2iO 
TllE GEOLOGIST. 
hills, so to speak, is N.W. aud S.E., witH a narrow vale or channel 
Iviiig between, the striae will be found having the same undeviating 
direction right across from N.E. by N. to S.W. by S. This is 
exemplified in the hills bordering the vale of Newland, near Ulver- 
stone, where a brook now runs from 300 to 400 feet below the heights 
on each side. There is no question, however, but that the gill is 
deeper than when the ice crossed it, but the striation is repeated on 
the N.E. side down to 275 feet from the top, and at rather more than 
125 feet above the brook ; while it is a curious fact that this happens 
to be about the elevation above the brook, of the lowest obtained 
striae on the S.W. side. 
At the same time, although this is very likely to be the prevail- 
ing tendency of striae in Eurness, yet there are exceptions, and a 
slight deviation will sometimes occur between two points within a 
short distance of each other. Thus, on Grameswell Hill, deep 
groovings pass from N.N.E. to S.S.AY., while rather more than half 
a mile off the striation is from E.N.E. to AY.S.AY. Yet neither of 
the two striations can have any connection with the present features 
of the locality. The gill that passes under Gameswell on the west 
cuts directly N. and S., and the rocks with the latter striation are on 
the sout])-eastern slope of a fell, down which small drainage depres- 
sions pass to the E. and S.E. 
It should be conceded, I think, to the inexperienced student, that 
there may be great difficulty sometimes in selecting glacial striae out 
of "weathered " lines of cleavage and stratification in the slate rocks. 
The difficulty is not when they present their edges sharp, close, and 
regular; but when e.g. somewliat resembling the spreading leaves of 
an opened book, they have been furtlier worn into hoi'izontal hollows, 
ruts, or grooves ; and this, possibly, by the glacier passing over at 
right angles to them, rather than parallel with them, as would be at 
first suggested. The above is only one out of other instances of de- 
ception met with on decomposing slate rocks. It must occasionally 
happen that true striae may run ])arallel with either the cleavage or 
bedding ; but in these doubtful cases I have uniformly abandoned 
them, and it is not unlikely that good genuine striae, which the ex- 
perienced geologist would have noted down, may thus have escaped. 
On the craggy heights of the moors, as well as in some places ou 
the shore, the aspect of the rocks indicate that the principal denuding 
force has been carried over from the north. They generally present 
their smoothed sides to the north or north-east, their rugged ones to 
the opposite point ; deep ruts passing up the smooth incline answer- 
ing in point of depth to the opposition that incline had presented. 
In some instances the edges of the cleavage planes have been so 
shaved off", grooved across at right angles, and rounded, as strikingly 
to resemble the laminated structure of a shell-hill contour. 
"With regard to the form and outline of many of our hills, the 
beautiful description given at some length by Mr. Greikie, of the 
glaciation among the mountains of Scotland, might well serve for a 
