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also occasional grains of magnetite and apatite. This rock is 
generally coarsely crystalline, but sometimes fine grained. 
The hornblende picrite of Little Knot is a coarsely crystalline 
rock of a dark olive-green colour. It is composed largely of horn- 
blende; but it also contains small quantities of quartz, felspar, 
iron peroxide, epidote, apatite, and calcite. It forms an oblong 
mass, about six hundred yards in length, by forty yards in width, 
and extends from the ridge of Little Knot, at the northern end of 
Longside, down nearly to the bottom of Southern Dale. There 
is also a large mass of hornblende picrite of like nature exposed 
in Hause Gill, a tributary of Dash Beck, a little to the north of 
Dash Farm. 
On the Dodd (Skiddaw) there are several dykes of Mica-trap. 
They consist chiefly of felspar and mica, with a little quartz and 
hornblende, also some calc spar in cavities. The felspar is 
generally much altered. 
Two small masses of diorite, probably portions of dykes, are 
exposed at Threlkeld Mine, in Gategill, Blencathra, where they 
have been cut into by the stream at the bottom of the gill. A 
slender dyke of similar character occurs at Robin Hood Mine, 
Bassenthwaite ; the latter is about half a mile in length, and from 
three to six feet in width. 
The Skiddaw group of mountains is intersected by an important 
fault, which extends through the depression occupied by Winder- 
mere, Rydal and Grasmere Lakes, thence through Dunmail Pass 
and the Thirlmere Naddle and Glenderaterra Valleys. In Skiddaw 
Forest it appears to bifurcate, the eastern branch passing along the 
valley of the Caldew, and the western branch along the depression 
occupied by Dash Beck, thus dividing the Skiddaw group into 
_ three sections of nearly equal size. The mountain mass is also 
flanked on the south by the great fault which forms the boundary 
between the Skiddaw Slates and the volcanic rocks, and on the 
west by the fault which passes through the valley of the Derwent. 
The outer portion of the mountain area is much cut up on every 
side by mineral veins, of which there are two sets, one having a 
prevailing east-and-west, and the other a north-and-south bearing. 
