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CUTTRISS : NOTES ON THE CAVES OF YORKSHIRE. 
acknowledge the valuable assistance afforded by many friends in 
the sometimes difficult work of exploration, without whose co-opera- 
tion the Avork in many cases could not have been accomplished. 
Geological Division and Formation of Caves. 
The ceaseless action of the sea on the chalk cliffs of Flamborough 
Head has resulted in large chambers and tunnels being formed, 
which, though interesting in their way, hardly come within the 
scope of these notes. Again, the Oolitic limestones lying to the 
north of the Vale of Pickering contain a few small caves and 
underground watercourses, but they are of no great interest if we 
except the Kirkdale Cave, made famous by the investigations of 
Dr. Buckland in the early part of the present century, and which 
gave occasion to the publication of his " Reliquiae Diluvianae." It 
is in that part of the county lying to the west of the great central 
plain, where the Carboniferous limestones and mountainous character 
of the country make it particularly suited to the formation of 
caverns and underground watercourses, that the largest number and 
finest examples are found. Round Ingleborough and the neighbour- 
ing mountains they are an ever-present feature of the landscape, 
some having the form of open chasms between 300 and 400 ft. 
deep, while others have ramifications underground known to extend 
for over half a mile from the entrance. 
The base of the hills forming the Pennine Cliain — the backbone 
of England — is composed of the Silurian slates and grits, the oldest 
rocks in Yorkshire. Upon their upturned edges has been deposited 
a mass of hard, compact limestone, the Carboniferous, Mountain, or 
Scar Limestone, as it is variously called. This forms an extensive 
plateau, through which the valleys have been cut, having a gentle 
dip towards the north-east of from 1 to 5 degrees, and thinning out 
in the same direction. Towards the west it has been cut off by the 
Dent Fault, its furthest extension in that direction being on the 
Leek Fells. Southwards it is terminated abruptly by the Great 
Craven Faults. From Iiigleton the main line of fault runs through 
Clapham and Austwick to Settle, forming the Giggleswick Scars. 
Thence it continues in a due easterly direction by the Attermire 
