GEOLOGICAL SOCIETY OF DUBLIN. 
S3 
Feet. 
Thickness of the Limestone,.1000 
Middle or Calp Limestone, ...... 100 
Lower Limestone,. 1000 
Another section between Pallaskenry and Koynes would give :■— 
Feet. 
Upper Limestone,.250 
Calp,. 1400 
Lower Limestone,.1500 
Professor Jukes suggests that the great thickness of the Dublin Calp 
may he owing to the thinning out of the upper Limestone, and that the 
coal-measure shales may rest on the Calp of the central counties with¬ 
out the intervention of any upper Limestone. 
I think there can he now very little doubt of the existence of the 
Calp, and although we may he compelled to differ with Mr. Kelly as to 
his views on this subject, we must feel obliged to him for the inde¬ 
pendent manner in which he has stated his opinions, and for having 
brought to the test of discussion the accuracy of one of the most impor¬ 
tant land-marks in Irish geology. We all owe a deep debt of gratitude 
to Dr. Griffith for his Map of Ireland, and the multifarious information 
which he has given us upon all subjects connected with it. 
Messrs Jukes and Du Hoyer contributed to the Geological Section 
two joint papers :— 
1. On the geology of an interesting neighbour, Lambay. Although 
noticed some years since by Mr. Hamilton, its structure, I believe, 
was never before minutely and accurately described. 
2. On certain rocks found between the bays of Tralee and Pantry. 
This latter paper has reference to a subject brought before the As¬ 
sociation by Dr. Griffith, and there are also two other papers, one by Mr. 
Wynne, on the Galtees, and another by Mr. Joseph O’Kelly on a sec¬ 
tion across Slievenamuck Mountain, which have a very close connexion 
with Dr. Griffith’s paper. 
On the sedimentary rocks of the south of Ireland, some beautiful 
illustrative sections were exhibited at the meeting. 
It appears, in the words of Dr. Griffith, that the Old Red Sandstone 
strata, consisting of alternate beds of red and green shales, red sandstones 
and conglomerates extend more or less continuously in an east and west 
direction, through the counties of Tipperary, Limerick, and Cork. We 
find the Old Red Sandstone lying conformably below the Lower Lime¬ 
stone and Yellow Sandstone of the Carboniferous System, and resting on 
the upturned edges of the Silurian rocks in an unconformable position, 
till, reaching the Old Bed strata in the county of Kerry, they are found 
preserving the same relative position to the brownish-red grits, and the 
red, green, and purple clay-slates of the Dingle district which conform 
to and overlie the fossiliferous Silurian rocks of Kerriter’s Cove; these 
being again overlaid unconformably on the western shore at Sybil Head 
by the beds of the Old Red series. 
