112 RIVERS. 



The blocks are very often perched ; show no marks of abra- 

 sion; no other drift matter is with them; they are collected 

 sometimes into small groups; and they may be regarded as 

 uplifted and floated by ice, and dropped on surfaces which had 

 been swept by currents clear of other loose matter. 



In lower ground, to the southward, westward, and eastward, 

 the slaty blocks have been carried very much further; in this 

 case they are no longer solitary, but mixed with other sorts of 

 detrital matter, and occasionally show marks of attrition in 

 water which they never do on the high limestone hills (see the 

 Lithograph). 



The river quits the elevated region which is north of the 

 Craven fault at Settle, the limestone country here dropping 

 suddenly down 1000 feet. Long picturesque cliffs mark the 

 line of this singular and enormous displacement. Of these 

 great scars, Giggleswick, on the west, is perhaps the most re- 

 markable ; Castleber, above Settle, is also a fine mass of rock, 

 worth ascending. At the foot of Giggleswick Scar is a small 

 spring, subject to uncertain fits of rising and falling, a phse. 

 nomenon which the stone basin into which it flows renders 

 apparent. Variable pressure on the water, derived from a 

 curved or siphonal passage underground, is the principle on 

 which explanations have been offered for this and other such 

 springs by Gough and other writers, and the effect may be 

 copied by artificial experiments. In dry seasons it is useless to 

 wait for the performance. 



The course of the river is southward by Hellifield Peel (an 

 ancient rural tower of defence) and Gisburn, where still the old 

 breed of almost white cattle which formerly roamed in the forests 

 of the north of England may be seen. At Bolton by Bolland, 

 an ancient mansion which once sheltered Henry VI., caverns 

 appear in the limestone. A little further down the river is the 

 admired ruin of Sawley Abbey (Cistercian, 1147). 



The Kibble now becomes for a few miles the boundary be- 

 tween Yorkshire and Lancashire, leaving on the Lancashire side 



