11 
CHAP. II. 
GEOLOGICAL STRUCTURE OF SUSSEX. 
The investigation of the geology of this district is 
attended with considerable difhcidty. The dis- 
})lacement and disintegration wliicli many of the 
strata liave sustained ; the excess of soil and vege- 
tation witli wliich, in most jilaces, their basseting 
edges are covered at the line of junction ; and the 
absence of sections in those situations where the 
relative position of the rocks is involved in ob- 
scurity, present numerous, and in some instiuices 
insuperable, obstacles to accurate examination. 
Under such circumstances, induction and analogy 
must supply the place of actual observation ; but, 
the relative position of the principal masses having 
been correctly ascertained, whatever errors may 
have originated from the causes alluded to are of 
minor importance ; since they chiefly relate to the 
geographical extent of the strata, and cannot affect 
the geological deductions that may be di'awTi from 
these researches. 
For the information of the general reader, it 
may be necessary to observe, that in Sussex, as in 
every other jiart of England, the strata maintain a 
certain order of superposition ; and that, however 
great the disjilaceinent or interruption they may 
have sustained, this order is never inverted. To 
