138 Correspondence—J. W. Gregory. 
no clue to the movement of the ice which made the kame. No 
doubt the area was invaded by ice from the north-west; but the 
movement at the time of the kame formation is not shown by the 
original home of the boulders. According to Professor Cole (Reg. 
Geol., ili, p. 329, received after my MS. had been sent to the Royal 
Society) the materials of the Tyrone eskers were distributed from 
south to north. I am sorry to differ from Dr. Charlesworth 
regarding an Ulster kame, and if he will publish his evidence I will 
carefully consider it; but I find it difficult to realize how this kame, 
steeply descending the hill to the north and with its curves concave 
to the south-east, can be due to ice from the north-west, although 
much of its material originally came from that direction. 
Professor Kendall claims that by insertion on Fig. 9 of two 
arrows from Professor Sollas’s map I have unintentionally con- 
tradicted the statements in the text that the ice flowed in the 
opposite direction. I described the Dunmore eskers in reference to 
the claim that they were deposited within ice which was moving 
at right angles to their trend. For, if so, and if glaciers have any 
power of erosion, it would appear clear that the eskers must have 
been formed after the ice had ceased to flow across their sites. I 
agree with Professor Sollas that the course of the ice was along a 
line trending north-west and south-east; and to show that 
Professor Sollas adopted that course I inserted the two arrows 
from his map. The legend of the figure quotes them as from 
Professor Sollas, and as marking “the course of the ice move- 
ment ’’, not its direction along that course. It is made clear in the 
text that I consider that the direction adopted should be reversed ; 
but I left the arrows to prevent any possible suspicion that I] was 
claiming Professor Sollas’s agreement with the direction of move- 
ment as well as with its course. Whether the ice moved from or 
towards the north-west being immaterial to the formation of these 
kames, I mentioned my conclusion and the nature of the evidence, 
but did not give it in detail. 
(6) Professor Kendall also objects to my insertion on a sketch 
map (Fig. 11), showing the relations of the eskers to the 300 foot 
contour of some arrows indicating the ice movement according to 
Mr. W. B. Wright. The first objection raised is that Mr. Wright’s 
map refers to the maximum extension of the ice and not to the stage 
to which I assign the eskers. But the theory which I was proposing 
to amend is that the eskers were formed by rivers within the great 
ice-sheet ; and one fact I hoped to show by the figure was that many 
of the chief eskers trend across the line of the movement of the 
ice, and were formed on its margin during its retreat, and not 
within it. To that argument the map is relevant. The second 
objection is that I have unduly magnified the lines. In order to 
prevent attaching to Mr. Wright’s lines a significance as to details 
greater than the scale of his map would warrant, I ended the lines 
to the south against the hill country of Sheve Bloom, between 
