and especially/ in Scotland. 279 



noise were greater than anywhere else, and that they dimi- 

 nished with the distance from this spot ; (3.) that the shock and 

 the noise moved simultaneously in all directions, from this spot. 



If these inferences are sound, Mr Lyell has not given a cor- 

 rect representation of the earthquakes which occur in this coun- 

 try. He says, that " all countries are liable to slight tremors at 

 distant intervals of time, when some great crisis of subterranean 

 movement agitates an adjoining volcanic region. But these 

 may be considered as 7nere vibratiotis, propagated mechanically 

 through the external covering of the globe, as sounds travel 

 almost to indefinite distances through the air. Shocks of this 

 kind have been felt in England, Scotla7id^ Northern France, 

 and Germany, particularly during the Lisbon earthquake.''* 

 It is evident, from this passage, that Mr Lyell considers any 

 shocks which occur in England and Scotland, to be mere vi- 

 brations transmitted along the earth's surface from some dis- 

 tant volcanic outburst. It is true that there are, in the fore- 

 going register, cases of this description, and of which the 

 Lisbon earthquake, referred to by Mr Lyell, is one ; but it 

 must be evident, for the reasons already given, that the vast 

 majority of the shocks recorded, present phenomena totally 

 distinct from those exhibited by the Lisbon earthquake, and 

 that they are truly indigenous to this country. 



If, then (as can scarcely be doubted), most of the shocks re- 

 corded in the foregoing register have their sources in this 

 country, it becomes an object of interest to discover where 

 these sources are, and whether they lie deep in the globe. 



It bears strongly on this point to observe, that, out of 139 

 shocks in Scotland, there were 85 which emanated from 

 Stratherne, and apparently near Comrie ; and that 23 ema- 

 nated from the Great Glen or its vicinity. In England, out of 

 the 116 shocks recorded as having there occurred, 31 origi- 

 nated in Wales, 31 along the south coast of England, 14 in the 

 borders of Yorkshire and Derbyshire, and 5 or 6 in Cumber- 

 land. 



These facts seem to shew that the seat of action cannot 

 be very far down in the earth's interior, otherwise the effects, 



* LyelPs Principles, vol. ij. p. 59 (fifth edition^. 



