Stratified Rocks near Killarney and Dublin, 169 



where it crosses Brickeen Island, it will be seen that the strike 

 of the chloritic quartz and shite 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'SuUivan'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. 



