
0 
21 
4 
November. 
10 
10 
20 
33-3 
53-9 
0 
3 
17 
0 
December . 
7 
9 
14 
29-1 
50*3 
0 
3 
8 
3 
few sunspots. The same is true of the Kew data summarised in Table II. If we 
group the 34 disturbed days of 1890, 1899, and 1900, the years of fewest sunspots, 
and the 81 disturbed days of 1892 to 1895, the years of most sunspots, we find for 
the percentage number of occurrences in the three seasons, viz. :— 
Winter. 
Equinox. 
Summer. 
(November to February.) 
(May to August.) 
Years of sunspot minimum . . 
41 
44 
15 
„ „ maximum 
41 
34 
25 
§ 7. The Kew disturbed days were got out without any reference whatsoever to 
Mr. Maunder’s list. It seems thus worth while considering whether they afford 
support or otherwise to his conclusion that magnetic storms tend to follow one 
another at an interval of about 27-p days. Defining an “interval” as the time 
between the noons of the first days of two successive storms, the 110 intervals 
shorter than 60 days which were presented by the 125 storms at Kew were as 
follows :— 
2 E 
VOL. COVIII.—A. 
