306 
EOCENE PERIOD. 
[Ch.XXII. 
bury, in Berkshire, is about five miles long and two in breadth. 
The upper and lower chalk, as will be seen in the accompany- 
ing section # , and the upper green-sand dip in opposite direc- 
tions from an anticlinal axis which passes through the middle 
of the valley along the line a, b, of the ground-plan (No. 78). 
*We subjoin an additional wood-cut, as conveying a scale of 
N. No. 80. S. 
Valley of Kingsclere. 
heights more nearly approaching to that of nature, althoug 
the altitudes, in proportion to the horizontal extent, are eve 
in this,, perhaps, somewhat in excess. On each side of the val 
ley we find escarpments of chalk, the strata of which dip in oppo 
site directions, in the northern escarpment to the north, an 
in the southern to the south. At the eastern and western ex 
tremities of the valley, the two escarpments become confluent 
precisely in the same manner as do those of the North an 
South Downs, at the eastern end of the Weald district, nea 
Petersfield. And as, a few miles east of the town last men- 
tioned (see Map, plate V.), the firestone, or upper green-sand 
is laid open in the sharp angle between the escarpment of th 
Alton Hills and the western termination of the South Downs f 
so in the valley of Kingsclere the same formation is seen t 
crop out from beneath the chalk. 
The reader might imagine, on regarding Dr. Buckland' 
section (No. 79) 3 where, for the sake of elucidating the geo- 
logical phenomena, the heights are greatly exaggerated in pro 
portion to the horizontal extent, that the solution of conti 
nuity of the strata bounding the valley of Kingsclere had been 
simply due to elevation and fracture, unassisted by aqueou 
causes; but by reference to the true scale (No. 80), it will 
* Copied by permission from Dr. Buckland's plate XVII., Geol. Trans., 2n 
Series, vol. ii. 
-j- See Mr. Murchison's map, plate XIV., ibid, 
