ORIGINAL ARTICLES. 
The Glaciation of Ireland. 
By Percy F. KENDALL. 
OE ING the year 1920 two contributions on the subject of 
Irish Glacial Geology have appeared, differing greatly in scope 
and treatment. Mr. Wright’s paper on ‘‘ Minor Periodicity in Glacial 
Retreat’ is frankly speculative, but his speculations are based upon 
an accurate and fairly exhaustive survey of the glacial evidences 
in the country about the head of Kenmare River, the deep ria 
lying between Bantry Bay, Dingle Bay, and the lake region of 
Killarney. 
The phenomena of which an interpretation is attempted belong 
to a late stage of the glaciation of the West of Ireland when the 
ice had shrunk back from the central plain and was apparently 
reduced to a series of independent systems of glaciers radiating 
from centres only a few miles from the seaward ends of certain 
of the rias. 
Of all the other districts that have been studied none seems so 
remarkable and anomalous as this. The author shows by a map 
(fig. 1) the direction of ice-flow, from which it appears that the 
radiant point whence the ice flowed in every direction was not, as 
might have been expected, the lofty hill cluster of Macgillicuddy’ S 
Reeks culminating in Carrantuohill, 3,414 feet high, but either 
in the bed of the ria itself or in the low hills 1,100 to 1,300 feet high 
that lie along its northern shore. From this centre the passes 
through the Reeks were over-ridden, only the higher summits rising 
as nunataks above the ice. 
The cause of this astonishing phenomenon has never been dis- 
cussed—perhaps not even considered—but it is to be hoped that 
light will be thrown on the problem in the promised general memoir 
on Kerry. No doubt the mere fact that the last remnants of the 
great ice-sheet lingered in the west finds a ready explanation in 
the present meteorological conditions, the mountainous margin 
inducing copious precipitation ; the problem is, however, to explain 
why, with a broad valley opening directly upon the coast and 
a dwindling mountainous margin on each side, the discharge should 
have taken these inland courses instead of flowing freely into the 
Atlantic. The temptation to invoke differential earth movement 
is checked by the reflection that lake-terraces extending for 12 miles 
“show no departure from horizontality which is not included 
within the limits of error inseparable from such observations of 
level as it has been found possible to make ” 
Mr. Wright describes this lake that occupied the upper part of 
the Kenmare Valley in considerable detail. It was held up by the ice 
to the level of the col at Morley’s Bridge 320 feet O.D., and at this 
