374 Messrs. Milne and Gray's Experiments 



From this table we see that during the six winter months 

 (beginning with October) there has been a total of 182 shocks, 

 while during the remaining six months only 123 shocks have 

 been recorded. This result, it will be observed, accords with 

 the general result obtained by Mallet from an examina- 

 tion of the earthquake records of many countries. These 

 shocks, however, were destructive; whilst those we speak of, 

 with the exception perhaps of one or two, were so small that 

 they would not have found a place in the records examined by 

 Mallet. 



Not only do we experience a greater number of shakings in 

 the cold months, but they are of greater intensities as compared 

 with those of the warm months. The intensities of the former 

 period may be denoted by 20, and those of the latter by 11. 



Prof. W. S. Chaplin has published a critical examination of 

 these earthquakes with regard to the connexion between the 

 time of their occurrence and the position of the moon. The 

 results obtained did not show any of the connexion observed 

 by M. Perrey. 



If we turn to the destructive earthquakes of Japan, we see 

 from the following Table (which is drawn up in the same 

 manner as those compiled by Mallet) that there have been 

 more shocks during the summer than during the winter. This 

 result, it will be observed, is not in accordance with the results 

 obtained by an examination of the recent earthquakes, nor with 

 the general result deduced by Mallet for the earthquakes of 

 the world. 



The table has been compiled from Japanese earthquake 

 literature. Of this literature we are acquainted with 65 books 

 treating on earthquakes, 7 of which are earthquake calendars 

 and 23 are earthquake monographs. No doubt there are many 

 other books besides those we here refer to. 



These earthquakes, examined as a whole, do not show any 

 decided decrease in seismic activity. If, however, we select 

 a particular seismic district — as, for instance, that of Kioto, 

 for which we have a series of records extending over about 

 1200 years — a decrease in the activity of that region is ob- 

 servable. If a similar examination could be made for special 

 seismic areas in Europe, instead of an examination of the 

 earthquakes of a country, we are inclined to think that similar 

 results might possibly be arrived at. 



The fact that there is not a general decrease to be observed 

 in the number of earthquakes in many countries when taken 

 altogether may perhaps be, as it is in Japan, due to the fact 

 that the earthquakes in certain areas have only been recorded 

 during a short period, and hence there is an apparent increase 

 in late years. In searching for a decrease, such as we have 

 found to exist (providing our calendars are correct) in the 



