52 REPORT—1852. 
Hitherto, in North Cork, North Waterford, and Kilkenny fragments of plants have 
been the only things found in the yellow sandstone. 
As we go south, the blue and gray slates increase in quantity at the expense of the 
yellow sandstones, till south of Cork, especially near Monkstown and Carrigaline, w 
get the tollowing section :— : 
Dark gray shales and slates, with occasional bands of greenish-gray Feet. 
DEAE ars aye sele, Sele onsisiniupre wietahocede. Stege tet Sus cie saat Iakate eth cae sc 400 
Bow sandstone, sometimes calcareous, and containing casts of 
Cucullea? ...... Rast shel bcud= DA BAe oPOcen es ot Bea). 50 
Dark gray shales and slates, weathering brown or yellowish, with ] ¢ 600 
occasional bands of hard sandstone, all more or less affected by ae 1000 
slaty cleavage ............ blige ole emit « » wietttele) «fete x apd tata gagetede ‘i 
Red and green slates alternating ........... aisles ae alarsjtle « bhaish eH ADOUST EOD 
Red slates, with an occasional band of yellow sandstone ........ 500 
Red slates, with gray or purple sandstones, without reaching the 
age lof the; forimatlOny, jaye. heise) eiaiern = ihs eleteeayatejers oioveiale ciel 2000 
4850 
We here lose the yellow sandstone altogether, and get below the mountain lime- 
stone, a great series of slate rocks with interstratified beds of sandstone, the prevailing 
colour of the upper portion being gray, and of the lower red, with alternating beds at 
their junction, marine fossils being found in the upper part, and no fossils at all in 
the lower. - 
Still further south, about Kinsale, these upper beds acquire a still larger development, 
being at the very least 6000 feet thick, without seeing anything like the base of them, 
and without any certainty of our having seen the top. Of this part, as we have not 
yet completed the survey, I cannot enter into details; I have however received a 
letter from my colleague, Mr. Wilson, in which he tells me that the following section 
is admirably seen in Courtiacsherry Bay :— 
Blue calcareous shales, with occasional thin bands of limestone and blue Feet. 
slates, with a few grit beds ......... Ae Cea ae J sha ule os ees eee 
Blue slates, with greenish-gray grits predominating below............ 1700 
Yellow sandstones with shale partings..............+. BBR ear re Soh ell 
Red and green slates passing down into red slates and sandstones .... 1500 
6100 
We here get the yellow sandstone coming in again just above the red rocks, having 
a vast series of blue aud gray shales and slates above it, bearing out Mr. Griffith in 
his threefold division of carbouiferous slate, yellow sandstone and old red. The 
difficulty we experience in the field is, that all these rocks are so blended at their 
junction by alternation one with another through several hundred feet of thick~ 
ness, and are near their junction, and generally, except in particular spots, so devoid 
of fossils, that we cannot hit upon any characters to enable us to draw a clear boun- 
dary between them. Starting with the old red sandstone, and calling that Devonian, 
there are no physical characters whatever enabling us to draw a boundary until we 
come to the base of the mountain limestone. We have therefore hitherto found our- 
selves compelled merely to make a shaded outline, including the upper beds, namely, 
the carboniferous slate and yellow sandstone of Mr. Griffith, looking on them in the 
light of the upper portions of the old red sandstone. If we can so consider them, we 
get the following remarkable result; that on the east, where the old Devonian land 
lay, as proved by the conglomerates, the old beaches of that formation, we find 
remains of terrestrial plants and freshwater shells; while on the south and west, - 
where the rocks get finer-grained, and where therefore the finer silts and muds were 
deposited further from the land, or in the deeper water of the sea, there we get marine 
shells coming in, and we find the whole formation gradually thickening in that direc- 
tion, swelling out from 1000 to upwards of 6000 feet. This increase of thickness, though 
it seems great, is nothing remarkable, since to acquire it, it is only necessary to suppose 
that the old sea bottom deepened very gradually, its bed inclining at no greater angle 
than 1°, or 17 in 1000, or 89 feet (14 fathoms) in a mile, if we take the distance 
from Knocktopher in Kilkenny to Kinsale; or if we supposed that the thickness of the 

