CHALK FORMATION. 
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into Cambridgeshire, by Dunstable, Hitching, 
Baldock, and Royston, to Gogmagog Hills, near 
Cambridge. The second, passing from Berkshire 
eastward, stretches through Surrey, where it forms 
the Hog’s Back, that beautiful ridge which extends 
from Farnham to Guildford, and then appears at 
Boxhill. This branch forms the hilly country and 
the downs north of Reigate, Bletchingley, and 
Godstone. It enters Kent to the north of Wes- 
terham, and extends by Riverhead to Wrotham, 
south of Hartford, Rochester, Lenham, and Can- 
terbury, to Folkstone and Dov^er. One division 
of tliis ridge is continued to the north coast of 
Kent, by Feversham, near Sheppey, Margate, and 
the North Foreland to Ramsgate. 
“ The third range, leaving Wiltshire and Berk- 
shire, enters Hants, and to the south passes round 
Petersfield, then, stretching to the east, forms a 
barrier against the sea along the coast from Chi- 
chester, constituting the South Downs ; and ranges 
from Maple-Durham, Houghton, Steyning, and 
Lewes, as far as Beachy Head.” * 
Insular parts occur in the Isle of Thanet and 
Isle of Wight, t 
In France, the chalk prevails on the skirt of the 
western boundary of Mount Jura, extending nearly 
in a direction from S.E. to N. W., and covering a 
space of at least 210 miles long and .00 broad. 
* Townsend’s Moses, vol. i. page 142. 
f Smith’s Strata. For a more j)articiilar account of the range and 
extent of the chalk formation, vide Phillips’s Geological Outlines, edition 
of 1822, p. 77. 
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