tional way, so far as the present paper is concerned, is that 

 the deposits now under description exhibit two of the most 

 perfectly-preserved examples of Permo-Carboniferous moraines 

 that have come under my notice. 



Rosetta Head Moraine. 



Rosetta Head, or the Bluff as it is more commonly 

 called, possesses a striking profile. It is a rounded hill, 

 317 ft. in height, washed by the sea on three of its sides, 

 and on the landward exhibits a steep and broken crest, which 

 passes into a low, smooth curve at about half the elevation 

 of the hill, thereby giving an easy access to the summit 

 (see plates iii. and iv.). The south-eastern side of the hill 

 gives a very fine illustration of intrusive granite weathered 

 into huge masses and spheroidal blocks. On the landward 

 side the granite forms a junction with fine-grained mica- 

 schists, the latter being intimately penetrated with strings 

 and shots of granite, while at greater distances from the 

 igneous rocks there are conspicuous quartz- veins and "blows." 

 The schists, in their landward extension, are largely obscured 

 by a covering of clay and large boulders which can be traced 

 from the slopes of the Bluff to an indefinite distance in a 

 northerly direction. 



The dissimilar features of the two sides of the Bluff arise 

 from a geological unconformity of high- time value. The sea- 

 ward side, as well as the summit, consists of metamorphic 

 schists intimately penetrated and contorted by granitic veins. 

 The landward slopes are formed of a wide ridge of morainic 

 material which, although dating from the Palaeozoic age, has 

 scarcely been altered from its original incoherent condition 

 during the many geological periods that have transpired since 

 its deposition. 



The Bluff originally formed part of an east and west 

 ridge that possessed steep faces towards the north. These 

 scarps, facing the north, form parts of the old-world topo- 

 graphy which the ancient ice-sheet impressed on the district. 

 It is a characteristic feature of glacier movement that the 

 ice exerts the greatest denuding force at the further extremi- 

 ties of a hill in the direction of its own flow. In such 

 situations the rocks have less powers of resistance, and are 

 cut into and carried away by the ice-plough under a process of 

 "plucking. " 



An escarpment of the kind just mentioned would, under 

 the influence of an ice-flow, tend to produce two classes of 

 effects: firstly, a large amount of material for transporta- 

 tion, gathered from the wearing back of the scarp ; and 

 secondly, a lee-face, under the protection of which morainic 



