22 
MR. CALDCLEUGH ON THE GREAT EARTHQUAKE IN CHILE. 
entitled to some degree of credit, that on the morning of the convulsion all the dogs 
disappeared from Talcahuano. 
The summer in Chile had been rather colder than in preceding years. The mean 
of the thermometer in Santiago (two thousand feet above the level of the sea) for the 
months of January and February was 72° of Fahr. The mean of the barometer for 
the same period was 28 - 25, which is about one tenth of an inch below its usual 
height. 
From the 1st of February the barometer was unusually low in Santiago; and on 
the 14th, six days prior to the earthquake, the barometer at half past 6 a.m. stood 
at 28T, the thermometer at the same time being 73°. A slight oscillation, which 
lasted twenty seconds, was felt on this day ; on the 20th the barometer marked 28T7, 
and the thermometer rose to 76° : the weather fine. In Concepcion, in the night ot 
the 1 7 til to 18th the barometer fell four tenths of an inch, but gradually recovered 
itself, and indicated nothing extraordinary on the morning of the 20th. In Valdivia, 
according to the observations most obligingly communicated to me by Capt. FitzRoy, 
of the Beagle Surveying Ship, the barometer stood on the 16th of February at 29'92, 
and continued to rise gradually until the end of the month, with an increased tem- 
perature. From my own observations, deduced from many oscillations, I have re- 
marked that the barometer usually falls shortly before any considerable shock, and 
then returns to its ordinary mean. On the 26th of September 1829, a very severe 
earthquake was experienced in this city, which did much damage to most buildings; 
the front of the house I then inhabited fell down ; and it is worthy of remark, that 
the instant after every shock a burst of rain fell, which soon moderated, until a fresh 
tremor caused it to recommence. 
The igneous vents of the whole range of the Cordillera may be said to have been 
in remarkable activity both preceding and at the moment of the late convulsion. From 
the flat-topped volcano of Yanteles, in front of Chiloe, to the lofty range of the Andes 
in Central America, all the information which has been obtained gives details of 
violent eruptions. On the 20th of January the volcano of Osorno, north-east of 
Chiloe, burst forth with inconceivable fury; and the lava was seen at night rushing 
out of the crater and rolling down the side of the mountain, elevated 3900 feet above 
the level of the sea. The reflection of the flame reached double that height, and is 
described to me by Mr. P. G. King, of the Beagle, as presenting the most magnificent 
object he had ever beheld. From the plains of Talca, eighty leagues to the south of 
the capital, two volcanos were observed in activity a few days after the 20th of 
February. They are both situate near the lake of Mondaca, twenty-five leagues 
eastward in the Cordillera: and another new rent was observed on the estate called 
Cerro Colorado, on the right bank of the river Maule, and near its source. The 
volcano of Petoroa, and another near it whence a stream of asphaltum flows, and 
those of Maypu and Aconchagua have also been for some months in a state of activity. 
In the month of January the volcano of Coseguina in Central America became 
