Dr. C. Davison— Bntish Earthquakes, 1893-99. 175 



another, tbinking an explosion had occurred. One informed me 

 that a severe shaking was felt, the tools sprang from the floor and 

 the dnst rose in clouds off the bottom. Indeed, the shock seems to 

 have been distinctly stronger underground than on the surface. 



Kilsyth : Feb. 16, 1898.— Kilsyth lies in the valley of the Kelvin, 

 11 miles N.E. of Glasgow, and the same distance from Falkirk and 

 Stirling. The supposed earthquake occuri-ed at 1.33 p.m. It was 

 felt and heard by hundreds of people in the town, but, though 

 I have made many inquiries, I have received nothing but negative 

 records from the surrounding country. It is therefore certain that 

 the area affected must have been very small. All the accounts from 

 Kilsyth are in agreement as to the nature of the shock and sound. 

 There was a single movement, which immediately died away, 

 lasting about a second ; a dull heavy thud, as if some heavy article 

 had fallen on the ground shaking all around. It was strong enough 

 to make windows and crockery rattle, in one house to ring bells, 

 and in others to throw down crockery from the shelves. The sound, 

 which accompanied the shock, is said to have resembled the tipping 

 of a load of coals, the fall of some heavy body, the slamming of 

 a door, etc. Men working in the mines below were so alarmed that 

 they ran to the bottom of the shaft. 



Pendleton {near Manchester) : Feb. 27, 1899. — With one exception, 

 I am indebted for all the records which I possess of this supposed 

 earthquake to the kindness of Mr. Mark Stirrup, F.G.S.^ The shock 

 was felt shortly after 10 p.m., according to one observer at exactly 

 10.1 p.m. The places at which the shock was felt are all withia 

 a small area, appi'oximately circular in form, and about 4- or 5 

 miles in diameter. The centre of the area is about ^ mile north 

 of Pendleton, and lies a short distance on its downthrow side from 

 the Irwell Valley fault. Even if we disregard the evidence of some 

 observers as possibly exaggerated, there can be no doubt that the 

 intensity of the shock was not less than 4, and it may have been 

 as great as 5. A booming sound, like that of a gas explosion, 

 accompanied the shock. In the Pendleton Colliery some falls of 

 rock took place, and raised a cloud of dust which put some 

 workmen's lamps out. 



Origin of the Earth- Shakes. — There are certain features which are 

 common to all the earth-shakes here considered, and which dis- 

 tinguish them from most ordinary earthquakes. They are : — 



(1) The disturbed area is small ; in the strongest, it is not more 

 than about 5 miles in diameter. 



(2) The intensity of the shock is very great for so small an area, 

 and dies away rapidly from the centre towards the boundary. 



From these facts, we conclude that the depth of the centre of 

 disturbance is very small, and the inference is supported by the 

 obviously great intensity of the shocks as felt in mines. Again : 



(3) The shock and sound are of very short duration. The brevity 

 of the sound is strikingly illustrated by the type of comparison 



1 See a paper by Mr. Stirrup on " The Earthquake of February 27th, 1899 " : 

 Manchester Geo). Soc. Tr.ms., vol. xxti, 1899, pp. 174-178. 



