C. E. De Ranee — Mineral Veins in the North-west Country. 65 



tion of 1200 feet. Both the lower plains are much covered with 

 drift, and the rock-surface at the sea-coast is often 50 feet below 

 low-water mark, steadily rising in one gradual inclined plain, 

 eastwards, or towards the Fells. 



The lowest plain is covered with peat often 20 to 30 feet in thick- 

 ness, resting on Cyclas and Scrobicularia Clays, which in their turn 

 overlie the Post-glacial and marine Shirdley Hill Sand, which rising 

 into a line of ancient Sand Dunes along the landward edge of the 

 peat at the base of an ancient cliff of Boulder-clay bounding the 

 second plain, in parts of which deep valleys have been entirely 

 cut in the glacial drift, as the Eibble valley at Preston ; and in other 

 portions the Boulder-clays and interbedded sands and shingles have 

 been re-excavated out of old Pre-glacial valleys. 



Pendle range. — Between the Wigan and Blackburn coal-fields 

 occurs a tract of elevated table-land, consisting of Mill stone -grit 

 more or less covered with peat and Boulder-clay with erratic stones, 

 forming Anglezark, Withnell, Eivington, and other moors, with an 

 average elevation of more than 1000 feet. This area, which has 

 been brought up by great faults, is drained on the south by the river 

 Douglas, which traverses the Wigan coal-field, and falls into the 

 Eibble, whose tributary, the Darwen, receives the Eoddlesworth, 

 which drains the northern portion of the moors. This latter river, 

 however, is in great measure absorbed by the Liverpool waterworks, 

 and artificially carried south. 



In making the "bye- wash" of one of the reservoirs for these works, 

 near Lower Whitbank, Tockholes, on the Eoddlesworth, a lode of 

 galena was struck, ranging W. 25 N. Specimens of the ore were 

 shown me by the lord of the manor, consisting of crystallized 

 sulphide of lead of a bluish-grey colour, the back of the lode being 

 quartz. The rocks in the nearest section I could find consisted of 

 the basement-bed of the third (Millstone) Grit, dipping at 70° to 

 the N. N. E., resting on Black Shales, containing "bullions," coated 

 with thin seams of coal, with Sigillaria markings, dipping N. 30 E. 



The hill-side, above the lode, dips with the beds towards the river 

 at 7°, the lode, which appears to be in a fault, nearly corresponding 

 in direction with the strike of the beds, running at the bottom 

 of the valley, parallel with the stream. It is clear that under these 

 conditions, all water falling upon the hill-slope above percolates into 

 the porous sandstone, and will be intercepted by the fault, which, if 

 consisting of an open fissure, would tend to be filled by any substance 

 that the water could mechanically remove, or chemically unite with, 

 from the grit and sandstone above. 



Mr. W. Wallace, in his admirable work on Alston Moor, which I 

 found invaluable when examining that district, gives four general 

 laws governing the distribution of lead : — 



1. That the quantity of water in circulation below the sximmit of a 

 mountain, is "in invei"se proportion to the depth from the surface, 

 and in direct proportion to the distance from the watershed." 

 Therefore, the greater the depth, the less the quantity ; the further 

 from the watershed the more the water. 



VOL. IX. NO. CIV. 5 



