of the Ground near Folkftone. 225 
As I intend, in explaining the caufe of the finking of the 
ground AA to you, to advance an opinion of my own, and to 
controvert what the reverend Mr, Sac&ette formerly faid 
upon the fubjedt, it may be neceflary to explain the nature of 
the foil, as far as it is open to view, in the neighbourhood of 
Folkftone. 
The chalk cliffs FF, which begin at Dover, form oppofite 
Folkftone town high hills, and leaving the fhore, there is a 
a large track of arable and pafture land between them and the 
Fea. 
Part of this ground is fhewn in the view at G, and is a kind 
of marie, which contains pyrites, fragments of the Corna 
Ammonis, and many other foflil bodies. 
Next to the marie is a loofe fandy foil (fee the cliff DD) 
intermixed with a very large, hard, and coarfe kind of ftone, 
in which are often found foflil oyfter fliells. 
This fandy foil refts upon a marie, which at the cliff DD 
is in fome places three or four feet above the beach, and when 
wet is very flippery. A ftratum of this marie extends for 
many miles on the coaft, and where it is not fufficiently co- 
vered with land to bear any weight, it is in many places a 
quag, and dangerous to pafs over. 
Through this track of land I have delcrihed, there are many 
drains of water, which may be fupplied partly from the falling 
of the rains in wet feafons, and partly from the fprings hiding 
from the hills ; and there is reafon to fuppofe, that in a loofe 
foil thefe drains form channels in a courfe of time. At the 
place where the ground has funk before, and is now finking, 
there is a drain from the marie under the fand ; and I am of 
opinion, that the courfe of the water is in the fame direction 
Vol. LXXVI. G g as 
