282 Mr D. Milne oh Earthquake- Shocks in Great Britahii 



ricii, was> at 8 p.m. on the same clay (reckoning by the clocks 

 there), visited by a severe shock, which lasted half a minute. 

 It is very probable tliat to the list nov*^ presented other 

 cases might be added, in which shocks of earthquake oc- 

 curred in this and some distant country about the same time. 

 Some of these cases evidently indicate nothing more than the 

 vibration communicated by one single concussion to adjoining 

 regions, as in the case of the celebrated Lisbon earthquake. 

 The fifth example in the above list, evidently belongs to this 

 class, and it is probable that there are several others. 



The cases about which any question can arise, are those 

 where two distant parts of the globe are agitated at the same 

 moment, without any appearance of a commotion in the inter- 

 vening region. That such a subterranean connection may 

 exist, is placed beyond doubt by the account which Humboldt 

 has given of the eruptions in South America. He relates an 

 instance where a volcanic mountain, which had for time im- 

 memorial emitted smoke, ceased to do so at the vei-y moment 

 that a terrible earthquake occurred in a distant part of that 

 extensive continent. Without denying, then, the possibility/ of 

 a connection existing between the sources of British earth- 

 quakes and those in foreign countries (as in Calabria), it is the 

 evidence that such a connection does exist which is deside- 

 rated. The only circumstance founded on to prove this, is 

 the occurrence of the shocks in these dista^nt regions, on one 

 and the same dai/. But it should be recollected that in Cala- 

 bria, Sicily, South America, and many other countries, earth- 

 quake-shocks occur almost every month, and occasionally for 

 days and weeks continuously ; so that, in such cases, it is very 

 possible that on the same day, nay, at the same hour, that 

 shocks are felt in this country, shocks should be going on in 

 other regions, without there being the least connection between 

 the several series. 



But insufficient as is the coincidence of time to form, of itself, 

 a proof of connection between the shocks indigenous to this 

 country and those which occur abroad, even this element is 

 awanting in all the cases which have been suggested. It has 

 never been shewn that the shocks coincide more closely than 



