U CONTRÉE ENTRE BANGOR ET BETHESDA

Mawr * towards Cynichl' and Moelwyn '; and of Cwm-Orthin , near Ffestiniog, which I recommend ail walking tourisis to asceud, and to look ont for a séries of magnificent roches moutonnées , and blocs perchés below the raouth of the lake , which are besl se»»n looking down the valley. But I refrain from such descriptions, and shall content myself witha brief account ofNant Francon* and some of its tributary valleys y which show, in a striking manner, ail tbt familiar signs of glaciers.

R. 12. Between Bangor and Bethesda (of late sometinaes callôl Glan Ogwen) , the lower ground is more or less covered by ZM/f, through which hère and there bosses of glaciated rock protrude ; as, for instance, on the eastern flank of Moel-y-ci *, near Ponl-ycoetmor^, and in the neighbourhood of Bethesda.

South of the Penrhyn slate-quarries the valley narrows as \ve enter the Pass ofNant Francon , and the mountains rise grandly uo either side; on the left in a long steep-sided hill, whîle on the right the ridge is bold, irregular, peaked, and penetrated by tributary valleys. In the bottom, between Ogwen Bank and tlie fallsor Llyn Ogwen \ the river wanders through marshes and flat nieado\^s, which I often incline to think may at one time bave been damroeJ up on the north, to form a lake , at a spot not far above the slatequarries , where the Cambrian and Lingula grits , striking across the valley , hâve been ground by the old glacier of Nant Francon into roches moutonnées^ as perfect as any in Wales. Thèse are easily accessible on the left bank of the river, where I shali therefore describe them.

* Big Sands.

* Cynicht means a < basis » or ■ foundation; • but wtiy the word is apptied to this hil] I do not know,

*Moel is always applied to a round-topped hill. Mœlwyn^ «White Round Bill,* rr « White Hill. >

* Francon , or F francon , is believed to be a corruption of Avancon , bearers ~ « Beavers' Valley.» The river, often sluggish , winding through the alluvial flat, is jost the sort of water to bave been inhabited by beavers.

*Ct\adog. «Dog'sHiU.»

* Coetmor, probably a corruption of Coed Mawr. Pont-y-Coed Mawr^ Bigwood Brid;:^. ^ Ogof means a cave. Ogwen probably means «White Cave ; • but l do not know of as;

caverns , either white or black , in the neighbourhood. It may probably be appiicd t» tlie little gorge down which the white waterfall dashes.

CWM-CEUNANT. 581

From Ogwen Bank to the ground opposite Tyn-y-maes S for a distance of a mile , ail the low ground by the river is occupied by smoothly glaciated undnlaling rocks , marked by numerous smaller mammillations , and dotted with erralic blocks , chiefly of felspathic porphyry. The larger curved surfaces are especially prominent , because of the hardness of the grits , which are hère interstratified wilh softer slaty beds. The latter having been more easily worn away and reduced to a lower level , the grits are left standing ont in relief ; and are slrongly grovedy ail the striae running down the valley in a direction a little west of north. — Any one who will take the trouble of ascending Cwra-ceunant' will also find striœ in thq cwin.wuntnt. lower part of the valley *, running in the same direction ; and , what is more remarkable , on ice-worm Cambrian grits that form the shoulder of Bronllwyd*, at a higher level than the Penrhyn • slatequarries , well marked slriations follow the same course about 700 feet (213 mètres) above the river, probably intimating that at a certain period the ice of the glacier was hère at least of that height. This ridge is worlh the ascent were it for nothing more than the view, from such a foreground, of the great mountain recesses that once formed the sources of the glaciei\ In the middle the sharp cône of Y Tryfan ' rises like the fragment of a gf*eat waUy seemingly in- ^ ^'y'"" accessible although in reality it may be scaled without much diffîculty among the shattered blocks of stone that lie in strange confusion on its steepp western side. On the left of Nant Francon Ihere rises the long ridge of Pen-yr-Oleu-wen *, gradually increasing in Pen-yr-oieu-ww. height, and ending in the broken clifTs of Craig-yr-hysfa ^, and on the right are the recesses of Cwm-Bochlwyd •* and Cwm Idwal , the

* House in the Field , or Field-house.

* This helps to throw light on the manner of formation of some of the rock baiins that contain lakes.

' Ceunant^ «Closed Valley.»

* About half a mile W. S. W. of Pen-y-gareg. ^ ^Bron^ a breast; llwyd , grey. «Grey-breast.> *A promontory.

'* Three Peaks.

* Glow-worm Head , or Hill.

* Hounding Crag.

'* Pale or Grey Cheek. The name probably ought to be written Byrhlwyd , a grey he-^oat.

P«n-y-garcg.

582 PENRHYN ET CAPBL CURIG.

old parent'basins ofthe glacier j surrounded by the crags of Ihe two Glyders , so steep that in places they are inaccessible.

In the bottom of Nant Francon above Pen-y-gareg, the signs of the glacier , from the nature of the rocks , become less striking. The slopes are, however, hère and there sprinkled with travdM blocks y one of which , of large size , stands by the road et Pen-ygareg itself. Il is of feispathic porphyry^ and was probably dérive*] from the clifTs of Graig-yr-hysfa , or Cwra Idwal , from Iwo to thrce miles ofF. Others lie on the very crest of the ridge of Pen-yr-Oleuwen, one of which, on slaty hills about 2000 feet (610 mètres) abo^e the sea, is a block of feispathic porphyry nine yards in length, five high , and two in breadth (90 mètres cubes). Its weight must be about 180 tons. Between Tainewyddion * audMaes-Caradoc', by tbe road , the rocks are polishedj and grooved ; and opposite Ty-g^-n * an excellent example of a roche moutonnée rises in the midst of the alluvial flat, presenting, as is fréquent in such cases, its broken side down and its rounded side up the valley in the direction whence the glacier flowed.

Between the Penrhyn slate-quarries and Capel Gurig , fifleen tributary valleys branch from Nant Francon and the valley of Uyn Ogwen and Alon Llugwy. Eleven of thèse are on the west and south , and four on the east and north. The watershed in the Piass is at Wern-go-uchaf * near Llyn Ogwen , and it is easy to infer that wesi of this and Y Tryfan the high valleys of Cwm Bochlwyd and Llyn Idwal ^ both contributed a great part of the ice that ftoved do\c% Nant Francon. Between Llyn Idwal and Bethesda each of the wi tributary valleys in some way or orther tells that it was once tlie home Llyn cyifion. Cwm- of a glacicr. At Llyn Cywion • in Gwm-goch , and in Gwm-bual ' and " Gwm-ceunant, there are scraps of moraines y and erratic blocks; or striated surfaces , from some of which , on removing the turf, I found that the ice-smoothed slate still retained a glassy polish.

Tainewyddion et Maet-Canidoc.

Roches polies et striées.

Penrhyn et Capel Cnrig.

goch . Cwm-bual Cwm-ceunant.

Sarfaces striées,

blocs erratiques et

moraines.

' New Houses.

*Caradoc's Plain.

* White House.

* Upper Blacksmith's Copse.

" Idwal , a man's name.

* Chicken'8 Poil.

' Wild BuU, or Buffalo VaUey.

lYint Francon et ses Tollécs.