318 
EOCENE PERIOD. 
f Ch. XXII. 
alluviums which cover the surface of Scotland, a country which 
probably became land long before the commencement of the 
tertiary epochs. 
Elevation of land gradual. — As we have assumed, through- 
out this and the preceding chapter, that the elevatory force 
was developed in a succession of minor convulsions in the south- 
east of England, we may seem called upon to answer an ob- 
jection which has been drawn from the verticality of the strata 
in the Isles of Wight and Purbeck. Mr. Conybeare has 
remarked, that the vertical strata are traced through a district 
nearly 60 miles in length, so that ' if their present position were 
the effect of a single convulsion, no disturbance in the least 
comparable with it has occurred in modern times As we 
can by no means dissent from this proposition, we only ask 
where is the evidence that a single effort of the subterranean 
force, rather than reiterated movements, produced that sharp 
flexure of which we suppose the vertical strata of the Isle of 
Wight to form a part, the remainder of the arc having been 
carried away by denudation. 
It appears extremely probable that the Cutch earthquake of 
1819, so often alluded to by usf, may have produced an in- 
cipient curve, running in a linear direction through a tract at 
least 60 miles in length. The strata were upraised in the 
Ullah Bund, and depressed below the level of the sea in the 
adjoining tract, where the fort of Sindree was submerged. It 
would be impossible, if the next earthquake should raise the 
Bund still higher, and sink to a lower depth the adjoining 
tract, to discriminate, by any geological investigations., the dif- 
ferent effects of the two earthquakes, unless a minute survey 
of the effects of the first shock had been made and put on 
record. In this manner we may suppose the strata to be bent, 
again and again, in the course of future ages, until parts of 
them become perpendicular. 
To some it may appear, that there is a unity of effect in the 
* Phil. Mag. and Annals, No. 49, new Series, p. 21. 
f Vol, i., Second Edition, p. 465, and vol. ii., First Edition, p. 265, 
