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On the northern margin these veins have been very productive, 
and on the south-eastern margin scarcely less so; but those on the 
southern and western sides, although perhaps quite as numerous, 
have yielded very little ore. One of the latter—a copper vein— 
may be traced for a distance of four or five miles, and at one part 
of its course, called White Stones, on the south-western flank of 
Skiddaw, where several other veins intersect or diverge from it at 
various angles, an immense mass of quartz has been thrown out; 
indeed, so great is the quantity, that a mining engineer with whom 
I once visited the piace, remarked that it appeared to be the home, 
or headquarters, of all the veins in the district. 
The mineral deposits occurring in the Skiddaw group of moun- 
tains, and in the rocks and veins just described, are of very varied 
character; they contain many rare and beautiful varieties, more 
probably than are to be found in any area of equal size in the 
United Kingdom, or even in Europe. ‘The deposits occur almost 
exclusively at the edges of the mountain area, and appear to be more 
closely associated with the intrusive masses and dykes of diorite, 
felsite, and gabbro, than with the granite itself; indeed, the central 
portion of the area has hitherto proved to be entirely barren. The 
prolific veins of the Caldbeck Fells area are in close proximity to the 
felsite, gabbro, and bastard granite on Carrock and Great Lingy, 
and the bearings of those that have yielded the largest quantities 
of ore are east and west, being nearly parallel to the longest axis 
of the intrusive masses of igneous rock. Owing to the position of 
these veins, lying as they do between the masses of igneous rock 
and the lower ground to the north, they must have received the 
drainage from the igneous rocks during the whole of the time that 
these rocks and veins have occupied their relative positions. Both 
the veins and igneous rocks probably owe their origin to the 
volcanic disturbances which took place during the Silurian period, 
and the early part of the Old Red Sandstone period. The opening 
of the fissures, now occupied by veins, no doubt gave rise to an 
upward flow and circulation of highly-heated water, charged with 
mineral matter of various kinds, which would be thrown down on 
the sides of the fissures when the temperature became sufficiently 
