SUNSPOTS AND BRITISH WEATHER. 
241 
measure, do away with local peculiarities, and have a fair idea 
presented of the general rainfall and temperature over the 
kingdom. The eleven-year cycle, which we find embraced by 
the fourteen years quoted in the pamphlet,, runs from 1867 to 
1877, and the following is the relative number of Sunspots ac- 
cording to Wolff in this period : — 
1867 ..... 
. 8-8 
per cent.. 
1868 
.. 36-8 
>}> 
1869 
. 78-6 
V? 
1870 
. 131-8 
7T 
1871 
. 113-8 
)>: 
1872 
. 99-7 
}) 
1873 
. 67-7 
if 
1874 
. 43-1 
1875 
. 18-9 
1876 
. 11-3 
))■ 
1877 
. 7-0 
)} 
It will be noticed that the relative number of Sunspots rises 
from a very small number in 1867 to a very considerable one in 
1870, and then decreases again to about the original figure by 
1877. The increase is, however, much more rapid than the 
decrease, and it has been proved by Mr. Meldrum that the 
epoch of maximum number of Sunspots occurs on the average 
about four years after the epoch ©f minimum,, and the epoch of 
minimum about seven years after the epoch of maximum num- 
ber. So that though the cycle is one of eleven years, yet that 
period is not divided into two equal parts, during one of which 
a regular annual increment occurs, and during the other an 
equally regular decrement ; but into a period of four years of 
increment and seven of decrement. In the cycle under dis- 
cussion, the epochs of maximum and minimum number of Sun- 
spots are fortunately more strongly marked than they have been 
at any time during the past fifty years, so that if the actual 
number of Sunspots have any decided effect on our weather, the 
results should be more strongly accentuated during these years 
than at any other time. The following figures show the mean 
rainfall of the British Isles, divided into eastern and western 
divisions, and for the Islands as a whole : — 
East. 
West. 
British Isles 
generally. 
1866 
34-8 
46-9 
40-3 
1867 
31-2 
41-0 
36-0 
1868 
33-2 
44-4 
38-3 
1869 
32-5 
42-4 
37-0 
1870 
25-6 
35-3 
30-0 
1871 
29-4 
39-7 
34-1 
1872 
41-8 
58-0 
49-2 
NEW SERIES, V OI/. 
IV. NO. XV. 
R 
