May 23, 1872] 



NATURE 



61 



counties of England " (Memoirs of the Geological Survey of 

 Great Britain, vol. i. p. 297) ; Dupont's " Essai d'une Carte 

 <^eologique des Environs de Dinann" (DuUe in de 1' Academic 

 Royale de Bruxelles, vol. xx. pp. 9 and 10) ; Reunion Extra- 

 ordinaire de la Socictc Geologique de France a Liege (Bulletin 

 de la Socicte Geologique, 2 sen, vol. xx. p. 761) ; Elie de 

 licaumont's and Dufienoy's Explication de la Carte Geologique 

 de la I'^rance, vol. i. jjp. 240-64 ; also to Lyell's Elementary 

 Manualof Geology, ai tide, "Deauditioii ;" and toDela Bsche's 

 'Geological Ob erve," p. 815. 

 Shorehatn, Kent, May 18 Joseph Prestwich 



VOLCANOES AND EARTHQUAKES 

 'HP HE remarkable series of volcanic phenomena which 

 -'- have lately been exhibited at various parts of the 

 earth's surface within so short a period of time, gives much 

 matter for consideration, and must iu due time aflbrd us 

 a rich harvest of facts with which to test the numerous 

 theories which have been started to account for the oc- 

 ctirrence of volcanic eruptions and of earthquakes. Even 

 from our at present scanty information we have, I think, 

 sjmething to learn. 



First in the series, so far as I am aware, was the very 

 severe earthquake at Independence, Inyo County, Cali- 

 fornia, which took place on Tuesday, March 26, com- 

 mencing at 2 A..M., and lasting till 7 A.^r., during which 

 time " the earth was never for a moment perfectly quiet, 

 and every few minutes heavy shocks, of a few seconds' 

 duration, were occurring ; in all there were more than 

 fifty \ery heavy shocks." This place is only fourteen 

 miles from the Black Rock, a volcano in the Sierra 

 Nevada mountains, " the sides of .which are covered with 

 lava, and which is supposed to be an extinct volcano." It 

 is stated that '■ during the time the shocks were most 

 severe, flashes of light were seen to issue from the top of 

 this mountain, and streams of fire ran down its sides." 



The result of this earthquake is summed up in a few 

 wordsas " thewholecountry turned topsy-turvy" {I'irs^inia 

 City (Nevada) Enterfirisc). 



'rhen a few days afterwards came the terrific earthquake 

 in Antioch, which commenced on April 3, and continued 

 witli greater or less severity, ''in Aleppo, and as far east 

 as Orfi, beyond the Euphrates," for more than a week, 

 becoming very severe on April 10 ; here there appears to 

 have been no actual volcanic phenomenon ; but it appears 

 from the letters of the Rev. W. Brown in the Times, that 

 there exists in the immediate neighbourhood a mountain, 

 '■the pecu'iar conical form of which is very suggestive of 

 an ancient volcano." 



The latest African news tells us that " Several violent 

 shocks of earthquake had occurred at Accra, on the (lOld 

 Coast, on April 14 and 15, causing considerable damage 

 to the place." And as unwonted atmospheric disturb- 

 ances have often been connected with volcanic phenomena, 

 it may not be out of place to mention here the feaiful 

 hurricane which wrecked every vessel but one in the 

 Harbour of Zanzibar on April 15. 



And then on April 24 began the recent eruption of 

 'Vesuvius, which will be for ever memorable, not only 

 on account of its magniiude and grandeur, but also, 

 and stdl most so, by reason of the amazing intrepidity 

 o' the mau, who, from a pure love of science, remained 

 at his post, like the gatekeeper of Pompeii, throughout 

 the whole of that terrible time, but happily was not, 

 like that heroic soldier, buried in a shower of ashes ; 

 the world was spared the loss. 



Now is there any connection between these pheno- 

 mena exhibited in so distant parts of the earth's surface ? 

 One thing is certain, namely, that within the short 

 space of a month all this has occurred, and one can 

 hardly help thinking that somehow or other these vol- 

 canic countries must be connected underground ; it has 

 long been thought that Etna and 'Vesuvius are points 

 on a volcanic area which passes north-west to the 



Eifel, Auvergne, and Iceland ; has the neighbourhood of 

 Antioch, with its unenviable notoriety for earthquakes, 

 or the West African coast, anything to do with this 

 area ? But if so, what shall we say of the Sierra 

 Nevada, why should its volcanoes be active at the same 

 time ? Why should the country there be " turned topsy- 

 turvy" by earthquakes 1 



While pointing out these coincidences, we must not 

 jump too hastily to conclusions from them ; for on 

 the one hand we are told that although the Antioch earth- 

 quake extended so far east, yet, to the north and south, 

 even at a few miles' distance, nothing whatever was ob- 

 served, and, on the other hand, that the Californian 

 earthquake was of so superficial a character that "at Hot 

 Springs, while sev-ere shocks were felt on the surface, the 

 men in the mines, 200 feet deep, felt nothing cf them." 

 Now the evidence goes to show that the latter eaithquake 

 was directly connected with the eruption of a volcano in 

 the neighbourhood, so that, although the origin of the dis- 

 turbance may be underground, possibly at a very con- 

 siderable depth, the shocks are at a certain distance quite 

 superficial, and moreover are transmitted in ceitain defi- 

 nite directions. 



Taking all these facts together, they would rather seem 

 to favour the conclusions that at any rate a great many, 

 if not all, of the volcanic regions of the world are con- 

 nected, and that they are not merely parts of the earth's 

 surface which happen to be over isolated subterranean 

 furnaces, but places where access to the exterior is more 

 easy for the molten matter which lies underneath a great 

 part, perhaps all, of the earth's ciust. I must not be un- 

 derstood to be upholding the (shall I say exploded ?) 

 theory of the internal fluidity of the earth ; I merely 

 mean to point out that such coincidences in point of tin;e 

 ought to make one hesitate before rushing to the other 

 extreme, and looking upon volcanoes as mere local ec- 

 centricities. 



But it will be said, if there is any general commotion 

 under even the volcanic area of Europe, why do not the 

 e.xtinct volcanoes of Auvergne break out again.? Heie 

 is a difticulty which is not at all solved by the sugges- 

 tion that at first occurs to one, that as the raising of 

 the country has drained the enormous lakes, on the 

 borders of which these volcanoes stood, there is no 

 longer a supply of water to rou=e them into action, for 

 are there not lakes still in the Eifel, nay, are not those 

 lovely lakes actually in the craters of ex'inct volcanoes ? 



Again, who has seen the wonderful natural harbour of 

 Messina from the high ground above the town without 

 believing it to be an extmct submerged crater? If there 

 be still liquid rock below these craters, it maybe that they 

 are no longer the pomts of least resistance. And this is 

 the probable explanation of their inactivity ; for it must 

 not be imagined that an eruption of Etna or of Ve- 

 suvius, or of any other volcano, necessarily means an 

 ejection of ashes, lava, &c., from the crater, or from 

 any crater ; not at all, the weakest point in the vicinity 

 gives way, and thus we have the numerous cones formed 

 which surround every considerable volcano for some 

 distance. 



The mention of Auvergne leads me to make a few re- 

 marks on the disputed point, as to whether or not the 

 volcanoes in that country have been in eruption within 

 historic times, especially as I sec that a correspondent in 

 last week's Nature has come to the conclusion originally 

 drawn by '• an eminent historian and antiquary, Sir 

 Francis Palgrave," as long ago as 1S44, and adopted 

 by theological writers ever since, that because a bishop 

 of Vienne established Rogation days on account of 

 some alarming terrestrial phenomena which happened 

 in his diocese, therefore the volcanoes of Auvergne were 

 in action at the time. We have two documents which 

 refer to this matter, a letter written by Sidonius Apolli- 

 naris (who lived in the very centre of the Chaine des 



