﻿34 TWIN-EARTHQUAKES. [Feb. I905, 



faults were almost certainly due to Caledonian movement acting 

 from north-west to south-east. Charnian movement along the same 

 lines would be more likely to produce single earthquakes. In 

 conclusion, he read the following extract from a letter which he 

 had received from the Author : — 



'Having spent the greater part of my leisure-time during the last sixteen 

 years in the study of recent British earthquakes, I propose now to continue my 

 enquiry backward, so as to include all known earthquakes in this country, my 

 objects being to determine as far as possible the distribution of seismic activity 

 in space and time, and to investigate the laws according to which faults grow. 



' I am aware that to recover more than the scantiest data regarding long- 

 past earthquakes is now an almost-impossible task, but an attempt to collect 

 and preserve what is already known seems to me worth making. If any Fellow 

 of the Geological Society should be able and willing to aid me in this work, to 

 however small an extent, or induce others to do so, I need not say how welcome 

 such help would be. 



' The most useful notes would be those relating to earthquakes before the 

 year 1891, and especially to the Hereford earthquakes of October 6th, 1863, 

 and October 30th, 1868 ; the earthquakes felt in the North of England on 

 March 15th, 1869, and March 17th, 1871, and in the North-West of Scotland 

 on November 28th, 1880 ; the Colchester earthquake of April 22nd, 1884 ; and 

 the Inverness earthquakes of February 2nd, 1888, and November 15th, 1890.' 



