100 EARTHQUAKES. 



1835. 



So many accounts* of the great earthquake which took place on the 20th February, 1835, 

 have already been published, that repetition of all the details here would be supererogation. 



It is reported, that the mercurial column of a barometer fell four or five tenths of an inch 

 between the 17th and 18th, though it rose to its normal height before the 20th ; but as such a 

 depression here is invariably attended by a gale and much rain, and it is known that the weather 

 had been fair, great doubt hangs over the observations. When flocks of sea-birds were seen 

 flying towards the interior an hour or two before the shock, although it was a cloudless summer 

 morning, the weather-wise regarded it as ominous of an approaching storm. At forty minutes 

 past 11 o'clock the tremor commenced without noise, its violence gradually increasing during 

 the first half minute, yet not so much as to cause general alarm. Meanwhile the rumble was 

 heard, and at the end of that time the convulsive motion became so strong that the whole 

 population fled to open places for safety. Before a minute had elapsed, the awful motion so 

 increased that people could scarcely stand; and in thirty seconds more, an overpowering shock 

 caused universal destruction. Concepcion was a fourth time in ruins its people shrieking 

 under the agony of terror and bodily injury ; the very ground on which they were prostrated 

 gaping wide with every throb, and the atmosphere almost irrespirable with dust. From the 

 first tremor to the termination of the great shock was two and a half minutes, during the longer 

 portion of which time none were able to stand unsupported, even animals spreading out their 

 legs to avoid overthrow, and birds taking to the wing. Nor were these brute creatures less 

 terrified than man, as they evinced by excessive trembling and moans or wild screams. 



It was the general opinion that the undulations had come from the southwest. All the walls 

 thrown down had, without exception, fallen to the N.E.; those which presented their ends to the 

 point whence the waves came, if not broken and scattered, were fearfully fractured. The 

 fissures in the ground generally, though not uniformly, extended in a S.E. and N.W. direction, 

 corresponding with the lines of undulation or principal flexure. When most excessive, besides 

 the waving or undulatory, there were also felt vertical, horizontal, and circular motions. The 

 cathedral walls exhibited each of these kinds of motion. They were of good brick and mortar, 

 four feet thick, and supported by stout buttresses. That fronting the N.E. was thrown to the 

 ground, part of the angular blocks into which its masonry was broken having been rolled to a 

 distance in the plaza; the side-walls, standing N.E. andS.W., remained erect though broken ; 



of 1322. The only event noted was a fall of the barometer greater than had ever been known before or since. There was rain 

 three days afterward. 1 attribute the fall of the barometer to the actual loss of mercury which was thrown out of its cistern 

 during the shock, but Don Domingo Reyes assures me it was a true depression. At Valparaiso the sea fell remarkably. 



" 2d. What the traveller whom you cite asserts respecting the smoke that he saw thrown out on the Dehesa and Maypu mount- 

 ains, at the time of the earthquake of 1829, is wholly untrue. 



" 3d. I have not yet been able to learn anything of the condition of the volcanoes to the north of Talca. 



"4th. The volcano of Maypu, also called San Jose, is in activity; and, especially during summer evenings, maybe seen 

 ejecting smoke. This is attested by Don Juan de Dios Correa, who perceives it from his hacienda, the Compania; by Don 

 Domingo Reyes, and various other persons whom I have asked." 



With great deference for the opinion of these gentlemen, it may be suggested that the smoke supposed to be seen is only 

 cloud formed by rapidly rising warm air from the valley just after the influence of the sun on the mountain tops ceases, and the 

 light is probably that of summer lightning. It will be seen further on that similar phenomena over the same peak were pointed 

 out to me after the earthquake of December 6, 1850, but which were unquestionably of the nature just indicated. 



* See the admirably graphic narratives of Capt. Fitzroy and Mr. Chas. Darwin: Surveying Voyages of the Adventure and 

 Beagle, Vols. II and III ; 

 Journal Royal Geographical Society, Vol. VI; 

 Transactions Geological Society, London, Vol. V, second series ; 

 Alison: Geological Transactions, 1835; 

 Caldcleugh: Philosophical Transactions, 1836; 

 M. Coste: Comptes Rendus, 1838; 

 Padre Guzman : El Chileno Instruido en su Pais, Vol. II; 

 Sutcliffe: Account of the Earthquake that occurred on the Island of Juan Fernandez and Talcahuano: London, 1839 



