NOTES ON EARTHQUAKES. 
213 
with those of extinct animals, have been greatly altered in 
position, and upheaved since the deposition of the organic 
remains, while ancient land surfaces have in other parts sub- 
sided beneath the sea. Ancient canoes have been found near 
Glasgow, in upheaved marine silts ; and we are informed by 
Sir Charles Lyell, that “ at the time when these ancient vessels 
were navigating the waters where the city of Glasgow now 
stands, the whole of the low lands which bordered the present 
estuary of the Clyde, formed the bed of a shallow sea.” This 
emergence is proved to have been gradual and intermittent. 
On the east and west coasts of Scotland there are raised 
beaches of from twenty-five to forty feet in height above high- 
water mark ; and it appears probable that the coast-line in the 
neighbourhood of Edinburgh, has changed since the human 
epoch. At all events, it has altered considerably within a 
recent geological period. * Mr. Geikie believes that an 
elevation of other parts of the Scottish coast-line has occurred 
since the Roman occupation of the Roman stations on the 
Solway, the Forth, and the Clyde. This presumption is still 
doubtful, but my own observations and inquiries induce me to 
believe that Mr. Geikie is right. We have then a good deal 
of evidence to prove that oscillatory movements have occurred 
in England, to a very considerable extent, up to a late 
period; and I believe that such movements should be attri- 
buted to a succession of small earthquakes, such as the late 
shock so generally experienced throughout England, or those 
shocks which destroyed the cathedral of Lincoln in 1185, and 
many of the largest churches in England in September, 1275. 
I say, a succession of small earthquakes , for we have no evidence 
of the overflow of volcanic matter, or of paroxysmal earth- 
quakes, such as those which happen in volcanic countries, for 
a very long period. 
With regard to the late earthquake, it had every appearance 
of being one of those sensible vibratory undulations of the 
earth's surface, referred by Mr. Scrope (C to the snap and jar 
occasioned by a sudden and violent rupture of rock masses at 
a greater or less depth, and probably the instantaneous injec- 
tion into the fissures so formed of intumescent molten matter 
from beneath.” It certainly seems only reasonable, when we 
reflect that the British Islands are on the line of the volcanic 
belt which affected Portugal when Lisbon and several other 
cities were nearly destroyed, and which reaches to the Canary 
Islands, to refer our British earthquakes to the same cause as 
volcanic eruptions, namely, pent-up subterranean heat. We 
* See “Edinburgh and its Neighbourhood,” a work by the late Hugh 
Miller, just published. 
