and especially in Scotland. 85 



was very distinct. We have before noticed the extreme pre- 

 valence of lightning, with occasional thunder, in the west and 

 north Highlands, this winter ; but the above is the only case 

 of earthquake in the same districts which has come to our 

 knowledge." 



A few remarks may here be offered in regard to the most 

 material inferences from the foregoing notices of shocks in 

 1840 and 1841 :— 



(1.) That there was a movement of the earth's surface, seems 

 proved by the facts stated under dates 10th and 22d March 

 1841, and 26th and 30th July 1841. These indicate that the 

 ground was moved, not merely horizontally, but also verti- 

 cally from its previous position, to which, however, it im- 

 mediately returned. An undulation of the ground was in fact 

 produced. 



(2.) That in the Comrie district, these shocks emanated from 

 a point situated a little to the west of the Melville Monument. 

 At Comrie, Clathick, and Crieff, the shocks on 18th January, 

 7th April, 26th and 30th July 1840, were respectively per- 

 ceived to come from the wesL At Dalchonzie, the shock of 

 30th July was felt and seen to come from the north, sloping 

 upwards. At Dunira, the shocks on 30th July 1840 and 26th 

 November 1841, came from the NE. In Argyleshire, the 

 shock of 30th July 1840 came from the east, whilst at Aber- 

 feldy, it came from the SW. Any person acquainted with the 

 relative situation of these places, or who studies them on a 

 map, will perceive that the shocks felt at them, must have 

 emanated from the point just indicated. 



(3.) That in most cases, atmospherical phenomena accom- 

 panied the shocks. 



Explosions, or crackling sounds in the air^ are related 

 under dates 8th January 1840, 21st April and 12 th Septem- 

 ber 1841. This phenomenon is the more remarkable, as the 

 reports were, on the last of these occasions, heard at sea, and 

 were mistaken for the firing of cannon, so that they could not 

 be confounded with the subterranean noise, which also accom- 

 panies the shocks. 



Several of the shocks took place in violent hurricanes or 

 storms, as is shewn under dates 18th January and 15th Sep- 

 tember 1840. 



