241 
The following diagrammatic section will render plain 
what I conceive to be the relation of the beds. 
I mentioned above, that at the White Force the "Whin 
overlies a bed of altered Limestone ; in some places, however, 
a bed of baked Shale intervenes between the WhinsiU and 
the altered Limestone ; and the specimen I sent to Mr. Green 
is from this band at the White Force. 
Before closing, I would like to say a word on the term 
Sill." This term simply means bed or layer, as we say a 
bed of coal ; it is the usual word for bed in the North. 
They talk of Grit SiUs as well as Whin Sills. They say 
Whin Sill, because the Whin so generally lies horizontally, in 
a bed-like form, between the other beds. The word " Sill,'* 
though confined in this use to certain parts of the country, 
is the word familiar to all in the term window sill." In 
parts of Lancashire they call the rock over a coal-seam the 
*' Eoof," and the rock below it the Sill Rock." 
The first part of the name, Falcon Glints, indicates the 
crag as an abode of falcons. The word " clints " is probably 
expressive of the ringing sound made by the bits of broken 
whin when struck as one walks over them. In parts of 
Westmoreland ground covered with similar ringing fragments 
of limestone is called " clinty ground." 
Postscript — Since my visit to Teesdale in November, 1876, 
the suggestions I then made of there being a bottom to the 
Carboniferous system in that dale has been completely 
verified by Messrs. Gunn and Clough. See their paper on 
the subject, read before the Geological Society of London, 
and Mr. Gunn's paper, read before the British Association at 
Plymouth. 
Since writing the above paper I have had another oppor- 
tunity of seeing the Pencil Beds. While I still think them 
more like Skiddaw slate than anything else, where I first 
saw them, yet, in other spots they are more like the Pale 
