Phenomena in South America. 61 1 



With respect to these tables, it must be observed, that we can never feel sure 

 that the connexion of volcanic phenomena at very distant points is real, until 

 some strongly marked event takes place during the same moment at those 

 points, the intermediate country being likewise affected to a certain degree. 

 In the first two tables, the connexion of the West-Indian vents and the coast of 

 Venezuela may be admitted as almost certain *, nor is the distance very great, 

 being at most only 400 miles. But when, on the one hand, we include Quito, 

 distant from the above area more than 1200 miles, and, on the other, the Valley 

 of the Mississippi, the case is very much more doubtful. The coincidence 

 certainly is very remarkable, both in regard to the commencement and the 

 cessation of the long series of earthquakes which affected South Carolina, the 

 basin of the Mississippi, the Leeward Islands, and Venezuela : yet New Ma- 

 drid is more than 2000 miles from the latter. A repetition alone of such coin- 

 cidences can determine how far the increased activity of the subterranean 

 powers, at points so remote, is the effect of some general law, or of accident. 



We now come to the third table, with which we are more particularly con- 

 cerned. I have already described in detail the remarkable volcanic pheno- 

 mena which happened, in connexion with each other, on the morning of 

 February 20th, 1835, and likewise during the subsequent year. 



On January 20th, one month previously, three eruptions, as stated in the table, occurred almost at 

 the same hour in very distant points of the Cordillera. Near midnight on the 19th, the summit of 

 Osorno shone like a great star in the horizon ; and this appearance soon increased into a magnificent 

 glare of light, in the midst of which, by the aid of a telescope, great dark bodies were seen to shoot 

 upward and to fall down in endless succession. When I was at Valparaiso some time afterwards, 

 Mr. Byerbache, a resident merchant, informed me, that sailing out of the harbour one night very 

 late, he was awakened by the captain to see the volcano of Aconcagua in activity. As this is a 

 most rare event I recorded the date. Some time afterwards papers arrived from Central America 

 giving an account of one of the most fearful eruptions of modern times f. " On the 19th of Ja- 

 nuary, after twenty-six years' repose, a slight noise, attended with smoke, proceeded from the 

 mountain of Coseguina. On the following morning (the 20th) about half-past six o'clock, a cloud 

 of very unusual size and shape was observed by the inhabitants to rise in the direction of this 

 volcano." Enormous quantities of ashes and pumice were then ejected, and the air was darkened, 

 and the ground convulsed, during the three succeeding days. Nearly two months afterwards the 

 volcano was in action. Mr. Caldcleugh observes, that perhaps the only parallel case on record 

 is the well-known explosion of Sumbawa in 1815. 



When I compared the dates of these three events, I was astonished to 

 find that they agreed within less than six hours of each other. Aconcagua 

 is only 480 miles north of Osorno, but Coseguina is about 2700 north of 



* Humboldt's Personal Narrative, vol. ii. p. 226., and vol. iv. p. 26. 



t Caldcleugh on the volcanic eruption of Coseguina. Philosophical Transactions, 1836, p. 27. 

 VOL. V. SECOND SERIES. 4 R. 



