Ch. IX.] 
PROOFS OF SUCCESSIVE ELEVATION. 
113 
destroyed, and every trace of the successive rise of the land will 
be obliterated. 
We have been led into these observations, in order to show- 
that the principal features in the physical geography of Sicily 
are by no means inconsistent with the hypothesis of the succes- 
sive elevation of the country by the intermittent action of 
ordinary earthquakes *;. On the other hand, we consider the 
magnitude of the valleys, and their correspondence in form with 
those of other parts of the globe, to lend countenance to the 
theory of the slow and gradual rise of subaqueous strata. 
We have remarked in the first volume f , that the excavation 
of valleys must always proceed with the greatest rapidity when 
the levels of a country are undergoing alteration from time to 
time by earthquakes, and that it is principally when a country 
is rising or sinking by successive movements, that the power of 
aqueous causes, such as tides, currents, rivers, and land-floods, 
is exerted with the fullest energy. 
In order to explain the present appearance of the surface, 
we must first go back to the time when the Sicilian forma- 
tions were mere shoals at the bottom of the sea, in which the 
currents may have scooped out channels here and there. We 
must next suppose these shoals to have become small islands of 
which the cliffs were thrown down from time to time, as were 
those of Gian Greco, in Calabria, during the earthquake of 
1783. The waves and currents would then continue their 
denuding action during the emergence of these islands, until 
at length, when the intervening channels were laid dry, and 
rivers began to flow, the deepening and widening of the vai- 
* Since writing the above I have read the excellent memoir of M. Boblaye, on 
the alterations produced by the sea on calcareous rocks on the sbores of Greece. 
By examining the line of littoral caverns worn by the waves in cliffs composed of 
the harder limestones, together with the modes of decomposition of the rock, acted 
upon by the spray and sea air, as well as lithodomous perforations, and other 
markings, he has proved that there are four or five distinct ranges of ancient sea 
cliffs, one above the other, at various elevations in the Morea, which attest as 
many successive elevations of the country. Journal de Geologie, No. 10. Feb. 
1831. 
t Chap. xxiv. 
Vol. III. I 
