84 THE CLIMATE. 



low, but the frosts are by no means so severe as in Europe. I have never seen ice even in the 

 small streams, nor does snow lie any length of time on the ground. Greater cold is expe- 

 rienced in Chiloe than in Santiago or Concepcion ; but we must remember that it is nearer to 

 the pole and the rigorous climate of Cape Horn. 



" That which renders the winter, as well as some months of the other seasons, most disagree- 

 able, are the continual rains, with violent storms from the north, N.W., and west. It fre- 

 quently occurs that rain falls for an entire lunation without ceasing, accompanied by hurricanes 

 so furious that no one within the house is secure, and the largest trees are torn up by the roots. 



" Although the winter months, and a considerable part of the other seasons, are very dis- 

 agreeable, owing to the severity of the winds and exceeding quantity of rain, it cannot be 

 denied that the climate is healthy." Agiieros resided six years, on the island, and published 

 his volume in 1*791. 



In the narrative of the Voyages of the Adventure and Beagle, Vol. I, it is stated: "Capt. 

 Fitzroy arrived there in July, during the latter part of which, and the month of August, the 

 weather was very wet, with some heavy gales from the N.W.; but, in his meteorological journal 

 for those months, there is no record of the thermometer falling below 38, and it is recorded 

 to have fallen to that degree only on one occasion, the general height being from 45 to 50." 

 From the same volume the mean pressure of the barometer at 9 A. M. during twenty-two days of 

 July, 1829, was 29.927 inches, and the temperature of the air 46. 9. Five years later the 

 island was revisited by the same officer, from whose published journal I find that the mean 

 pressure at noon during fifteen days of June and July, 1834, was 29.723 inches (reduced to 

 32); the range of the barometer from 29.37 to 30.31 inches; the mean temperature at the 

 same hour 48. 6, and range from 40 to 53. At the time the barometer was so low it was 

 raining heavily, with a light air from the eastward ; when highest, the wind was from S.E., 

 light breezes, with cumulous clouds. Altogether, Chiloe is not so bad as it has been reputed, 

 and its ^temperature is nearly 20 higher than that of Boston harbor. 



It would be interesting to trace the climate of these several enumerated districts through each 

 of the seasons, but from some of them proper data are wanting ; and therefore, with brief 

 reference to the characteristics of spring and autumn at Santiago, most that remains to be said 

 will refer to the summer. If the winter at Coquimbo and Atacania is so dry and cloudless, 

 what must be their climates at mid-summer? 



The diurnal tide of the atmosphere always small at the capital not unfrequently has its 

 hours of maxima and minima reversed, in spring, by the amount of the extraordinary fluc- 

 tuations, and thus the means show greater pressure near 9 p. M. than near 9 A. M. If we 

 take a mean of the observations at the several hours as indicator of the oscillations, the 

 extreme vertical displacement, one day with another, amounts to .0085 of the whole atmo- 

 sphere, the limits of the barometer (reduced to 32) being from 28.069 to 28.104 inches. On 

 the other hand, the range of the temperature is very great, extending through more than 40 

 between the warmest and coldest hours of the days during the season, though the mean differ- 

 ence is only 20. 1, and the temperature of spring is 59. At the surface of the plain the ther- 

 mometer never fell so low as the freezing-point, although there were frequent deposits of snow 

 at small elevations above us on the Andes. Nor are the differences between the temperature of 

 the air and that of evaporation less remarkable : 15 was a common difference at the warmest 

 hours of the day; 24 was occasionally observed, and the mean was 6. 8. Yet rains were not 

 infrequent during the spring months, and September has uniformly been considered the most 

 cloudy month of the year. 



Three of the four thunder-storms we witnessed were in spring, two taking place within five 

 days of each other, in November, 1850, and the third in September, 1851. These are very rare 

 phenomena on the plain, and produce terror scarcely inferior to earthquakes. The first one 

 (November 25) was attended by very high barometer, unusual southerly wind, and heavy 

 cumulous clouds, and was followed by a copious fall of rain during eight hours. That of the 



