12 B. Forbes — Geology of Donegal. 



glaciers deepened their beds. But in those beds they (or the sea) 

 must have been, otherwise the cliffs could not have been formed. 



Moreover, it is not very long ago, geologically speaking, since 

 they were there ; or else by this time the talus would have reached 

 the top of the cliff. 



On this point Mr. Geikie's paper ^ comes very opportunely. 

 There can be little doubt but that the glaciers which occupied and 

 harrowed away the debris of the cirques and of other cliff-bordered 

 valleys belonged to his third j^eriod, viz., of moraines and raised 

 beaches ; although the excavation may have gone on at intervals, 

 when there was just ice enough and not too much, all through the 

 Glacial epoch, with its many changes. 



I am glad to see Mr. Geikie's article headed, " First Paper." 

 T hope in the second paper he will correlate, as far as he is able, the 

 glacial phenomena of Scotland with those of England, and especially 

 tell us what was going on here while Scotland lay beneath its ice- 

 sheet. I shall be pleased if he can so far support my views " as to 

 allow us a corner of it. 



III. — On the Geology of Donegal. 

 By Dayid Forbes, F.E.S., etc. 



A DISCUSSION on the geological features of a locality between 

 one who has never been on the spot and another who has seen 

 so little of it as not even to know which is the bottom or top of an 

 elaborate section which he has designed to illustrate these very 

 features, is not likely to prove particularly instructive to the geo- 

 logical public, and for these reasons I would gladly have avoided it, 

 had not Mr. Green thought proper to bring my name prominently 

 forward in a paper entitled "Notes on the Geology of part of Co. 

 Donegal," in last month's Geological Magazine ; which paper, it 

 may be remarked, was read and discussed on the 20th June last at 

 the meeting of the Geological Society, although the Society sub- 

 sequently declined to print it in the Quarterly Journal. 



Mr. Green, not content with this decision, and resolved that the 

 world shall not lose the benefit of his valuable labours in a, to him, 

 evidently quite new field of geological inquiry, has reproduced it in 

 its present form, adding a lengthy criticism on some remarks which 

 fell from me during the discussion at the Society, thereby calling on 

 me for a reply, which I imagine he would not have found necessary 

 had he been present at the discussion itself. 



I would, therefore, at once state that I spoke against Mr. Green's 

 paper on principle ; for the reason that whilst it did not contain a 

 single new fact, observation, or reliable section, it showed, as he now 

 admits, an utter want of inquiry' into whether anything had pre- 

 viously been published on the subject, and also because I under- 

 stood that the amount of time he devoted to field investigation was 

 altogether so insignificant, in comparison to the importance of the 



1 Geol. Mag., Vol. VIII., p. 545. 

 2 Geol. Journ., vol. xxii., p. 553 ; and Geol. Mag., Vol. III., p. 483. 



