368 



C. Davison — British JEartl) quakes of 1889. 



5. East Cornwall Earthquake : Oct. 7, 1889. 



Time of occurrence, about 13h. 45m.; Intensity, IV. Epicentrum, 

 about 2f miles S.W. of Altarnon. 



Disturbed Area. — All the planes, 24 in number, at wbich the 

 earthquake is recorded as having been felt, are included within an 

 area which is roughly elliptical in form. The larger axis, which 

 runs nearly east and west, is about 25 miles in length, the shorter 

 axis about 20 miles, and the whole area disturbed about 400 square 

 miles. The curve bounding this area is an isoseismal of intensity IV. 



M.ComwcdL ^arihquxike ' Oct// ISS9. 



Nature of the Shock. — The accounts of the shock, though few in 

 number, are sufficient to indicate roughly the way in which the 

 nature of the shock varied throughout the disturbed area. We may 

 divide the observations into two groups. In the first we have : 



Altarnon : a distinct rumbling was heard, as if the chimney were 

 on fire or a heavy waggon passing up the road ; very little if any 

 perceptible vibration. 



North Hill : a sound heard as though something had struck the 

 wall of the house, and " then the sound seemed to vibrate at the 

 back." 



