﻿Yol. 6 1.] BLEA WYIE BEDS IN NORTH-EAST YORKSHIRE. 451 



of plants in a vertical position. No other fossils were found at 

 this horizon west of Salt wick Nab. 



(3) Sandsend and Kettleness. 



In the Sandsend alum-works the junction is very clearly shown. 

 The Dogger is here represented by some 3 feet of impure ironstone, 

 geDerally resting directly upon the Alum-Shale without any pebble- 

 bed ; but, in one or two places, a few pebbles are seen. About a quarter 

 of a mile farther, at the eastern end of the long tunnel, the Dogger 

 is completely absent, and sandstone of the usual Estuarine type 

 rests directly upon the Alum-Shale. 



Prom this point to Kettleness the junction runs close to the top 

 of high cliffs, and is quite inaccessible ; but, at one point near the 

 middle of the long tunnel, sandstone may be plainly seen resting 

 in a hollow in the Lias. 



Immediately east of the shorter tunnel a very clear section is 

 exposed ; the succession is as follows : — 



Thickness in feet. 



Very false-bedded yellow sandstone. 



Pebble-Bed 1 



Ironstone 1 



Alum-Shale. 



The Pebble-Bed is here much thicker than usual, and almost 

 merits the name of a basal conglomerate. The most noteworthy 

 point is that the ironstone-band is below the Pebble-Bed, and 

 must therefore belong to the Lias. Here, again, Estuarine Sand- 

 stone rests directly upon the Lias, with only a pebble-bed at the 

 base, and true Dogger is absent. 



All over this district the false bedding of the sandstone is very 

 remarkable, and indicates the prevalence of shallow water 

 and strong currents. 



(4) Boulby Cliff. 



In the large alum-quarries of Boulby Cliff the Dogger is very 

 well displayed, and shows some interesting features. At the western 

 end of the easternmost excavation the following section was 

 measured : — 



Thickness in feet inches. 

 Massive, very soft, pinkish-white sandstone. 



Oolitic ironstone 1 



Conglomeratic roek, with white fragments 2 



Concretionary ironstone 1 



Soft black clay 3 



Black carbonaceous shale 6 



Nodular ironstone 1 



Alum-Shale below. 



The rock which is described above as a 'conglomerate' is most 

 peculiar. It is a ferruginous oolitic rock, with black and white 

 fragments, and a few very badly-preserved fossils (apparently lamelli- 

 branchs, among which Astarte alone is distinguishable). 



2k2 



