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Show 290 EOCENE PERIOD. ~ '0 ~ < ~ :l ;.. i: ~ ~ "'1:1"' ~ 1:: o:! ~ ~ ~ ..e ~ 0 ~ c,"' -5 l3 -5 t1 0 1i ..c ~ '0 ~ .::. ..::."' ~ "< ~ -a ·a !=l. ~ >. ..c d Q) i '0 :g I> .Q 1:- .~ g !>I) ~ d "< ·a t! r t<: ~., 00 :5 'S ~ ] ~ 1:: Q) ~ .; (Cb. XXI. Ch. XXI.] CHALK ESCARPMENTS ONCE SEA·CLIFFS. 291 val1ey excavated chiefly out of the argillaceous or marly bed, termed Gault (No. 2). The escarpment is continuous along the southern termination of the North Downs, and the reader may trace it from the sea at Folkstone, westward to Guildford and the neighbourhood of Petersfield, and from thence to the termination of the South Downs at Beachy Head. In this precipice or steep slope the strata are cut off abruptly, and it is evident that they must originally have extended farther. In the accompanying wood-cut (No. 65), part of the escarpment of the South Downs is faithfully represented, where the denudation at the base of the declivity has been somewhat more extensive than usual, in consequence of ~the upper and lower green-sand being formed of very incoherent materials, the former, indeed, being extremely thin and almost wanting. The geologist cannot fail to recognize in this view the exact likeness of a sea-cliff, and if he turns and looks in an opposite direction, or eastward, towards Beachy Head, he will see the same line of height prolonged. Even those who are not accustomed to speculate on the former changes which the surface has undergone, may fancy the broad and level plain to resemble the flat sands which were laid dry by the receding tide, and the different projecting masses of chalk to be the headlands of a coast which separated the different bays from each other. No.66. Chalk esca1'Pmcnt as seen from the !till above Steyning, Susse:c. The castle and village of Bramber in tile fo1·e-ground. Lowe1· terrace of firestone.-We have said that the upper 112 |