36 Notices of Memoirs — 



the remarkable indications of former glaciers ; in some places it 

 would seem as if they had disappeared but a few years previously, 

 and occasionally, whilst climbing some smoothly rounded buttress, 

 one almost expects to see the ice itself creeping through the next 

 depression." 



More than fifty years ago J. T>. Forbes drew attention to the 

 traces of ancient glaciers in the Cuillin Hills, but it has remained 

 for Mr. Alfred Harker to work out and portray in masterly style the 

 somewhat complex glacial history of this mountainous region. 



The Cuillins, though formed of rocks wholly younger in age than 

 the London Clay, are better entitled to take rank as mountains than 

 any other elevations in Britain. The main range takes a semi- 

 circular form ; it is built up of a great laccolitic mass of gabbro, 

 and its sharp and rugged peaks rise in many places above 3,000 feet. 

 Separated from these by Glen Sligachan is a range of ' Eed Hills ' 

 formed of granite and granophyre, whose smooth and dome-like 

 elevations, mostly under 2,500 feet, appear in marked contrast 

 both in colour and outline with their dark and grim neighbours. 

 Those who tread the stony track-way from the Sligachan Hotel to 

 Loch Coruisk, may feel fatigue at the end of their journey, but 

 they cannot fail to be fascinated with the grandeur of the Glen. 



Mr, Harker points out that during the period of maximum 

 glaciation these Skye mountains sustained a small local ice-cap, 

 round which the great Scottish ice-sheet flowed north-westwards 

 and south-eastwards, traversing the peninsula of Sleat, the islands 

 of Pabba and Eaasay, and that portion of Skye which lies north 

 of Portree. Both the Cuillins and the Eed Hills afforded gathering- 

 ground for the local ice, under which they came to be wholly buried, 

 for its thickness was probably not less than 3,000 feet. This local ice 

 and that of the Scottish sheet were in equilibrium for a long time 

 along their line of confluence; but the movements of the local ice 

 are indicated by the directions of stride on rock-surfaces, and by the 

 distribution of boulders of local and recognizable rock-types. There 

 is a noticeable absence of foreign boulders in central Skye, except 

 near the shore, where they occur occasionally up to as much as 

 75 feet above sea-level. Along this margin, however, there are 

 relics of the ' hundred foot ' raised beach, which prove that the land 

 stood lower by that amount at the close of the Glacial Period. 



Interesting observations are made on the movement of the ice 

 during the great glaciation, and it is pointed out that the striae 

 necessarily give only the direction of movement of the lower layers 

 of the ice, and this appears to be true also in great measure of the 

 dispersal of boulders. 



The natural outward flow of the ice was in general closely guided, 

 as regards its lower layers, by the form of the ground, but as the 

 land for many miles from the Cuillins was wholly buried in ice, 

 the form of the ground exerted only a partial control over the 

 direction of flow. Thus it is not improbable that the upper layers 

 followed in places a somewhat different course from that proved 

 with regard to the lower layers. 



