GLACIOLOGY OF THE SOUTH ORKNEYS. 857 



underlying rock surface. The layers were all of similar density and appearance, with no 

 shearing of one over another. In the lowermost eight or ten feet there is a good deal 

 of englacial debris, chiefly as a dirt band between ice layers. This contorted and faulted 

 appearance disappeared later on after a fall of ice, the new surface exposed not 

 showing it. 



Allan Glacier. 

 This small glacier, on the west side of Uruguay Cove (Plate VII.), occupies a fine 

 deep cirque shut in on three sides by high vertical cliffs, entirely cutting it off from 

 any of the surrounding ice. Its terminal front is divided into two by a partial 

 nunatak. On the larger southern face the stratification is seen horizontally, with 

 nothing unusual to distinguish it from other glaciers. The northern part shows 

 the layers bent upwards, where they end against the nunatak and to a less extent 

 also against the northern side wall (Mount Ramsay). In the centre they are sinuous, 

 moulding themselves closely to the irregularities of the rocky bed. The rock peeps 



Text-fig. 14. — Ice-cave under termination of Allan Glacier. 



out in several places below the terminal face, and in one spot a cave is left between 

 the ice and the lee side of a rock boss. This cave extends back for some 30 feet, 

 the rock-floor sloping sharply upwards and backwards. The ice-roof has been 

 moulded very exactly to the rock behind, and has kept a marked fluted aspect, 

 while projecting free in a beautiful curve over what may be some day the lee side 

 of a roche moutonnee. Several transverse fissures 4 to 5 inches in width run 

 right across the roof of the cave. The ice is clear, but containing a fair number of 

 rock fragments, all small and angular, although some show striae. On the floor 

 there is much earthy morainic matter. The temperature of the cave the only day 

 on which I was inside it felt very much warmer than the outside air, which at the 

 time was a little under zero Fahrenheit, but I had no thermometer with me to 

 measure it accurately. 



Clijf Glaciers. 



Small cliff glacierettes of incipient glacier ice are not infrequent at various places 

 around the coasts on narrow rock terraces above precipitous cliffs (see Plate IV. 

 fig. 2, and Plate IX. fig. 1). A particularly well-developed one is to be seen on 

 the west side of Mossman Peninsula overhanging Wilton Bay. This shows strati- 

 fication like the larger glaciers, except that it is not horizontal but undulatory. 



