396 
LAMPLUGH : GLACIAL SECTIONS. 
jammed at every sharp curve, and thus exerting great pressure on 
the frozen slopes of the high land adjoining. Under this view, the 
fresh-water remains and the patches of older gravel and silt 
would be readily explained as relics of a time of comparative 
quiescence ; and the fresh-water marls may represent a continu- 
ance of the series under changed conditions, the flowing water 
having been diverted or withdrawn, and having given place to 
stagnant ponds and marshes. 
I must confess, however, that this — like so many theories — 
looks more plausible when written out, (more plausible, in fact, 
than I meant it to be) than when applied by one standing before 
the actual section ; many unexplained points or opposing facts 
remaining now in the background which then stood out promin- 
ently. Still it remains the most likely solution that has suggested 
itself to me and probably contains some truth. 
Two years ago, I recorded* the occurrence of freshwater 
remains in the boulder-clay on the beach between sections 1 and 
2, at that time stating my inability to refer them to their place in 
the series. These remains consisted of fine clayey mud and sandy 
silt with shells of one species, Limncea peregra, and patches of 
peat and gravel — the whole greatly disturbed and crushed. These 
I can now refer with certainty to the base of the gravel No. 2, 
they having evidently been forced into the boulder- clay in the 
same way as has the gravel throughout the section. The patches of 
unstained gravel with silt and peat shown at the base of the en- 
larged Section 2,t I look upon as fragments of the same bed, and 
there are more traces of it above the boulder clay in that part of 
of section 2 south of F. 
I have mentioned that what seem to be lines of bedding 
appear in the Purple Clay near the termination of the middle gravel 
* Geol. Mag., Sept., 1879, p. 393. 
+ The streaks of marly clay with shells, xx of this section are marked 
' doubtful,' as the upper part of the section has been disturbed in making 
the road and the defences, and I thought it possible these might then have 
been introduced from the marls above, though they seem to be in place. 
