Hughes — Geology of the Lake District. 349 



thickness of the beds. Also they must have taken place previous to 

 the deposition of the Carboniferous Eocks, as the great Scar Lime- 

 stone is seen up both sides of the valley, lying with an almost 

 horizontal line of junction upon the upturned edges of the Silurian 

 Eocks. If we have here an unbroken ascending series there must 

 be more than 10,000 feet of green slates seen in this valley ; but for 

 the reasons above stated the measurement must be received with 

 caution. 



These green slates pass up into a thin bedded shivery slate, often 

 breaking up when weathered into small wafer-like fragments. 

 These in turn pass up into more sandy slate, with calcareous bands 

 forming the base of the Coniston Limestone. The limestone has 

 here yielded only some obscure traces of fossils, being considerably 

 altered by its proximity to one of the Great Craven faults. There 

 would appear, therefore, to be a passage from the green slates to the 

 overlying Coniston Limestone, as we find that not only does the dip 

 of the two formations agree exactly, but that there are beds inter- 

 mediate in lithological character between them. The two formations 

 are seen holding their relative positions in several small sections to 

 the east of those last mentioned; but nowhere else in this neigh- 

 bourhood is the junction seen. 



The next section. No. II., is drawn due north and south, down the 

 east side of Eibblesdale, near Horton. The green slates are seen in 

 the bed of the stream called Douk Gill, which runs out from a 

 " keld " ^ on the east of the village. They dip at a high angle in a 

 southerly direction, and pass up into calcareous slates, full of 

 characteristic Lower Silurian fossils. These are the lower part of 

 the Coniston Limestone, and about 150 yards down the stream they 

 begin to turn up again, so that what we have here of the Coniston 

 Limestone has been preserved in a synclinal, broken at its west end 

 by a fault noticed by Professor Sedgwick ( Journ. Geol. Soc, viii. p. 49), 

 which cuts off the Coniston Limestone, bringing the green slates again 

 to the surface. The Lower Silurian rocks are not seen again on this 

 side of the valley, the country where they might be expected being 

 entirely obscured by Drift. 



Along the road north of Hardland's Plantation, and south-west 

 from that to Hardland's Barn, there is a tough grit, succeeded by 

 flags exposed in the quarry in Hardland's Plantation. These may 

 be seen undulating gently in many places west of Beckdale Barn, 

 and north-west of Eedding Barn. They are of no great thickness, 

 and are soon succeeded by more grits, which are seen along the road 

 north-west of Dove Cote, and also sticking out in ice-worn bosses 

 here and there to the south of Stanaber Barn. These grits and flags 

 are the lower grits (A.c. 2) with their subordinate flags, which are 

 therefore the equivalent of those west of Crag Hill Barn. 



Near Stanaber Barn the grits pass up, through alternations of flags 



1 "Keld" is the term applied to the large springs so common in limestone districts, 

 where the water collected in the pot-holes and crevices of the rock runs out a full 

 stream from a cave below. Prof. Sedgwick informs me that a similar word ("Kelda," 

 I think) is used to denote a similar phenomenon in Iceland. 



