DAKYNs: »;la('ial phenomena of wharfedale. 55 
rocks, there will be a stony deposit with but little clay ; where 
it comes from shale there will be much clsiy. 
It is quite impossible, as a rule, to separate the boulder 
beds from the sand and gravel, for the boulder beds, when 
stony, and when tlie stones are well rounded, approximate to 
gravel ; and. moreover, as the section of the Barden Reservoir 
shows, sand and gravel are sometimes intercalated in the midst 
of boulder clay. Consequently no general sequence can be made 
out ; but near Linton ^lill gravel certainly lies on the top of 
boulder clay, for there is a steep bank, the upper part consisting 
of dry gravel and the lower of wet clay, which throws out the 
water percolating tlie first ; but as there is no section to be seen, 
it is impossible to tell whether the gravel is a scratched boulder 
gravel or a water- washed gravel.* 
Near Park Bridge, over the Wliarfe, there is above the 
alluvial flat a bank of gravel, which though very rough and 
unstratified in some parts is on the whole distinctly stratified. 
It contains subangular blocks of Millstone Grit about three feet 
in diameter. This gravel continues some way up stream. 
Opposite the Lud Stream islands there is a gravel in a similar 
position and apparently of the same general character, but 
the section is not clean cut. It is surmounted by another bank 
of gravel (section also not good) apparently of the same character, 
but containing much larger subangular blocks of grit. The 
top of this gravel bank is 75 feet above the river, and thence 
there stretches a gently rising and undulating surface for about 
one-sixth of a mile to tlie foot of the hill called South Xab. 
This plateau may be all of gravel. 
On the left bank of Posforth Beck, a little below the first 
bend in the stream above its junction with the Wharfe, there 
is a section in true glacial drift. The material consists of angular 
debris of grits and limestones ; the blocks of the latter are well 
* Xote on tlie gravel near Linton Mills mentioned in my MS. of 1878. 
I have just learned from Mr. Percy Kendall that the gravel near Linton 
Mills, which was quite hidden by grass when I was siu-veying in Wharfe- 
dale, is now well exposed, and that it is, in his opinion, undoubtedly a 
glacial gravel.— J. R. D., March 0th, 1902. 
