334 Messrs. W. Phillips and 8. Woods on the [Noy. 
resemble those of Moel Shabod, that we cannot hesitate in refer- 
ring them to the same era, and here also the direction of stratifi- 
cation is in the plane of the slaty structure. 
In our walk to the Inn at Tyn y Maes, we examined the rocks 
which have been cut through in forming the new road to Ban- 
gor nearly at right angles to the plane of stratification; but we 
observed only the repetition of the rocks already noticed, alter- 
nating, perhaps, 10 or 12 times with slates, differing little or 
nothing from the varieties already described. 
At Ben Glog, which is nearer to Capel Curig than the Inn 
at Tyn y Maes by about two miles, we found a considerable 
change in the appearance of some of therocks, The prevailing 
character here is so decidedly steatitic, that the rock often 
assumes the appearance of aslaty steatite, or of a talcose rock 
of a green colour, soft enough to yield easily to the nail 
on the cross fracture, «nd coated on the plane of its regular 
cleavage by a soft shining substance which appears to be green 
talc ; occasionally, however, it is harder, splitting readily into 
thin lamine, the edges of which cut glass readily, though the 
plane surfaces are soft; we conceive this, therefore, to consist of 
alternate and very thin layers of talc and quartz. Specks of 
calcareous spar appear in some places, and here and there also 
macled crystals of transparent felspar. Another rock with 
which the above are associated appears to consist of greyish 
steatite, which is very hard, owing as we assume to distribution 
of silex through the mass. This rock has been cut through close 
to the bridge of Ben Glog, exposing its enclosed masses often of 
some inches in diameter, of crystalline calcareous spar, of which 
the crevices are filled by transparent quartz: but as some of 
these rocks effervesce on the application of acid to the surface, 
the carbonate of lime appears in these instances to be generally 
disseminated throughout the mass. A rock also occurs here 
plentifully, which is finely granular, of a bluish-grey colour, and 
extremely soft, which, by exposure, loses its colour, and passes 
into a sort of yellowish slaty steatite, which is very hard, and 
perfectly resembles the steatite already noticed as having been 
found among the debris of Hlanberris Pass. It is said to be 
among the slaty talcose rock above described that the hone- 
stone is found and quarried near this place. These slates and 
rocks are interstratified in the usual direction of north-east 
and south-west. j 
On the low walls of Ben Glog Bridge, we found several 
masses of slate, and of rock having more or less of slaty struc- 
ture, containing the impressions and casts of shells. 
In the walls bounding the New Road between Ben Glog and 
Capel Curig, we observed very numerous tabular masses of a 
rock having much the aspect of a flinty slate, and perfectly 
resembling the loose fragments already described as occurring 
around Moel Shabod, and in Llanberris Pass. These tabular 
