In my opinion,
we have scarcely beheld, since leaving England, any sight so deeply
interesting.
In almost every severe earthquake, the neighbouring waters of the
sea are said to have been greatly agitated. The disturbance seems
generally, as in the case of Concepcion, to have been of two kinds:
first, at the instant of the shock, the water swells high up on the
beach with a gentle motion, and then as quietly retreats; secondly,
some time afterwards, the whole body of the sea retires from the
coast, and then returns in waves of overwhelming force. The first
movement seems to be an immediate consequence of the earthquake
affecting differently a fluid and a solid, so that their respective
levels are slightly deranged: but the second case is a far more
important phenomenon. During most earthquakes, and especially
during those on the west coast of America, it is certain that the
first great movement of the waters has been a retirement. Some
authors have attempted to explain this, by supposing that the water
retains its level, whilst the land oscillates upwards; but surely
the water close to the land, even on a rather steep coast, would
partake of the motion of the bottom: moreover, as urged by Mr.
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