169 
Stratified Rocks near Killarney and Dublin, 
where it crosses Brickeen Island, it will be seen that the strike 
of the chloride quartz and slate beds on the south side of the 
fault is unconformable with the strike of the old red sand- 
stone and carboniferous limestone on the north of it, and that 
the ends of the strata of both formations abut obliquely 
against the opposite sides of the fault. This fact will be at 
once understood by reference to the plan given in Plate 
III. 
The lower portion of the strata on the north side of the 
fault consists of old red sandstone : commencing near the shore 
of the lower lake at Cullinagh to the east of O’Sullivan’s 
Cascade, we have a succession of beds of coarse-grained red 
conglomerate, similar to those already described as occurring 
at the northern entrance of the Gap of Dunloe ; these strata, 
which dip to the east, are succeeded by alternating red and 
light gray quartzose beds, which in an ascending order con- 
tinue to Glena Bay, the dip gradually changing from the 
east towards the south. At Glena Bay we fall into the line 
of the strike of the strata of the Gun rock, a small island 
situated immediately to the west of Brickeen Island, near 
Brickeen Bridge. At the Gun rock the strata consist of light 
gray quartzose rock alternating with thin beds of reddish gray 
limestone, which dip to the south at an angle of 40°. On the 
north point of Brickeen Island, these strata are succeeded by 
alternations of red and reddish gray quartzose rock, red slate, 
and red limestone, the general dip being 25 E. of S. at an 
angle of 35°. These strata abut obliquely against the fault 
to the north of the Banqueting House of Glena, and also 
where it crosses the western portion of Brickeen Island. 
Still ascending in the series, the above-mentioned strata are 
succeeded by alternations of red clay slate, yellowish green 
clay slate, and red limestone, which may be considered to 
form the upper portion of the old red sandstone series : 
above them we find a succession of beds, consisting of coarse 
greenish gray slate containing calamites, greenish gray cal- 
careous slate, and impure gray limestone, succeeded by beds 
of gray quartzose sandstone with partings of black clay slate, 
and alternations of gray limestone. These strata form the 
lowest portion of the carboniferous limestone series, to which 
I have given the name of the yellow sandstone*. Above 
the yellow’ sandstone we have the black carboniferous slate, 
which here alternates with gray limestone, the slate as at 
Kenmare predominating near the commencement; but as the 
* In most localities the colour of the sandstone is yellowish gray, and 
the siliceous rock forms by much the most important feature in the series. 
