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have, however, in the case of Yedmandale, an association of 
circumstances that have, in a remarkable manner, preserved 
phenomena which clearly prove that they are not due to this 
agency, but to some other not now in action in the locality. 
The configuration of that branch of this valley which 
exhibits these facts will be seen from the accompanying plan. 
The sides in every part, except those which I shall mention 
below, are inclined at an angle of 30°, and are quite straight 
from the top to the bottom, as shown by the sections. In 
the bottom we have a deposit of loose, coarse, not much 
water-worn detritus, of local origin, which is not deposited 
horizontally, but undulated, as indicated by the shading. It 
is owing to the coarse nature of this deposit, and to the fact 
of the neighbouring valley of the Derwent being about 300 
feet deep, whilst Yedmandale is about 100 feet, that there 
never has been a brook in its northern arm ; for the chief 
drainage passes into that deeper-cut valley, and what little 
runs into Yedmandale sokes away amongst the coarse de- 
tritus, without forming any brook. We have, however, a 
stream in the north-western portion of the valley, as will be 
seen from the plan ; which, however, after passing along for 
some distance, is lost amongst the detritus, in a part below 
that shown in the plan. Sec. 3 is across the northern arm 
of the valley, in the part indicated on the plan, the steep 
sides and the deposit at the bottom being shown ; the dotted 
line in this and the other sections indicating the position of 
the surface before the excavating took place. Passing north- 
wards from this part, it will be seen that the end of the valley 
is round and amphitheatre-like ; the central portion being 
inclined at an angle of 14°, and each way quickly becoming 
steeper. Ascending up the centre we come to a small valley 
with a flat bottom, as shown by Sec. 2 ; and though I could 
not ascertain it for certain, I think it contains no detritus. 
The steep sides of this upper valley round into those of the 
