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lower one, and gradually vanish away to the north, as will be 
seen from the plan ; the northern part being only a rounded 
depression, with no flat tract at the bottom. But the most 
remarkable feature is the small depression at the northern 
end of the flat tract at the bottom of the upper valley, as 
will be seen from the plan. Sec. 1 is in the direction of the 
length of the valley, along the bottom, from the point marked 
d on the plan, to a short distance in the lower valley. The 
above-mentioned depression is shown at c of Sec. 1 ; the 
part from c to b is the bottom of the upper valley, and from 
b to a is the inclination down the centre of the round end 
of the lower, with the detritus at the bottom. The brook 
coming down the north-western arm of the valley has cut 
out a small ravine, and formed some small alluvial tracts in 
the detritus at the bottom of the valley, as will be seen from 
the plan and Sec. 4 ; and as we proceed downwards it has 
removed the whole, and brought the valley into a state in 
which there is no evidence of its not having been wholly 
excavated by the brook, as shown by Sec. 5, where the 
lowest dotted line shows the original level of the detritus. 
Taking all these facts into consideration, I think no one 
can imagine that any stream of water, such as now usually 
runs in such valleys, can have excavated Yedmandale ; and 
from it I think we may safely infer the same of other similar 
ones in the locality, which, owing to circumstances, do not 
retain their original structure, but have been modified by the 
action of the brooks running in them. It is, however, not 
so clear what other action produced them ; and though I do 
not wish to push theory farther than phenomena clearly lead, 
I must confess that a strong current from the north, when 
this part was below the level of the sea, offers a better ex- 
planation, in my opinion, than any other that I can suggest ; 
and I would remark that, when on the spot, this view of the 
subject presented itself to my mind most strongly. The 
