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the W.N.W. In fact, while the fissure — although its sides are 

 irregular — remains apparently the same, the ore, lying between 

 walls of solid limestone, is twenty fathoms below the top of the 

 rock at one end, whilst it is level with the top of the rock at the 

 other end. 



After the main fissure is passed, branches of ore break off in two 

 directions, one trending N.W, to N., and the other trending nearly 

 south. 



These mines were discovered in 1851, and have now been in 

 working for thirty-four years ; and during this period from ten to 

 twelve million tons of ore have been extracted. They are very 

 irregular in the quality of the ore, and the shape and direction of 

 the pocket is very uncertain. The best of the ore in the centre of 

 the big mine runs up to 63 7o of iron oxide, or 90 7o of oxide of iron, 

 whilst the bulk of the ore to the S.S.E. of the mine does not 

 contain more than 70 to 80 %• Where the mine branches off 

 into two different directions (see map), the ore in places falls in 

 per centage as low as 60 % oxide, and here there is a large per 

 centage too of manganese. 



The limestone continues apparently free of ore for about half a 

 mile due west. In all this ore-bearing rock the clay occasionally 

 seems glazed with ore, but in no case has any discovery of work- 

 able quantities been made in the clay. The Hmestone then dips 

 under the New Red Sandstone, and of course all hope of iron ore 

 ceases to exist. 



To the south of these mines we find, as we approach Furness 

 Abbey, the New Red Sandstone again overlying the Mountain 

 Limestone. But at a few hundred yards past the Abbey the 

 Mountain Limestone again reappears, and half a mile further 

 south, the ore-bearing limestone is met with. Here two mines are 

 working — Yarlside, nearest to Furness, and south of this, Stank. 

 And here too a remarkable phenomenon presents itself 



Near the junction of the two mines the Yoredale Shale appears, 

 the Mountain Limestone dipping under it ; and at Yarlside the 

 ore is found nearest to the surface in limestone rock. At Stank 

 the following strange circumstance occurred. 



