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number of quarries have been opened, and extensive excavations 
made, especially at Loughrigg, Elterwater, Hallgarth, Moss Rigg, 
Hodge Close, Tilberthwaite, and Saddle Stone; the last named 
is at a high elevation on Coniston Old Man. In some of the 
quarries, notably those worked by the Elterwater Green Slate Co., 
and the Tilberthwaite Green Slate Co., powerful and well equipped 
steam and hydraulic machinery has been erected for the purpose 
of raising the slate from the deep portions of the quarries, also 
self-acting and other tramways. Rock-drills and air-compressors 
have been introduced into the quarries of the Elterwater Company, 
and good results have been obtained by their use. Most of the 
slate obtained is of the bright sea-green colour which is so prevalent 
in the rocks of the volcanic series; but in some localities the 
chloritic colouring matter is absent, and the slate is grey or drab. 
Narrow bands of still lighter colour, sometimes almost white, pass 
through it, and occasionally these light and darker portions are 
contorted and intermingled together in an extraordinary manner ; 
they are also often broken up and shifted by miniature faults ; and 
not infrequently specimens may be found showing false-bedding 
and ripple-marking. 
In the uppermost beds of the volcanic series the fine ashes are 
mixed with water-borne sediment, and there are beds of moderately 
pure ash interstratified with beds of equally pure aqueous sediment. 
The more or less pure ash retains its characteristic colours of green 
or drab, but the sedimentary beds are much darker; in some 
places they have a purple tint, and in others are almost black. 
Some roofing slate is obtained from the dark beds, but generally 
the material is more suitable for flags. 
The beds of cleaved ash near the top of the volcanic series are 
more in number, they are also in most cases much thicker, and 
slaty cleavage extends over a much greater length along the outcrop, 
than in the slate-producing beds at the base of the series. In the 
latter the distance between the two extremities of the slate-producing 
area does not exceed seven miles, while in the former it measures 
thirteen miles. The beds in the upper part of the series are 
parallel to, and occupy ths same relative position with regard to 
