176 Proceedings of the Royal Irish Academy. 



The principal contribution of the last-named to the subject was his 

 postulate of a huge mass of ice lying to the north of the Central Plain, 

 which he designated the " Central Snowfield." A few short extracts from 

 his writings will show his conception of the location and function of this axis 

 of dispersion. On page 260 [op. cit.) he writes :— 



" It [the " Central Snowlield "] occupies the tract lying between 

 Louo-h Corrib and Lough Mask on the west, and Lough Neagh on the 

 east — a tract coinciding with the northern portion of the Central Plain of 

 Ireland, and bordered along the north by hills and uplands, over which 

 the ice has moved in its efforts seawards." 



On a later page (290) he extends this "axis" in an easterly direction, as 

 is expressed in the following ; — 



" This axis probably terminated not far from the present coast of 

 Antrim."' 



The following sentence (p. 258) gives the physical character of the country 

 along the supposed " axis " : — 



" The average elevation of the central reservoir and source of the 

 streams [glaciers] is probably not more than 400 or 500 feet above the 

 sea ; and from this the ice moved northwards and southwards." 



He recognised that this peculiar localisation of a glacial centre in a 

 lowland region required some equally special explanation, which he sought 

 in a naive assumption of higher precipitation along this line during the 

 glacial period and even at the present day. The position of this " Central 

 Snowfield " as given in the map in this book is by no means coincident 

 with that assigned to it in J. E. KUroe's paper: in the former work the 

 " axis " is represented as passing across the southern end of Upper Lough 

 Erne, and as lying entirely to the south of Lough Allen ; in the map 

 illustrating J. E. Kilroe's paper it crosses the Eiver Erne in the neighbourhood 

 of Enniskillen, while Lough Allen is represented as lying completely to the 

 south of the ''axis." Though both maps are on a very small scale, such a 

 discrepancy of approximately 15 miles is a matter of some importance, and 

 shows how little these theories rested upon actual field observation. 



To Maxwell Close has sometimes ^ been attributed the idea of the " Centi-al 

 Axis." 1 have studied his writings very carefully, including his classic paper 



' J. R. Kilroe {op. cit., p. S) supposes an extension of this " axis" still further east 

 beyond the Antrim coast, " perhaps beyond it towards the Scottish coast opposite." 



'E.g., E. Hull, op. cit., p. 225 ; J. R. Kilroe, Proc. Belfast Nat. Field Club, Ser. ii, 

 vol. vi, Pt. iv (1912-3), pp. 647 and 649 ; Geology of the Country around Londonderry, 

 Mem. Geol. Surv., p. 54, foot-note, 



