56 REPORTS ON THE STATE OF SCIENCE. 



have resulted in adjustments in the earth's crust of geological import- 

 ance. Taken in groups they indicate marked periods in the relief of 

 seismic strain. 



As an incentive to continue this new type of register, although in 

 1908 but a small portion of it had been completed, I called attention to 

 the fact that it showed : — 



First, that about 1650 there had been a period of marked seismic and 

 volcanic activity in the world. 



Second, that although the periods of seismic activity in Italy and 

 Japan were each separated by irregular intervals of time, the years in 

 which there had been marked activity in one of these countries closely 

 corresponded with the years when there had been marked activity in the 

 other. Should further analyses confirm this conclusion, the suggestion 

 is that the relief of seismic strain in one part of the world brings about 

 relief in some other part, or that relief is governed by some general 

 internal or external agency. 



The first entry in the catalogue is a.d. 1, and they are continued to 

 a.d. 1900. This portion of the catalogue, which I propose to issue as 

 Part I., will contain about four thousand entries. 



I recognise its incompleteness, and trust that the lacuna will 

 shortly be filled up and brought together as a supplement. 



When examining this catalogue it must be remembered that it only 

 refers to disturbances which have originated on land surfaces and along 

 seaboards. Further, it must be borne in mind that the historical records 

 of different countries extend over very different periods of time. 



The sources from which materials have been drawn are briefly as 

 follow: — 



"Well-known catalogues like those of Mallet, Perry, and Fuchs have 

 formed a foundation. Next came Japanese catalogues of earthquakes, 

 together with abstracts from records published in China ; in these much 

 information is given not obtainable elsewhere. The translations of the 

 latter made by Mr. S. Hirota and Professor E. H. Parker were particu- 

 larly difficult. In the former of these (see Report 1908) certain slight 

 errors have been found in the materials from which the translations 

 were made. For dates between a.d. 46 and a.d. 194 one or two days 

 should be added, while for dates between a.d. 200 and a.d. 1590 three 

 to ten days should be subtracted. The resulting dates are for the most 

 part those on which earthquakes were notified, and not necessarily those 

 on which they occurred. Numerous lists and monographs on the 

 earthquakes of particular countries have been translated. Three of 

 these accompany this Report. Many documents were obtained from 

 various parts of the world where Great Britain is represented, by the 

 kind co-operation of the Foreign, Colonial, and India Offices. Much 

 time was spent, but, I regret to say, not very profitably, in examining 

 the files of our more important newspapers and periodicals. Better 

 results came from foreign journals and the publications of learned 

 societies. These and other references to sources of information will be 

 detailed in the catalogue, 



