EARTHQUAKES. 212- 



feel as if we trod upon the very focus of destruction. This 

 condition of the mind is not of long duration, although it 

 takes its origin in the deepest recesses of our nature ; and 

 when a scries of faint shocks succeed one another, the inha- 

 bitants of the country soon lose every trace of fear. On the 

 coasts of Peru, where rain and hail are unknown, no less than 

 the rolling thunder and the flashing lightning, these luminous 

 explosions of the atmosphere are replaced by the subterranean 

 noises which accompany earthquakes.* Long habit, and the 

 very prevalent opinion that dangerous shocks are only to be 

 apprehended two or three times in the course of a century, 

 cause faint oscillations of the soil to be regarded in Lima with 

 scarcely more attention than a hail storm in the temperate 

 zone. 



Having thus taken a general view of the activity, the inner 

 life as it were, of the Earth, in respect to its internal heat, its 

 electro-magnetic tension, its emanations of light at the poles, 

 and its irregularly-recurring phenomena of motion, we wit 

 now proceed to the consideration of the material products, the 

 chemical changes in the earth's surface, and the composition 

 of the atmosphere, which are all dependent on planetary vital 

 activity. We see issue from the ground steam and gaseous 

 carbonic acid, almost always free from the admixture of 

 nitrogen,! carburetted hydrogen gas, which has been used in 



* [" Along the whole coast of Peru the atmosphere is almost uni- 

 formly in a state of repose. It is not illuminated by the lightning's 

 flash, or disturbed by the roar of the thunder; no deluges of rain, no fierce 

 hurricanes, destroy "the fruits of the fields, and with them the hopes of 

 the husbandman. But the mildness of the elements above ground is 

 frighfully counterbalanced by their subterranean fury. Lima is fre- 

 quently visited by earthquakes, and several times the city has been 

 reduced to a mass of ruins. At an average, forty-five shocks may be 

 counted on in the year. Most of them occur in the latter part of 

 October, in November, December, January, May, and June. Experience 

 gives reason to expect the visitation of two desolating earthquakes in a 

 century. The period between the two is from forty to sixty years. The 

 most considerable catastrophes experienced in Lima since Europeans 

 have visited the west coast of South America happened in the years 

 1580, 1630, 1687, 1713, 1746, 1806. There is reason to fear that in the 

 course of a few years this city may be the prey of another such visita- 

 tion." Tschudi, op. cit.] Tr. 



t Biadiofs comprehensive work, Wilrmelehre des inneren Erdkfo* 

 pers. 



