OF THE DISTRICT. 
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once larger than at present, fed from an immense area of dry rocks which 
absorb the rain and yield a part of their stores to this elevated lake. 
Malham water is on the line of the North Craven fault, overlooked 
on the north by the limestone ranges of Hardflask and Fountains fell, 
while from below it rises to the south the depressed band of the same 
limestone. The natural exit of the water is in this direction, as a super- 
ficial channel distinctly shews ; but instead of following this channel, 
to fall in a mighty cascade over the tremendous precipice of Malham 
Cove, the water sinks into the open-jointed limestone rock, and bursts 
forth in a full and perpetual stream at its foot. This is the Aire ; it 
is speedily augmented by a stream from the cleft rocks of Gordale and 
other small branches, and flows south through an undulated country 
till its valley opens into the broader and more level regions of Craven. 
Here it receives on the right bank the water of Otterburn, running 
to the south-east ; this course after some flexures the main river assumes. 
Below Gargrave it is augmented by a considerable stream from the north, 
and in its long course to the south-east other small rivers and brooks 
swell its waters to a considerable amount. 
Airedale commences at Malham 680 feet above the sea, 570 feet 
below Malham water, which may be considered its source ; between 
Malham and Skipton there is a descent of 300 feet, from Skipton to 
Leeds about as much. The valley is nowhere remarkably contracted 
in its course through the Craven shales and black limestones from Mal- 
ham to Skipton, but at Kildwick, Keighley, Shipley, Calverley, and 
Bramley, the millstone grit rocks narrow its dimensions. 
Besides the remarkable origin of the principal stream of water we 
must observe the exact coincidence of the line of Airedale, prolonged 
in the Otterburn branch, with the western portion of the Craven fault. 
On the north of this line from Kirby Lonsdale to Skipton is an elevated 
country, to the south of it the whole region is depressed ; the north side 
of Airedale is higher than the south side, and it appears to me that 
the direction of this valley is really a consequence of the direction of 
the Craven fault. 
Y 2 
