1892-93.] 53 1 



small bay we find represented each great division of the geolo- 

 gical record. Shales that carry us back to the Palaeozoic era, and 

 recall the gradual submergence of the Devonian continent 

 beneath the waters of the Carboniferous ocean ; sandstones that 

 bring us to the Mesozoic era, and restore for us the vast Triassic 

 lakes ; dykes that link us with the great basaltic sheets of Ter- 

 tiary time, and, covering the low surrounding cliffs, drift 

 deposits that bring us to post-Tertiary periods and gradually 

 forward to the time we are considering. 



Encroachments of the sea similar to those described have 

 taken place on the adjacent coast. Although no landmark 

 survives, it is estimated that within living memory the sea has 

 advanced more than 150 feet at Cooper's Bay, near Holy wood ; 

 and Cooper's Green, once a favourite resort for rural games, has 

 now, with part of an inner adjoining field, completely disappeared. 

 In confirmation of the foregoing notes it is interesting to trace 

 the changes recorded on successive maps of the Ordnance Survey. 

 On the six-inch map, surveyed and engraved in 1834, we find both 

 the quarry at Cultra Point and the road leading to Cultra Quay, 

 while on the same map, revised in 1858, and engraved in i860, 

 Cultra Point has a more smoothed and rounded appearance, the 

 quarry is no longer marked, and all traces of the road are gone. 

 A comparison of successive Admiralty charts gives indications of 

 somewhat similar interesting changes in Belfast Lough. In the 

 chart for 1883, corrected up to 1 891, the three-fathom line 

 (close to the end of the new cut recently opened in continuation 

 of the Victoria Channel) is more than 800 feet nearer to Belfast 

 than in the chart for 1841, corrected up to 1856. Within the 

 same period the three-fathom line has also approached more 

 closely to Holywood and to Carrickfergus. 



After an accurate description of the various geological forma- 

 tions at Cultra, the long and interesting record that they show us, 

 and the part that their varying hardness has borne in their own 

 recent erosion by the sea, the writer concluded — We have glanced 

 at the apparent destruction of a small land surface, we have seen 

 its materials loosened, disintegrated, falling a prey to the energy 



