G. H. Kinahan — The Silurian Rocks of Ireland. 69 



" None of my work is guesswork ; all my conclusions are from 

 personal examination. I cannot now work out these rocks, and my 

 map must remain as it is ; the Geological Survey must complete the 

 examination," or words to this effect. 



After this interview, I paid more special attention to this subject, 1 

 and an epitome of my researches (except in respect to the equiva- 

 lents of the Dingle Beds) appears in my recently-published " Manual 

 of the Geology of Ireland." In that book I only hint at the age of 

 the equivalent of the " Dingle beds." because at the time it was 

 being written, more than a year ago, I was aware some of my 

 colleagues were engaged working out the disputed rocks of the 

 Curlew and Fintona Mountains, and I supposed they would have 

 given attention to the question as to their age. It was not till the 

 book was in print that I learned that the dispute had been ignored ; 

 although Mr. Berdoe-Wikinson's work proved that Jukes' and 

 Foot's surmises in respect to the classification of the rocks of the 

 Curlew Mountains were correct. Then, when I felt at liberty to 

 express my opinion, it was too late to do so, except in the preface of 

 the book. 



The accompanying sections (Figs. 1 and 2) show the relations of 

 the lower and upper divisions of the Old Red Sandstone to the 

 Silurian and to the Carboniferous. In one table are given the 

 sections of the Old Bed Sandstone of Silurian age, and in the other 

 most of the type sections of the true or Carboniferous Old Bed 

 Sandstone. 



In the Bally castle Coal-field, to the north-east of Antrim, Old 

 Bed Sandstone occurs interstratified in the Coal-bearing Calp. 

 This is also the case near Draperstown, county Derry, where the 

 Calp is very similar to that of Antrim, except that no workable 

 coals have been found there ; while in Armagh the Old Bed Sandstone 

 is interstratified with the Burren limestone. These three districts 

 are grouped together, as in the rocks associated with the Old Bed 

 Sandstone are found fish-remains, more or less similar among 

 themselves, and also to the fish-remains met with at Burdie House, 

 Scotland. 



To the north of the county of Dublin conglomerates occur close 

 under the base of the Coal-measures, while in the rest of Dublin, 

 Kildare, and Carlow, small patches of red conglomerate have been 

 discovered, seemingly on different geological horizons. These appear 

 to be only shore-beds, margining ancient lands ; but in the county of 

 Kilkenny, to the north-east of Thomastown, the Old Bed Sandstone 

 comes in as a distinct subdivision at the base of the Carboniferous 

 Limestone formation, and increases in thickness as it is followed 

 to the south-west. In this place, as also in the country between 

 Knocktopher and Waterford, and in Slievenaman, the rocks are of 

 the ordinary Central Ireland type (red and yellow shales, clay- 

 rocks, sandstones, and conglomerates ; the pebbles in the conglo- 



1 Foot and myself, in about 1864, wrote a paper to show that the Munster Old 

 Red Sandstone was in part Silurian and in part Carboniferous ; the paper, however, 

 was not published, as Jukes considered it to be premature. 



