76 
F. W. Oliver. 
The bank may run straight, but more usually it is gently curved— 
the convex face being presented to the sea. 
As a rule this type runs at some distance from the shore-line, 
the protected area between bank and shore being occupied by salt 
marshes subject to the tides. 
In effect these salt-marshes form a littoral shelf, of varying- 
width, along the outer edge of which the shingle rests (Text-fig. 2). 
H 
* • *• mum . * % , * * ' _• • » ♦ .. • - 
Fig. 2. Diagrammatic sections of Blakeney Bank (B) and Chesil Bank 
(C)”to show the relation of the shingle to the littoral shelf (L.S.) and mainland 
(M) Ch, channel ; F, water level of Fleet; H and L, high and low tide- 
marks. The shingle is drawn black. The vertical scale is much exaggerated. 
As a consequence of their sheltered position such marshes 
offer facilities for reclamation by the construction of earthen mounds 
or banks at right angles to the shore, and high enough to exclude 
the tides. In cases in which advantage has been taken of these 
facilities the shingle spit acquires some economic importance, for 
much depends upon its stability as the bulwark of the reclaimed area. 
Hook-Formation. 
The majority of shingle spits in England pursue their course 
from the point of attachment for several miles without any special 
topographical episode or change of type—apart from a slight 
widening here and a narrowing there (Text-fig. 4, p. 79). Sometimes 
this condition persists to the apex, especially in the case of banks 
still in active growth like the Aldeburgh bank in Suffolk. More 
usually, however, the apex shows a marked landward deflection, in 
the form of a hook, and frequently several hooks are present in 
close proximity (Hurst Castle, Hamstead Dover, Text-fig. 4), whilst 
occasionally extremely complex hook-systems occur, as at Blakeney 
(Text-fig. 3). 
