•58 
DAKYNS : (GLACIAL PHENOMENA OF ^^^ARFEDALE. 
valley, concealed from sight by superficial detritus, drift, and 
alluvium ; and that our boulders were thence derived. This 
makes everything simple ; and the thickness it allows to the 
limestone is quite equal to the thickness seen in Ribblesdale. 
In conclusion, let me say that thus far the Glacial phenomena 
of Wharfedale lend no support to the theory that the whole 
country was over-ridden by an ice cap descending from the 
pole, for there is no evidence here of foreign ice ; but everything 
is in favour of huge confluent glaciers, or ice sheets (if that term 
is preferred), of home-made ice. 
Nidderdale, too, supports the same conclusion : there are 
no foreigners there at all. 
Large gravel mounds of an older date than the river terraces 
occur both above and below Pateley Bridge. These may be 
Eskers. They reach a height of between 400 and 500 feet above 
the sea. 
