914 PROFESSOR J. PRESTWICK OR THE EVIDENCES OF A SUBMERGENCE 
to the extension of the land flood-waters, over what was then part of the continental 
area ; for, unless the Loess were older than the raised beaches, it is obvious, as those 
beaches extended all round the islands, that at the time of the deposition of the 
Loess, the islands were then, as now, detached from the mainland. The Loess in fact 
is closely connected with the “ head ” and not infrequently associated with it. A 
thin layer of an angular rubble similar to that which forms the “ head,” is also often to 
be found at the base of the Loess, and as the rubble is newer than the beaches, so must 
the Loess likewise be newer, and subsequent therefore to the severance of the islands 
from the mainland. Further, if the formation of this brick-earth cannot be 
attributed to floods or to a rain-wash from higher ground, it must have an origin 
independent of those to which the Loess is ordinarily assigned. 
Fig. 6 .—Section on the hill near St. Andreevs. 
a. Light brown Loess with a few angular rock fragments (a') at base, 4 to 6 feet. 
It. Decomposed granite, 4 to 8 feet. The solid rock does not show here. 
On the other hand—that a uniform sediment of that character should be formed 
during such a submergence as we have described, is, owing to the waste of the softer 
surface beds and decomposed rocks by the advancing waters, what we might expect. 
This w^aste was general over all the area submerged, and the waters must have been 
rendered turbid to a considerable distance from the coast,* so that not only the main¬ 
land but the adjacent islands also were covered with a mantle of sedimentary matter 
deposited during those periods of comparative quiet or lulls, which are shown to have 
occurred in the formation of the Head. The absence of marine remains is readily 
accounted for by the temporary nature of the occupation of the land by the sea 
waters, as well as by the circumstance that the waters would be rendered for a time 
unfit for the habitation of marine life. We shall revert to this subiect ao-ain when 
we have to speak of the continental Loess. 
If we suppose that the Loess in these islands was deposited during and after 
submergence, it follow's that as the land rose, it would be removed where it was 
in the way of the effluent currents, and carried with the angular rubble down to lower 
levels, or to a distance. That this was the case is shown by the fact that the “ head,” 
which covers the beaches, consists of angular local rubble, with Loess or brick-earth 
(derived from the plateaux) as a matrix and forming occasional seams and overlying 
beds. The following diagram (fig. 7) will illustrate my meaning. 
* On the coast of China the sea is coloured yellow to a distance of 100 miles from land by the fine 
Loess-mud carried down by the luvers. 
