DU NOTEll SITUMINOUS COAL OF THE ARIGNA DISTRICT. 89 
at an elevation of between 710 and 1209 feet above the level of 
Lough Alien,' from whicli it is distant about tln^ee miles; a most 
excellent road leads from the lake to within 400 yards of the out- 
crop of the bottom seam of coal. The lower coal has here a slate 
roof, from which fact, I should suppose that it corresponded to the 
top coal of Aghabehy, and the upper coal here would therefore agree 
with the thin seam, numbered 15 in Sir E. Griffith's section, and which 
is thinly developed in the district to the west of Kilronan mountain. 
Though this may be probable, I am aware that it is unsafe to attempt 
to identify coal-seams merely from a correspondence in their "roof" 
or " seat. At the outcrop of the lower coal, along the northern 
brow of this mountain, the strata are clearly seen to have a sliglit 
dip away from the hill, or to the north-east. This is explained in the 
Section J\o. 3, which shows that this portion of the coal-measures 
forms the nortliern side of a low anticlinal, the prolongation of which 
to the north has been cut off by the denudation ; by tracing these 
beds, however, up the mountain, they are found, as a mass, to be 
bent synclinally and to form a shallow basin. The rise therefore 
of the coal to the hill, on its northern flank, which causes tlie beds to 
be self-draining, will, in all probability, be found to cease in tlie dis- 
tance of 250 yards. 
The lower coal-seam of Greaghnaslieve afforded the following 
section on the northern face of the mountain : — 
Seat rock, sandstone. 
Holing 6 to 8 inches in brown sandy clay, and slightly micaceous 
shale, answering to an impure fire-clay. 
Fire-clay coal, or fire-clay, with numerous bituminous layers and 
strings through it, 8 to 10 inches. 
Coal from 1 foot 4 to 1 foot G. 
Koof, black slate clay, 7 to 10 feet. 
Kock roof, sandstone. 
In my table of thickness, etc., of the coals, I have called this the 
two-foot coal. 
The upper coal seam, or that nearest to the top of the mountain, 
was not as well exposed as the lower. I traced its outcrop across 
the townland, but had not an opportunity of examining it closely. I 
was informed, however, that it is of equal thickness with the lower 
seam, but it wanted the shale holing, and its roof and floor is sand- 
stone or ''rock;" we may therefore value it as an 18-inch coal. 
From the inaccessible nature of the ground in the townland of Alta- 
VOL. YI. 
