G. H. Kinahan—Irish Esker Drift. QT 
‘ Hsker-like drift.” This appears to be the case in reference to 
Prof. Carvill Lewis’s statement in the December number of this 
Journal, where he says that the “Irish Hskers” appear to be 
adjuncts of the melting of the ice sheets. A protracted and 
careful examination into the subject seems however to demon- 
strate that this could not be the case. 
On the examination of the adjuncts of the present “ live ice” 
_ or a snow field, it will be found that the drifts due to the ice or 
the melting of the snow fields, have more or less an argillaceous 
character, they rarely except in spots, being clean sands or 
gravel. Of course rivers, having their origin in glaciers or an 
ice field, after some time may wash these gravels comparatively 
clean, but this occurs nearly invariably at some distance from 
the edge of what may be defined as the margin of the present 
moraine or glacial drift. Recent washing, that is the wash- 
ing due to river action since the “ great glacial period,” cannot 
be taken into account. 
In connection with thé marine gravels of the present day, we 
find that in the open sea-currents, all the detritusis well washed 
and sifted. Where the sea-currents are strong there is coarse 
sand or fine gravels; this is generally outside the banks; and 
in other places there is finer, but still well washed sand; while 
rarely in eddies or “heads of currents,” silt accumulates in 
small quantities. In bays or estuaries, the sand and gravel 
accumulations are not as well washed and cleaned; while still 
higher up in such situations, that is near the head of the bay, 
the accumulations due to marine action graduate in character 
into those of this drift from the destruction of which, they 
have been supplied. The true Irish eskers—that is the 
eskers of the plain and its associated valleys—have no charac- 
ters in common with those of the ridges of drift due to the 
melting of ice or snow fields; and the latter are the ridges now 
erroneously classed with the Irish eskers. On the other hand, 
all the characters of the true drift. are similar to those of the 
washed marine drifts; they in some places being well washed 
fine gravel, in others, sand; in eddies on “ beads of current”’ 
silt; and in such places as must have been bays and estuaries 
they graduate into half washed accumulations. 
Besides, what seems to have altogether escaped Prof. Lewis’s 
attention is the margin of what I have called the ‘‘ Esker sea.” 
This everywhere throughout Ireland can be traced, as below it 
the Hsker drift occurs and never above it. This margin varies 
in altitude, but in general not more so than the present spring 
tide line round the coasts, as I have already pointed out in 
papers read before the different Irish and English scientific 
societies. The tide line at the present time is higher on the 
east coast of Ireland than on the west; and at the heads of the 
