‘Ash-bed’ and ‘ Bala Limestones.’ 347 
into its present position. We were now at the summit of the hill ; 
and, as the too short day faded into twilight, we looked up the ‘ reach’ 
of the valley of the Ceiriog, which stretches from the New Inn to 
Pontymeibon, and could distinctly trace on the surface the rugged 
escarpments of the three ‘ Ash-beds’ and the three Limestones, with 
the depressions between each, which serve to mark the place of the 
softer intervening Shales. This order of the strata may be taken 
as a type of this portion of the Bala or Llandeilo Group as it is 
developed in North Wales. In South Wales, where the Bala Lime- 
stone loses its distinctive features, the Trap-rocks also lose their 
massiveness ; and the same is the case at Shelve, where the Ash-beds 
occur in numerous layers interstratified with flags and shales. We 
noticed the correspondence which each side of the valley bears to 
the other, Ash-bed, Limestone, and Shale answering each to each on 
either side, like Coleridge’s ‘Roland and Sir Leoline.’ 
* 
Like cliffs which have been rent asunder; 
But neither time nor frost nor thunder 
Will wholly do away, I ween, 
The marks of that which once hath been. 
They stand aloof, the scars remaining. 
* * * 
This is not a mere valley of erosion; for in the dipping of the 
strata on the one side to the NE., and on the other to the SE., we 
at once perceive that it owes its origin to a crack in continuous 
strata, made in the process of upheaval, the said crack having been 
since widened by time and action of water, which weareth away 
the stones. 
The day was closing, so we descended rapidly, past the kilns 
where the stone is burnt for lime, past the Shales overlying the 
Limestone, past the third or Hirnant Limestone, and, recruiting 
our strength at the New Inn, heavily ballasted with fossils, we 
wended our way up the steep hills of ‘ Wenlock Shale’ which divide 
the valleys of the Ceiriog and the Dee. The lights of the town of 
Llangollen peered through the gloom as we gained the summit, and 
before long we were there. And now, kind reader, having brought 
you safely to a habitable and hospitable place, we thank you for 
your company, and bid you good-night. 
ABSTRACTS OF BRITISH AND FOREIGN 
MEMOIRS. 
a 
[The Report of this and the following Paper, read before the British Association 
at Bath, Sept. 1864, has been unayoidably postponed until this month.] 
1. On THE BovutpErR-ciay or East Yorxsuire, By J. Lecxensy, F.G.S. 
ee author pointed out the existence of the evidence of glacial 
conditions in the clays, sands, and gravels which overlie the 
Secondary strata of Yorkshire in its northern and eastern portions, 
especially around Whitby and Scarborough, in the Moorland Valleys, 
