35^ X^Elineraloss. 



and also in depth — ' some creeping out ' at the surface and 

 others lying at an unknown distance below it. 



Iron. — The mineral of the district next, or perhaps equal 

 in value to coal, is iron, the ore of which metal is found in 

 great abundance in Furness, and in West Cumberland, in 

 the district lying immediately north of Egremont, and also 

 in more limited quantity, in Millom, Eskdale, and other 

 localities. In 1857, the iron mines in Low Furness yielded 

 ore to the amount of 560,000 tons, and in the same period 

 there were drawn from the Cumberland mines about 198,000 

 making the yield in the whole district, say, 758,000 tons. 

 It occurs chiefly in the form of a red oxide, and is deposited 

 in masses, varying greatly in dimensions, in the cavities of 

 the limestone rock of the country. It is occasionally found 

 close to the surface, but more frequently at considerable 

 depths. Another form in which iron occurs in the district 

 is that of sulphuret, or iron pyrites. This is nowhere worked 

 for profit now, though it is widely diffused throughout the 

 great green slate and some other formations, and large quanti- 

 ties exist in the waste heaps of the Coniston mines. It is found 

 also in the carboniferous series, amongst the Cumberland 

 coal measures, especially at Harrington, where it was lately 

 used in the manufacture of certain chemicals. Iron occurs 

 also as a magnetic oxide, and in various other combinations, 

 the most interesting of which is that known by the popular 

 name of wad, blacklead, or plumbago. This is found only 

 in Borrowdale, and is one of the multitude of valuable 

 minerals deposited in the green slate-rock, in which it lies in 

 irregular heaps or ' sops.' Statistics of this mineral are not 

 procurable, indeed, the wad mine has not been worked for 

 some years, but has recently been re-opened. It is generally 

 known at the present day that the name blacklead is erro- 



