16 
ON THE GEOLOGY OF CRAVEN. BY W. H. DALTON, OF H. M. 
GEOLOGICAL SURVEY. 
(communicated by PERMISSION OF THE DIRECTOR.) 
The title of this Paper would have been given more 
correctly as the Geology of Airedale, for I do not propose to 
bestow more than a passing notice on any rocks not occurring 
within the basin of the Aire. I must state that, as the 
Memoirs of the Survey will contain full descriptions of all 
the phenomena connected with the geological structure of 
the districts which they illustrate, the regulations prohibit 
any forestalment of the Memoirs, unless some very important 
fact is discovered, the withholding of which till the publica- 
tion of the Memoirs would be detrimental to the progress of 
science. As nothing very new or startling has been dis- 
covered in Airedale, my remarks must of necessity be limited 
to such general observations as wiU not lessen the value of 
the forthcoming Memoirs on the district. 
The basin of the Aire consists of three districts of distinct 
lithological, and consequently physical, aspects. From the 
source of the Aire in Malham Tarn to the lofty precipice 
of Malham Cove, extends a plateau of limestone, falling 
gently to the north, and intersected by several deep rugged 
gorges. The surface of the southern part consists chiefly 
of bare rock, whilst in the Silurian area to the north extensive 
deposits of coarse boulder-gravel, almost entirely composed 
of limestone, form large pastures of coarse grass, through 
which the larger boulders protrude. 
South of Malham we have a depressed area of undulating 
ground, consisting of limestone, with numerous intercalations 
of calcareous shale, the whole hel^g extremely contorted, 
denuded and obscured by drift. Above the general level of 
this tract rise three hills, capped with MiUstone Grit, viz., 
Eye Loaf Hill, between Malham and Settle; The Weets, 
