DESCRIPTION OF THE COAST. 
76 
stone fossils which abound near the spaw at Scarborough, and in the 
cliffs of Holderness ; sandstones from the neighbouring moors lie on the 
cliffs between Scalby and Cloughton Wyke; and the chalk rocks of 
Flamborough have been scattered in fragments through the clay cliffs 
from Bridlington to Hornsea. The remarks on page 21, as to the com- 
parative degree of attrition of the boulders, are applicable to the whole 
coast of Yorkshire. The largest masses are always observed to be 
granite, mica slate, greenstone, or mountain limestone. Of these large 
fragments, which have fallen from the ruined cliffs, may be seen at 
intervals near the low-water mark, opposite Dimlington height, under the 
Danish dyke, on the summit of the beacon cliff at Flamborough, on 
the shores of Filey, Scarborough, Robin Hood’s Bay, Skinningrave, and 
Saltburn. It is not even uncommon to see many such boulders together, 
each weighing perhaps a ton. 
It is difficult to assign the native repositories of the beautiful agates, 
heliotropes, and jaspers, which are found on the shores of Holderness, 
Speeton, and Scarborough, after the wintry storms have caused the fall 
of some portions of the diluvial cliffs. They are probably all productions 
of trap rocks, possibly derived from the hill of Kinnoul and other amyg- 
daloidal basalts of Scotland. The question as to the nature of the 
beautiful dendrizations in moss agate remains unsettled ; for Dr. M‘Cul- 
loch’s ingenious chemical experiments leave doubts on their vegetable 
origin, which botanical investigation has not removed. Jet, another 
interesting product of this diluvium, may be traced to the neighbour- 
hood of Lyth, where considerable masses of it have been obtained from 
the cliffs of alum shale. It also occurs in other parts of the lias series, 
rather frequently in the lower shale near Skinningrave, generally in 
connexion with fossil wood, of which it forms the external layers. 
Seams of it also divide sandstone blocks in Hawsker bottoms. Magnetic 
sand (oxydulated titaniferous iron) occurs in great plenty on the shore 
where diluvial cliffs are exposed to rapid waste, or their disintegrated 
materials are retained in some sheltered bay. It is particularly abun- 
dant at Scarborough and near Hilston in Holderness. 
