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‘* Such beauty varying in the light 
Of living Nature cannot be portrayed 
By words, nor by the pencil’s silent skill, 
But is the property of him alone 
Who hath beheld it, noted it with care, 
And in his mind recorded it with love.” 
Located on our standpoint of Castle Head, a careful observer 
will speedily discover how different in outline some of the hills 
seen by him are from others. He will see one group of which the 
surface is comparatively even and unbroken, and another that is 
rough and rugged in the extreme. Looking towards Borrowdale, 
for instance, he will quickly perceive that the hills on the left of 
the lake, and those at the farther end are infinitely more wild and 
irregular than those on the right, which, in fact, have a somewhat 
tame and even outline. On the north too, he will see that the 
same comparatively smooth and unbroken appearance is presented 
by the forms of Skiddaw and Blencathra, notwithstanding their 
deeply furrowed sides. Now what is the cause of this difference 
of appearance? Why should one set of hills have a rough and 
hummocky exterior, and the other be regular and comparatively 
smooth? Like the form of the sea-coast line, it is explained by a 
knowledge of their geological structure. On examination we find 
that the more even-looking hills are formed out of a rock which is 
known as Skiddaw Slate—so called from the fact of its largely forming 
the mountain of Skiddaw. Itis a formation which consists mainly of 
beds of mudstone of nearly uniform hardness; so that it offers to 
the agents of denudation the same— or nearly the same—resistance 
at every part of it. Hence the regular outline of the hills in which 
it occurs. But the hills of rugged outline are built up of volcanic 
lavas and ashes, rocks of very different degrees of hardness, and 
therefore yielding variously to the denuding action of the elements. 
Whence their jagged and hummocky appearance. 
In, this way we might go on explaining nearly every feature 
of the rocks we see. Should we ask ourselves, for instance, why 
Castle Head, the hill on which we stand, rises so abruptly from the 
ground around it, the answer is at once apparent when we discover 
that the hill consists of a hard volcanic rock called Diabase, whilst 
