nd Ischia.[727]

_Permanence of the ocean's level._--In concluding this subject I may
observe, that the interminable controversies to which the phenomena of
the Bay of Baiae gave rise, have sprung from an extreme reluctance to
admit that the land, rather than the sea, is subject alternately to rise
and fall. Had it been assumed that the level of the ocean was
invariable, on the ground that no fluctuations have as yet been clearly
established, and that, on the other hand, the continents are inconstant
in their level, as has been demonstrated by the most unequivocal proofs
again and again, from the time of Strabo to our own times, the
appearances of the temple at Puzzuoli could never have been regarded as
enigmatical. Even if contemporary accounts had not distinctly attested
the upraising of the coast, this explanation should have been proposed
in the first instance as the most natural, instead of being now adopted
unwillingly when all others have failed.

To the strong prejudices still existing in regard to the mobility of the
land, we may attribute the rarity of such discoveries as have been
recently brought to light in the Bay of Baiae and the Bay of Conception.
A false theory, it is well known, may render us blind to facts which are
opposed to our prepossessions, or may conceal from us their true import
when we behold them. But it is time that the geologist should, in some
degree, overcome those first and natural impressions, which induced the
poets of old to select the rock as the emblem of firmness--the sea as
the image of inconstancy. Our modern poet, in a more philosophical
spirit, saw in the sea "The image of eternity," and has finely
contrasted the fleeting existence of the successive empires which have
flourished and fallen on the borders of the ocean with its own unchanged
stability.

------Their decay
Has dried up realms to deserts:--not so thou,
Unchangeable, save to thy wild wave's play:
Time writes no wrinkle on thine azure brow;
Such as creation's dawn beheld, thou rollest now.

CHILDE HAROLD, Canto iv.

CHAPTER XXX.

ELEVATION AND SUBSIDENCE OF LAND WITHOUT EARTHQUAKES.

Changes in the relative level of land and sea in regions not
volcanic--Opinion of Celsius that the waters of the Baltic Sea and
Northern Ocean were sinking--Objections raised to his
opinion--Proofs of the stability of the sea level in the
Baltic--Playfair's hy