252 ICE-EROSION IN THE CUILLIN HILLS, SKYE. 



EXPLANATION OF MAP. 



This sketch-map shows the central part of Skye on the scale of about i inch to a mile. The general 

 character of the surface relief is roughly indicated by the contour-lines corresponding with altitudes of 

 1000, 2000, and 3000 feet above sea-level. 



The doubly-barbed arrows indicate the movement of the ice during the stage of maximum 

 glaciation, as deduced from the striated surfaces, the dispersal of boulders, etc. These arrows belong in 

 the north-eastern corner of the map to the ice-sheet from the Scottish mainland, but elsewhere to the 

 native ice-cap. In the Red Hills, which occupy much of the eastern portion of the map, the data are in 

 general insufficient to determine the movement of the ice with any precision. 



The singly-barbed arrows given in several parts of the map indicate the movement of the native ice 

 -during the later stages of glaciation, when the disturbing factor of the Scottish ice-sheet was removed. 



Certain lines drawn on the map are explained as follows : — A A A is the mid-stream-line of the Glen 

 Sligachan ice-stream. Among the boulders in the drift, granite preponderates over gabbro to the right of 

 this line and the reverse to the left. B is the corresponding line for the surface erratics, belonging to a 

 later stage of the glaciation ; in Glen Sligachan itself this line is practically coincident with the preceding, 

 but diverges from it at Sligachan Bridge. C C is the western limit of granite boulders carried by the 

 southward-moving ice. D D is the northern limit of peridotite and picrite boulders from Coir' a' Ghrunnda 

 and An Sgiiman. E is the moraine of Coir' a' Ghrunnda. 



