uo 



♦ KNOWLEDGE • 



[Oct. 20, 1882. 



•" rats or mice across tlie room," rattling of crockery-ware 

 ..a cuplxMird, "as though a cat were shaking a shelf," and 



on. Yet Ihfre the earthquake is, and it is quite possible 



•Jiat the force which actually produces the disturbance is 



■ic of tremendous energy. For it is an unsound argument 



t 1 jHjint to the cllV-cts which luay be protluced by ordinary 



;rface shocks. It is true that the fall of a building, the 



xplosion of a magazine, and even the passing of a vehicle, 



^vill sliake tlie ground. Hut the conclusion often drawn 



i:>>ni these fact.s — namely, that an earthquake may come 



f ver>- sliijht and local causes — is unsound. A shock which 



1 felt over half this island comes from no slight cause, anil 



is in no way comparable with disturbances which are e.\- 



|^?ricnced over an area of but a few miles at tlie outside, as 



•Allen a i>owder magazine exjilodes. The subterranean 



urce of these wide-spi-ead quiverings of our stable English 

 ,round are, we may be sure, dcej)seated and energetic, 

 . -.en if it underlies immediately the region in which its 

 ac:tion is frit. But if, as is probably the case, the throe is 

 propagat**! from a distant source, and comes to the surface, 

 so to speak, in our western counties, it may \)e comparable 

 i:i ener^, for auglit we know, to some of those violent 

 il.terranean heavings which liave worked the most terrible 

 L.ischief to tlie human race. 



Indeed, we have good reason for believing tliat the earth- 

 I'lakes felt in England lielong to the same system, and 

 ome from the same centre of subterranean action, as those 

 \v hich have shaken Portugal, Morocco, and Algiers, Southern 

 Italy, Tnrkey-in-Europe, and Asia Jlinor. There is a 

 I -culiarity about the British earthquakes which is well 

 \^ ortli noticing, and seems to Ije e.\plicable in no other way. 

 Thrc* hundred earthquakes and upwards liave been recorded 

 a=. having shaken these islands, and it has been found that 

 .li nearly every instance the wave of disturbance has tra- 

 \-lled in the same direction. This direction is (roughly) 

 •:om south-west to north-east, and the seat of disturbance 

 thus indicated is that submarine region between the Azores, 

 r^neritle, and the Cape Verde Islands, which is looked upon 

 x-, the principal source of the greater European eartluiuakes. 

 Precisely as the last of the great earthwaves wliicli devas- 

 tates! Peru came sweeping in from the Pacific, so the throes 

 which destroyed LislK)n in 17-'>'.» swept in from the west. 

 And though there arc other sources of di.sturbance in the 

 South-European volcanic district, yet it has been the opinion 

 of thf most eminent geologists that these all communicate 

 with the source underlying the western Atlantic, and that 

 the latter source is the most deep-seated and therefore the 

 most important of them all. 



We proceed to give a brief account of the most remark- 

 able evidences wliicli these islands have a(rorded of the 

 energy of subterranean forces, either acting immediat<'ly 

 beneath them, or propagated along deep-lying channels 

 from the far distant seat of disturbance which we have 

 indicated. 



.'^ome of tlie earlier earthquakes of which records have 

 Utn hand*-d down woidd seem, if the accounts can be 

 trustf-d, to have Ix'cn much more imjtortant than those 

 which have recently taken place. Wendover relat<-s that 

 in 07 \ the whole of England was shaken by a great earth- 

 quake ; and the earthquake of 1 08 1 was accompanied, we 

 are told, by a tremendous roaring noise — "a heavy VjcIIow- 

 ing,** as one chronicler says— which was heard throughout 

 the length and breadtli of tin; land. In the Sa.Yon chronicle 

 it is stated that there was, in )Of<I), "a mickle earth- 

 stirring over all England 1 A somewhat remarkable efl'ect 

 was axcrilied to this earthquake. It hajifiened that the 

 liarv<i,t wan verj* backward in that year, and it was sup- 

 posed that this wa« due to Uie earthquake, as though per- 

 haps the seeds had l>een shaken somewhat down from their 



original place, and had so taken a longer tiiiu' in attaining 

 maturity. 



A very singular event occurred in 1110. During the 

 occurrence of a very sharp shock of earthquake at Shrews- 

 bury, the River Trent was dried up at Nottingham "from 

 morning to tlie third hour of the day," says tlie narrator, 

 Florence of Worcester, " so that men walked dryshod 

 through its channel." 



We are now approaching a period when the most 

 remarkable earthquakes which have ever been known in 

 England were experienced. In ll.'J.S a great earthquake 

 was felt over a large part of Groat Britain. In 11G5, 

 according to JIatthew Paris, " there was an earthquake in 

 Ely, Norfolk, and Suflblk, so that it threw down men who 

 were standing, and rang the bells." In lisri, shocks were 

 felt which were so violent that Lincoln Cathedral was flung 

 down, and an immense amount of mischief was worked in 

 that and neighbouring counties. Two years later there 

 hap]iened another earthquake, in which, according to 

 Matthew Paris, many V)uildings, and some which were 

 strong and well established, were thrown down. 



If we are to believe Matthew Paris, the earthquake 

 which took place in lL'47 was attended by some very note- 

 worthy phenomena. He relates that the shock was ex- 

 perienced witli especial violence on the banks of the 

 Thames, where many buildings were flung to the ground. 

 But the singular feature of the event was that, a few days 

 after, the sea became unnaturally calm, as if the tides had 

 ceased, and so remained for about three months. It seems 

 dillicult, however, to associate the two events together in 

 any way ; and doubtless the calm of the sea, though it 

 may have been remarkable, is to bo ascribed to ordinary 

 causes. Possibly the character of the phenomenon has been 

 much exaggerated. 



In l:i4S, the western parts of England were shaken 

 with an energy far exceeding anything which has been 

 known in recent times. Wide rents were opened in the 

 churches of the diocese of Bath, and a portion of the tower 

 of Wells Cathedral was flung down and fell through tlu; 

 roof. The cathedral at St. David's was also seriously 

 damaged. 



But from all accounts, it would seem that the earth- 

 quake of September, 127.'), the last of the series of events 

 whicli beh^nged to the epoch wo have referred to above, was 

 the most remarkable of them all. Matthew of Westminster 

 relat<'S that " by the violence of this earthquake the church 

 of Saint Michael of the Hill, outside Glastonbury, fell down 

 levelled with the soil." And it is said that many of the 

 largest churches in England were destroyed or greatly 

 injured by the same shock. 



It is rather a singular circumstance that this period of 

 activity was associated with an interval during which 

 Mount Vesuvius was remarkably quiescent. After tin- 

 eruption of 10(9, ninety years pa.ssed, during which the 

 mountain was not disturbed, and then another long rest of 

 108 years. That this repose was not duo to ony inter- 

 mittencc of subterranean action is clear from the fact that 

 the volcanic district around Vesuvius was forced into un- 

 usual activity— as if an effort were made in this way to 

 compensate for the temporary cessation of the great crater's 

 activity as an outlet of discharge to the elastic fluids and 

 lava which are formed during 8ubt<!rranean disturlmnces. It 

 is related that the Solfatara I/ake was in eruption, and the 

 volcanic islanrl of Ischia, which had been at rest for 

 fourt<*ii centuries, was roused into so active a state that 

 in 1.302, aft<;r many heavings, the island gave vent to a 

 lava-stream of enonnous dimensions. I'his stream flowed 

 for a distance of two miles. 



it may seem startling to many to find earthijuakes in 



