318 EOCENE PERIOD. [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 V 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. 



