the Chonos
archipelago, where he had anchored two years before, and found that the
bottom of the sea had been raised more than eight feet. Some rocks
formerly covered at all times by the sea were now constantly exposed,
and an enormous quantity of shells and fish in a decaying state, which
had been thrown there by the waves, or suddenly laid dry during the
earthquake, attested the recent date of the occurrence. The whole coast
was strewed with uprooted trees.[624]

_Chili--Conception_, 1835.--Fortunately we have a still more detailed
account of the geographical changes produced in the same country on the
20th of February, 1835. An earthquake was then felt at all places
between Copiapo and Chiloe, from north to south, and from Mendoza to
Juan Fernandez, from east to west. "Vessels," says Mr. Caldcleugh,
"navigating the Pacific, within 100 miles of the coast, experienced the
shock with considerable force."[625] Conception, Talcahuano, Chillan,
and other towns were thrown down. From the account of Captain Fitz Roy,
R. N., who was then employed in surveying the coast, we learn that after
the shock the sea retired in the Bay of Conception, and the vessels
grounded, even those which had been lying in seven fathoms water: all
the shoals were visible, and soon afterwards a wave rushed in and then
retreated, and was followed by two other waves. The vertical height of
these waves does not appear to have been much greater than from sixteen
to twenty feet, although they rose to much greater heights when they
broke upon a sloping beach.

[Illustration: Fig. 69.]

According to Mr. Caldcleugh and Mr. Darwin, the whole volcanic chain of
the Chilian Andes, a range 150 miles in length, was in a state of
unusual activity, both during the shocks and for some time preceding and
after the convulsion, and lava was seen to flow from the crater of
Osorno. (See Map, fig. 69.) The island of Juan Fernandez, distant 365
geographical miles from Chili, was violently shaken at the same time,
and devastated by a great wave. A submarine volcano broke out there
near Bacalao Head, about a mile from the shore, in sixty-nine fathoms
water, and illumined the whole island during the night.[626]

"At Conception," says Captain Fitz Roy, "the earth opened and closed
rapidly in numerous places. The direction of the cracks was not uniform,
though generally from southeast to northwest. The earth was not quiet
for three days after the great shock, and more than