Sir,
Early descriptions of pro-talus ramparts
Recent correspondence in the Journal of Glaciology concerning early descriptions of pro-talus ramparts (Reference ButlerButler, 1986, 1987; Reference BallantyneBallantyne, 1987; Reference PorterPorter, 1987) has failed to include mention of an interesting account of these features, and their mode of formation, from Ireland (Reference KinahanKinahan, 1894). There are few detailed descriptions of pro-talus ramparts in Ireland and consequently Kinahan’s paper, while being known to Irish glacial and periglacial geomorphologists as an early and important contribution to the subject (Reference Warren, Schliichter and RotterdamWarren, 1979; Reference Lewis, Edwards and WarrenLewis, 1985), is probably unknown beyond these shores.
Although Kinahan’s report was published 21 years after those by Reference DrewDrew (1873) and Reference WardWard (1873), he had identified
“some forty years ago ⋯ peculiar accumulations evidently in some way due to ice or its adjuncts”.
He originally attributed these features to “the Glacial period; while knowledge since gained would seem to prove that these terminal moraines may possibly be accumulating at the present day”.
Despite naming such features “terminal moraines”, Kinahan’s account of their formation clearly indicates that the debris travelled across the surface of an inclined snow bed
“In the cooms and under the high cliffs great snow drifts accumulated ... . As is always the case after a severe frost, blocks and other detritus are displaced by falls when the thaw comes on; and if the fall is from a cliff over one of these drifts, the blocks and other stuff slide over it and form round its edge a terminal moraine”.
In addition to the use of “terminal moraine” to describe these deposits, Kinahan referred to one particular feature as
“a massive esker-like high accumulation of shingle”.
While this terminology is perhaps unfortunate, the features he identified as resulting from this process are undoubtedly those we now call pro-talus ramparts.
Kinahan recognized these land forms in Counties Cork, Donegal, Galway, Mayo, Wexford, and Wicklow, and named specific locations where the process of debris accumulation could be observed during severe winters. He also brought to the attention of the scientific community the local term for such debris accumulations � cloghsnatty (correctly clogha snachta; Reference Warren, Schliichter and RotterdamWarren, 1979) or snow stones, which implies that their mode of formation was well understood long before the scientific study of glacial and periglacial phenomena had become established. Sadly, clogha snachta was not adopted by the scientific literature as were the Gaelic terms eiscir (esker) and druim (drumlin).
Finally, Kinahan’s observations of clogha snachta were not confined to Ireland. He provided a brief description of a visit to the Canadian Rockies and, although
“My visit … was so short that my conclusions can scarcely be of much value … it was long enough to explain points in the Irish drift phenomena previously inexplicable”.
