96 DESCRIPTION OF THE COAST. 



in uneven, thin, white sandstones, alternating with black micaceous shale, 

 and in ironstone, which is traversed by a white aluminous earth of the 

 same nature as that previously noticed at White Nab, near Scarborough. 

 A particular account of all these plants will be found in the latter part 

 of this work. The dogger bed beneath them is a very singular layer of 

 inconstant appearance, and varying substance. Sometimes, and indeed 

 generally, it is a very irony nodular sandstone ; but in other places, and 

 particularly towards Whitby, it contains small pebbles of limestone, 

 glassy quartz, blende, small red ironstone, white felspar, porphyry en- 

 closing glassy quartz, scoriform greenstone, red oxide of iron, &c. 

 Towards the bottom, I have, in some places, seen it full of limestone 

 pebbles, (lias ?) and under these a layer of large and small ironstone 

 balls. 



The upper lias shale may be well examined in the cliffs and on the 

 scars, at low-water. Many remarkable and characteristic fossils may be 

 here collected, especially the belemnites tubularis of Young, ammonites 

 Mulgravius, &c., nucula ovum of Sowerby. 



The great dislocation before mentioned, which depresses the strata 

 on the north side of Whitby, extends a considerable distance up the 

 valley of the Esk. Its effects are very remarkable at the sea side. On 

 the south side of Whitby harbour, a part of the cliff is composed of the 

 upper alum shale, and this rock extends far into the sea, making broad 

 level scars at low- water ; but on the north side of the water is a cliff of 

 sand-stone, and a beach of sand. The exact amount of the depression 

 occasioned by this fault cannot, perhaps, be determined ; but I estimate 

 it to be not less than one hundred and fifty feet. 



Between the cliff which supports Whitby Abbey j one hundred and 

 fifty feet above high^water, and that where the Lyth alum works are 

 established, one hundred and ninety feet, the strata are depressed by the 

 before-mentioned fault, so that the lias shale is almost wholly below the 

 level of high-water, and the cliffs are composed of sandstone and shale, 

 covered by a very abundant deposit of diluvial clay and pebbles. The 



