174 YORKSHIRE NATURALISTS IN LOWER WENSLEYDALE. 



he has placed in a room at Bolton Castle, thus constituting a small 

 but valuable museum. Mr. Horne attributes this cave to a period 

 long before that of the Romans. The specimens were examined 

 carefully and with great interest by the party, and the explanations 

 of the leader were evidently appreciated. The object of this 

 excursion v/as to study those beds of limestone, shales, and sand- 

 stone which the great Yorkshire geologist, Professor Phillips, has 

 named the 'Yoredale series,' and many opportunities were offered 

 during the day of effecting this purpose, as well as of studying the 

 physical geology of one of Yorkshire's finest dales. Perhaps a 

 section of the beds carefully taken by Mr. Rodwell, engineer and 

 agent of the Keld Head Lead-mines, which he has kindly allowed 

 to be used, will not only simplify present remarks, but, as being 

 thoroughly authentic, will be most useful for future reference, as it 

 shows the relative position and the thickness of the beds so well. 



SECTION OF STRATA TAKEN AT THE KELDHEAD MINES, 

 WENSLEYDALE. 







ft. 



in. 







ft. 



in. 



2 



Grits 



36 



0 





Undersett Limestone 







o 



Plate or Shale 



6 



0 





(fish remains) ... 



13 



0 





Grit 



36 



0 





Plate or Shale 



27 



0 





Hasle Grit 



6 



0 





Soapy Gritstone ... 



21 



6 



Plate and Girdles... 



24 



0 





Plate or Shale 



27 



0 





Stone Plate or Shale 



6 



0 



ui 



Thin Limestone ... 



9 



0 



hJ 



Coal ... ... 6 in. 



to 3 



6 



W 



Preston Grit 



36 



0 





^Grit and Shale 



66 



0 



SER 



Plate and Shales ... 



6 



0 





/^Crow Chert 



19 



0 



Limestone (fossiliferous) 



58 



0 





Crow Limestone 



16 



0 



W - 



Sandstones and Shales ... 



60 



0 





Grit 



36 



0 



Keldhead Limestone... 



64 



0 





Plate or Shale 



18 



0 



<l 

 Q 



Flagstone (Gilbert Scar)... 



18 



0 



K 



Girdles and vShales 



12 



0 





Plate or Shale 



II 



0 





Main Chert or Red Beds 







0 



Gritstone and Shale 



53 



0 



S 



(Harmby Quarries, 









Grit and Limestone 



13 



0 





fish remains) ... 



42 



0 





Plate and Shale ... 



24 



0 



Thin Limestone ... 



7 



0 





Ash Bank Limestone... 



42 



0 



< 

 Q 



Shales (Black Quarry) ... 



7 



0 





Shales and Sandstones 





w 



Main Limestone (Ley- 









alternately 



60 



0 



o 



burn Shawl) 



63 



0 





, Six Fathom Limestone 



61 



0 





Giit 



30 



0 





'Shales and Limestone 



30 



0 





Plate or Shale 



24 



0 



11 



Limestone... 



90 



0 





Sandstone and Coal 



16 



0 





Grit (West Burton) 



24 



0 





Plate or Shale 



28 



0 



0 E 



Limestone (thickness not 





known). 



As Mr. Davis has so well observed, the alternations of limestone, 

 shale, and sandstone in the Yoredale rocks indicate repeated changes 

 in the level of the land. At one time the water was deep enough 

 for the existence of the animal forms of life which originated the 

 limestone ; at others, the mud, brought from some adjacent land, 

 formed accumulations represented by the shales, probably in much 

 shallower water. The sandstones again point to extensive shore 



Naturalist, 



