Vol. 60.] THE DERBY EARTHQUAKES OF 1903. 215 



16. The Derbt Earthquakes of March 24th and May 3rd, 1903. 

 By Charles Davison, Sc.D., F.G.S. (Head February 24th, 

 1904.) 



[Plate XIX— Map.] 



As a seismic region, Derbyshire is marked by few earthquakes, 

 though parts, and even the whole, of the county are occasionally 

 disturbed by shocks from other British centres. To find one that 

 will compare in strength with the principal subject of this paper, 

 we must go back more than a century, to November 18th, 1795, 

 when a shock was felt over a district reaching in one direction from 

 Leeds to Bristol, and in the other from Norwich to Liverpool. 

 The dimensions of the disturbed area are given by Dr. E. W. Gray, 

 F.R.S., 1 as about 165 miles from north to south, and about 

 175 miles from east to west. ' In this latter direction, or rather 

 from north-east to south-west,' he remarks, ' it may be said to 

 have reached nearly across the island.' The area disturbed cannot 

 have been less, and may have been much more, than 23,000 square 

 miles; while, if we may judge from the places where chimneys 

 were wholly or partly destroyed (Derby, Chesterfield, and Ashover), 

 the epicentre may have coincided approximately with that of the 

 principal earthquake of 1903. 



In another respect there seems to have been a close resemblance 

 between the two shocks. It is probable from Dr. Gray's account 

 (op. cit. p. 365), that the earthquake of 1795 was what I have termed 

 a ' twin '-earthquake, that it consisted of two distinct parts separated 

 by a very short interval of rest and quiet. That this was a charac- 

 teristic feature of the earthquake of 1903 was evident from the 

 earliest reports ; and, on this account, and also since the district is 

 a favourable one for such investigations, I endeavoured to make an 

 unusually-detailed study of the shock. 2 If, in so doing, I have met 

 with any measure of success, it is almost entirely owing to the 

 kindness of the very large number of correspondents who have sent 

 me reports, to the courtesy of many newspaper-editors who have 

 given a wide circulation to my inquiries, and not least to the 

 invaluable help which I have received from Sir John G. N. Alleyne, 

 Bart., Mr. H. H. Arnold-Bemrose, F.G.S., Mr. J. E. Bolton of 

 Eckington, Mr. J. Darby, Hon. Secretary of the Wolverhampton 

 Naturalists' Field-Club, Mr. T. Gledhill of Dronfield, Mr. E. O. 

 Powell, headmaster of the Grammar-School, Stafford, the Rev. C. 

 Price of Denstone College, Mr. A. H. Stokes, F.G.S., H.M. Inspector 

 of Mines, Mr. P. K. Tollit, headmaster of the Grammar-School, 

 Derby, Dr. G. S. Turpin, headmaster of the High School, Nottingham, 

 and Mr. F. W. Webb, manager of the London & North- Western 



1 Phil. Trans. Roy. Soc. vol. lxxxvi (1796) pp. 353-81. 



2 The expenses of the investigation were defrayed from a grant received 

 from the Government Research Fund. 



