STR aah tah) ath 
td Naa 
660 PROF, W. BOYD DAWKINS ON THE CARBONIFEROUS, [| Nov. 1902, * 
These cliffs also (as is proved in the preceding paper) were carved out 
of Keisley Limestone, a rock which may be expected to occur under- 
neath the mantle of Drift 3 in the north of the island, in its proper 
place between the Basement Carboniferous and the Ordovician 
quartzites and sandstones which overlook the buried seaworn 
northern plateau. 
Discussion [ON THE TWO FOREGOING PAPERS |. 
Mr. Lamptvex, in defending his rendering of the Peel Sandstones 
on the Geological Survey-map, remarked that he would gladly have 
accepted the reading of this exceedingly obscure ground given by 
the Author in his paper of 1895, if this had agreed with the 
available data. But as he found that important field-evidence 
in the outcrops around Glenfaba had been overlooked, he was 
compelled to attempt an independent rendering in accordance with 
this evidence. The borings in this area, referred to by the Author, 
were made long ago, and the evidence in regard to them was 
unsatisfactory. He readily acknowledged that any mapping, under 
the conditions, could be only approximately correct. 
The same remarks applied with even stronger force to the 
mapping of the northern plain, which was really only a portion of 
the Irish sea-bottom, made into land by the thick Glacial deposits. 
For his own part, the speaker had always regretted that 1t was 
officially necessary for him to produce a map of the solid rocks 
underlying this ground; but, given the necessity, nothing more 
could be done than had been done. In the Memoir now in the 
press he had recognized the possibility that Silurian rocks might 
occur in this tract. 
He was in accord with the Author in his amended reading of the 
borings at the northern margin of the island; but he thought that it 
was due to himself to mention that the error in the Author’s 
previous interpretation of the Ballawhane boring, now so frankly 
acknowledged, would not have been discovered if the speaker had 
not himself examined the cores. The Author, in a previous paper, 
had based far-reaching conclusions on the supposed Peel rocks of 
this boring, now acknowledged to be Lower Carboniferous. 
The speaker’s examination of the cores from all the borings had 
convinced him that no equivalents of the Peel Series had been 
found in them. The Permian breccias of these borings could be 
directly correlated with the Permian breccia or Brockram of the 
Cumberland coast, but this correlation could not be sustained in 
respect to the Peel rocks. He deprecated the use of the terms 
‘ Brockram’ and ‘ Magnesian Limestone’ applied by the Author 
to parts of the Peel Series, and also the reference of pebbles to the 
‘ Yoredales,’ etc., on the basis of general resemblance only. The 
condition of the limestone- fragments in the Peel Conglomerates 
was not that of the Neeson este es in the Baoely ad of 
Cumberland and of the northern borings. 
As to the Author’s insistence that the Peel Series was identical 
