104 EARTHQUAKES. 



of the vessel was suddenly diminished from seven knots per hour to one knot : the sea was 

 greatly agitated, apparently lifting her up twenty feet/ and the master thought her dragging 

 over a sand-bank. At Juan Fernandez the sea rose without warning to the level of the little 

 bay on the N.E. side, and, during its rapid recession a few minutes later, a tremendous noise 

 was heard, and a column of white smoke burst from it about a mile from Bacalao Point. At 

 the same instant, the shock was felt. Two hundred yards of the bay was left bare by the reflux ; 

 and with the second rush, the water reached 15 feet above its usual level, carrying every thing 

 before it. All through the night, bursts of flame illuminating the whole island rose from the 

 spot where the smoke had been seen to issue ; but when it was sounded a month later, 69 

 fathoms of water covered it. 



Considering the great violence of this earthquake and the extent of territory disturbed, the 

 loss of life was comparatively small, in all not exceeding 200 persons. It is also worthy of 

 remark, that while all the buildings on alluvial soil within a certain distance of Concepcion were 

 destroyed, three houses on rock foundation in Talcahuano, and the villages of Grualqui and Here 

 within that distance, but on the granite of the Coast Cordilleras, remained uninjured.* Nor 

 did Antuco, at the very foot of the volcano of that name, suffer harm. 







1837. 



The governor of Valdivia, in an official report to the Intendente, dated 7th November of this 

 year, says that the earthquake of that morning, beyond all question, was the most severe ever 

 known. It began at five minutes past 8 o'clock, and for ten minutes the motion of the earth was 

 so violent that one could only stand with great difficulty. From that time until 9^, strong shocks 

 occurred every few moments ; and tremors, gradually diminishing in force, continued throughout 

 the day. Both churches and all the public offices were thrown down ; and if the other build- 

 ings did not share the same fate, it was because they are constructed of wood and yielded to 

 flexure more readily. f 



This was the last great earthquake prior to our arrival in the country. Tremors in one 

 province or another were of daily occurrence, and are duly chronicled in the local papers of the 

 period ; but they had no general interest, and no facts are recorded with them likely to benefit 

 the geologist. Nor do I propose to specify in this place the multitude observed in the ensuing 

 three years, but only such as exhibited peculiarities, or merit notice by the extent of the dis- 

 turbed district. In Appendix A will be found all, of which records were made both by Senor 

 Troncosa at La Serena, and ourselves at Santiago. 



1849. 



At La Serena, the month of November, 1849, was particularly marked. There were tremors 

 on the 8th, 12th, 13th, 14th, 16th ; five on the 18th, six on the 19th, four on the 20th, one 

 on the 21st, one on the 23d, five between the 24th and 26th, one on the 27th, two on the 28th, 

 and one on the 30th : in all, thirty-one shocks during less than the same number of days. 

 That which took place at 6A. 12m. A. M. (M. T. Santiago) on the 18th, was by far the most 

 violent, and the earth was in motion for 84 seconds. The line of oscillation, indicated by the 

 swinging of a barometer suspended at two inches from the wall, was from N.W. to S.E. The 

 barometer would have been broken had it not been held, though no injury was done to houses. 

 At the port, a sea- wave 16 feet higher than tide-level followed immediately after the shock, 

 greatly injuring the copper-smelting furnaces and other property on the beach. A short, ter- 

 rifying noise preceded it. The same shock was felt sensibly at Santiago and Valparaiso, 

 rousing the inmates of a hotel in the former city where we were staying, and starting them, as 



* Similar consequences were observed during the great Catania and Jamaica earthquakes in 1693 and 1694. Phil Trans., 

 Vols. XVII and XVIII. 

 t Araucano. December 8, 1837 



