49 
slate metal may be traced along the outcrop, from Bouldering End, 
by Rigg Head and Honister, to near Scarf Gap, at the head of the 
vale of Ennerdale; beyond these points they no doubt have an 
extension westwards towards Egremont, and eastwards towards 
Mellfell, but in these portions cleavage is very slightly developed ; 
indeed, the true slaty cleavage occurs only between the igneous 
masses of St. John’s Quartz Felsite and the Ennerdale Syenitic 
Granite, and,it is probable that the increased lateral pressure 
caused by the irruption of these masses may have assisted materially 
in producing the requisite amount of cleavage. Trials have been 
made at several points along the outcrop of the beds, but the slaty 
cleavage is insufficiently developed, except at Rigg Head, Honister, 
and Dubs. A little slate has been obtained from the quarries at 
Castle Crag and Dubs, but all the other trials appear to have been 
unsuccessful. The two beds are from fifty to sixty yards apart, 
and the lower or northern one is about sixteen feet in thickness, 
its upper and under surface being clearly defined. The upper or 
southern bed is much thicker, but not so well defined. The former 
has been worked extensively in the quarries at Honister Crag, and 
the latter at Yew Crag, on the opposite side of the pass. Honister 
Crag has been pierced by ten, and Yew Crag by six levels, some 
of which are from one hundred to one hundred and twenty fathoms 
in length. The united length of the levels on both sides of the 
pass is near three miles; and the tramways in use in these levels, 
and from the levels to the head of the pass, where the slate is 
discharged, including the tramway to Dubs quarry, measure about 
six miles. 
The beds of ‘slate metal” from which the slate is obtained in 
these quarries is composed chiefly of fine ash, but at irregular 
intervals layers occur that are much coarser, and occasionally 
fragments of older rock of considerable size are found embedded 
in the fine ash. Near the top of the upper or southern bed there 
is a thin band or stripe of very fine and compact ash, of a pale 
purple colour, varying in thickness from three-quarters of an inch 
to one-and-a-half or two inches. The lower edge of the band is 
more clearly defined than the upper edge, the material is also finer 
4 
