154 THE Rev. MAXWELL H. CLOSE, 
vicinity. It is perfectly certain that it must have been the rock- 
scoring agent which produced the boulder-clay ridges. Having 
ascertained this, we can often recognise the course of the flows of 
the universal ice-sieet by the mere inspection of an accurately 
shaded map. See the shaded Ordnance inch maps, Nos. 100, 
101,110,and 111. These drumlins are even more strikingly 
displayed in other parts of Ireland. | 
The rock-scorings and these ridges show that the great glacial 
flow from the north-westward was divided not far from 
Maynooth, evidently . by the obstruction of the Dublin and 
Wicklow Hills; see the glacial map of Ireland in Prof. Hull’s 
Physical Geology and Geography of Ireland, p. 210. Agassiz, 
when in Dublin in 1840, having seen but little of the glacial 
phenomena cf the neighbourhood, naturally supposed that those 
hills must have been a centre of glacial dispersion. But it is 
very. interesting and remarkable to find that they were not so, 
but that they were invaded ab eatia by a great ice-flow which 
can be traced backward to the less important hills of Fermanagh. 
They had, however, afterwards, their own small local glaciers as 
we shall see presently. 
STRATIFIED Drirt.—Immediately over the Lower Boulder clay, 
which was clearly the moraine dw fond of the great ice-flow 
from the north-westward, comes a deposit of stratified water- 
arranged and washed gravels and sands. These, which we shall 
eall the Middle Sands and Gravels, extend from the present sea 
-level up to a considerable elevation on the hills, They reach 
1,100 feet on the S.E. side of the Three Rock Mountain, 1,300 
feet on the W. side of that hill, on the summit of the col econnect- 
ing it with Kilmashogue Mountain, 1,250 feet at 21 miles W. 
by 8. of the last, and the same elevation at one mile W. of this 
last on the eastern side of Mount Pelier. The distance between 
the first and the last mentioned spots is five miles. 
These elevated parts of the gravels and sands are as well 
washed and sorted as those on the low grounds; they moreover 
consist as largely of foreign materials; although resting at those 
heights on granite hills they are part of the “limestone oravel.”’ 
Pieces of flinty chalk and other far-transported stones and 
fragments of marine shells can he found in them as in the low- 
lying gravels. The shells found in the gravels of this neighbour; 
