1835.] AND ERUPTIVE FORCES. 311 
a long tine in eruption, and ten months afterwards were again 
influenced by an earthquake at Concepcion. Some men, cutting 
wood near the base of one of these volcanos, did not perceive the 
shock of the 20th, although the whole surrounding Province was 
then trembling ; here we have an eruption relieving and taking 
the place of an earthquake, as would have happened at Con- 
cepcion, according to the belief of the lower orders, if the 
voleano of Antuco had not been closed by witchcraft. Two 
years and three quarters afterwards, Valdivia and Chiloe were 
again shaken, more violently than on the 20th, and an island in 
the Chonos Archipelago was permanently elevated more than 
eight feet. It will give a better idea of the scale of these phe- 
nomena, if (as in the case of the glaciers) we suppose them to 
have taken place at corresponding distances in Europe :—then 
would the land from the North Sea to the Mediterranean have 
been violently shaken, and at the same instant of time a large 
tract of the eastern coast of England would have been perma- 
nently elevated, together with some outlying islands,—a train of 
volcanos on the coast of Holland would have burst forth in 
action, and an eruption taken place at the bottom of the sea, near 
the northern extremity of Ireland—and lastly, the ancient vents 
of Auvergne, Cantal, and Mont d’Or would each have sent up 
to the sky a dark column of smoke, and have long remained in 
fierce action. Two years and three quarters afterwards, France, 
from its centre to the English Channel, would have been again 
desolated by an earthquake, and an island permanently upraised 
in the Mediterranean. 
The space, from under which volcanic matter on the 20th was 
actually erupted, is 720 miles in one line, and 400 miles in another 
line at right angles to the first: hence, in all probability, a sub- 
terranean lake of lava is here stretched out, of nearly double the 
area of the Black Sea. From the intimate and complicated man- 
ner in which the elevatory and eruptive forces were shown to be 
connected during this train of. phenomena, we may confidently 
come to the conclusion, that the forces which slowly and by little 
starts uplift continents, and those which at successive periods 
pour forth volcanic matter from open orifices, are identical. 
From many reasons, I believe that the frequent quakings of the 
earth on this line of coast are caused by the rending of the strata, 
