ON EARTHQUAKES, 1925-1930 231 
700— 
600— 
500— 
400— 
300— 
J F M A M J J A $s o N D 
Fic. 1.—Total number of Earthquakes in 1918-30 occurring in various months. 
1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 1928 1929 1930 
140— S 
130— 
120— 
100— 
10— 
Fic. 2.—Number of Earthquakes occurring in maximum and minimum months, 
We 
