Devon and Cornwall^ Belgium, the Eifel, Sfc. 281 



raised to their present level; a speculation into which I do 

 not think it necessary to enter, the established fact of the 

 difference of position and association, and consequently of 

 date as to origin, being sufficient for my present purpose. 

 Other matter is to be found scattered through Mr. Flolds- 

 worth's observations, which comes very well in corroboration 

 of the general view which I have mven of the structure and 

 composition of that district in my memoir on the south of 

 Ireland ; although Mr. Holdsworth nowhere draws the dis- 

 tinction himself between the transition conglomerate and sand- 

 stone, and the overlying conglomerate and sandstone of the 

 Monavoullagh range, further than by considering the former 

 as a conformable, and the latter as an unconformable forma- 

 tion. On the contrary, he gives it as his opinion that all the 

 conglomerates and sandstones which he has noticed in the 

 eastern part of Waterford are identical, excepting perhaps 

 those occurring on the north-west of the city of Waterford 

 and those around Dunmore on the western side of Waterford 

 harbour, which he conceives may be of more recent forma- 

 tion, but no reason is assigned for this opinion. The identity 

 spoken of, however, seems mainly to refer to the similarity 

 of mineral composition, respecting which there can be no 

 difference of opinion. 



But to return to Mr. Griffith. It is clear from the pre- 

 ceding that he has confounded together the old red sandstone 

 formation, properly so called, with the red conglomerate, 

 sandstone, and slate, which occasionally occur as constituent 

 beds in a transition country. 



The horizontal position of the Monavoullagh sandstone 

 conglomerate is quite in accordance with what is observable 

 in the detached portions of the same formation which are 

 studded over the northern border of the clayslate table-land, 

 overlooking from the south the valley of the Suire, and where 

 in the year 18 14", when first exploring that country, I found 

 the sandstone conglomerate reposing unconformably on the 

 truncated edges of the subjacent clayslate. Mr. Holdsworth 

 appears to have made a similar observation in a quarry ad- 

 jacent to the road between Kilmacthomas and Portlaw, where 

 the junction of the clayslate and the conglomerate is very dis- 

 tinctly marked, the slate there being thrown up nearly per- 

 pendicular*. 



Indeed, when we consider the long-drawn range of the 

 Monavoullagh from north to south, being nearly at right 

 angles with the eastern and western strike of the bordering 

 older stratified rocks, both on its eastern and western con- 



* Journal of Geol. Soc. of Dublin, vol. i., part 2, p. 95. 



