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pointed out to the Carlisle Scientific Society on our Whit-Monday 

 excursion to Melmerby in 1880. The vein there coincides, as 

 such veins nearly always do, with the line of a fault ; and right 

 and left of the line of the fault the limestone adjoining the vein is, 

 in great measure, replaced by rock of a more or less silicious 

 nature, which, in its most highly-altered portions graduates into 

 pure vitreous quartz. In the less-highly-altered portions of the 

 vein the bedding and the traces of fossils are distinctly visible. 

 Several other veins of this nature are to be found elsewhere in 

 Edenside : one set occurring at the Scordale Mines near Roman 

 Fell ; while another equally well marked set occurs close to the 

 head-waters of the Eden near Hanging Lunds in Mallerstang. 

 Here the limestone adjoining the veins has been altered to a width 

 of nearly fifty feet at one place into a hard silicious quartzite, 

 which, nearer the centre of the vein, graduates into pure vitreous 

 and crystalline quartz. Like the Hsematite, the Quartz in this 

 case exercises a well-marked selective influence ; and, while the 

 limestone fragments of the fault-breccia in each case are more or 

 less metamorphosed, the accompanying fragments of sandstone 

 and of shale remain in their original condition, just as do the chert 

 nodules in the case of the Haematite deposit at Harcla, already 

 mentioned. 



All these veins contain Pyrites, and at least traces of Copper — 

 generally in the form of either Chalcopyrites, or else in that of 

 Chessylite or of Malachite. Other minerals are rare. 



Nearly all the metalliferous veins of the Lake District are quartz 

 veins, which is probably due to the fact that, as veins, they date 

 from Precarboniferous times, and that, once formed, they have 

 acted as upward vents for thermal springs from the date of their 

 formation down to the time when they received their latest deposits 

 of ore. No one can look at the spongy quartz — so light and 

 cellular that it will almost float — that is found in the Caldbeck 

 Fells and elsewhere, without feeling assured that its present 

 condition points to a long and complex series of changes it has 

 undergone in the course of the long geological periods that have 

 elapsed since its formation. 



