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Proceedings of the Royal Irish Academy. 



only in thickness, but in their texture. A coarse, clean gravel, with 

 an abundant sandy matrix, is tlie characteristic deposit. The pebbles are 

 chiefly basalt and chalk ; with them are occasional pieces of the Cushen- 

 cluneurite, the riebeckite granophyre of Ailsa Craig, and other erratics 

 common in the local Boulder-clays, from the washing down of which 

 the gravel is probably in large part derived. The base is usually 

 sandy ; and at various levels in the gravels, sandy beds several feet 

 thick alternate with the coarser material. The several zones are often 

 cross-bedded ; thus, in the section examined by the Belfast Field Club 

 in 1889, two thick beds of coarse gravel were separated by several feet 

 of sands, all three zones having a different bedding. At the harbour 

 ballast-pit (^on fig. 2), recently examined, on the other hand, 10 feet 

 of gravels and 3 feet of underlying sands had a uniform, slight dip 

 northward from top to base (Plate YII.). 



A sufficient number of sections of the Curran beds is now available 

 to allow us to understand the modelling of the spot. In fig. 3 these 

 sections are shown, excepting a section along the line JFX (Bay Eoad), 

 which has been already illustrated in the Academy's Froceedings (3rd 

 series, vol. iv., plate 1, 1897). The position of the several sections is 

 marked on the plan, fig. 2. The section exposed on the beach at 

 Curran Point {P on plan) shows the gravels resting on Boulder-clay 

 at a little above high water, '^o section is then available till we come 

 to the railway cuttings, where the fine series of beds exposed by the 

 digging of the Belfast Pield Club Committee in 1889 {B on plan) shows 

 a depression of the Boulder-clay, occupied by the Estuarine Clay series, 

 overlaid by a great depth of beach-gravels. Sections A and C were 

 measured by us on our recent visit. The three sections A, Cform a 

 west-to-east cross-section along the southern edge of the railway cutting, 

 A being distant 150 feet from B, and^ 170 feet from C. Only 350 feet 

 northward of this cross-section, the Boulder-clay has risen up to form 

 the islet already described, being on the summit of the knoll in the 

 Aluminium Works. The section at Z in the harbour ballast-pit, 300 

 feet eastward of F, shows the rapid dip of the Boulder-clay, and its 

 sea-eroded surface. Finally, 800 feet to the northward of the knoll, 

 we have the section F(now destroyed) at the old pottery, where again 

 the Boulder-clay has dipped, and the Estuarine Clay fills the hollow, 

 with beach-gravels above it. The cross-section TFX along Bay Eoad, 

 referred to above as already figured in these Proceedings, must finally 

 be added to the series. 



To trace briefly the history of the Curran. In early post-Glacial 

 times, we find a ridge of Boulder-clay occupying roughly the site of 



