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reduced, either by approaching the surface or by mingling with 
colder currents. The deposits first formed were probably at a higher 
level than any part of the surface of the Lake District, as it now 
exists, and have since been removed by denudation, together with 
some thousands of feet of rock, consisting of Silurian and Carbon- 
iferous strata, which at one time probably extended over the whole 
district. The many valuable deposits of ore found on high 
mountains, prove that these deposits must have been formed when 
the surface was at a much higher level than it is now. Of these I 
may mention Greenside, Roughtengill, Threlkeld, Dale Head, 
Goldscope, Yewthwaite, and Old Brandley ; the first named being 
two thousand four hundred feet above the sea. At Old Brandley 
there was a valuable deposit of lead ore at the ridge of the moun- 
tain,—one thousand four hundred feet above the sea—and extending 
downwards to a depth of about thirty fathoms. Below that point 
there was no ore found worth naming, although several long levels 
were driven, and extensive explorations made. 
Mr. J. Clifton Ward calculated from the size of the vacuities in 
the liquid cavities, of the quartz in the Skiddaw Granite, Eskdale 
Granite, Buttermere Syenite, St. John’s Quartz Felsite, and other 
granitic and granitoid rock; also in the vein quartz occurring in 
the central portion of the Lake District, that these rocks must have 
been formed, and the vein fissures filled, under a pressure equal to 
from twenty thousand to thirty thousand feet of rock. And further, 
that the water by which the quartz and other minerals were 
deposited must have been at a very high temperature. As the 
voleanic energy gradually decreased, the deposition of mineral 
matter would proceed to lower, and lower, levels ; and thus those 
portions of the vein fissures nearest the surface would be filled first, 
and the deep-seated portions more recently. The flow of thermal 
water was not confined to the vein fissures, but also accompanied 
the intrusive masses of igneous rock, and probably continued to 
find its way upwards, around the sides and through the joints of 
these rocks for a considerable time after they were solidified and 
partly cooled. Satisfactory proof of this has been obtained during 
the quarrying operations in the St. John’s Quartz Felsite at 
