ON THE GLACIAL PHENOMENA OF THE OUTER HEBRIDES. 



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49. On the Glacial Phenomena of the Long Island, or Outer 

 Hebrides. Second Paper. By James Geikee, LLJ)., F.R.S., 

 F.G.S., of H.M. Geological Survey. (Read May 8, 1878.) 



[Plate XXXIII.] 



Contents. 



I. Introduction. 



II. Lewis (Additional Notes). 



1 . Geological structure. 



2. G-laciation of hilly districts. 



3. Shelly Boulder-clays and Intergla- 



cial beds. 



III. Harris. 



1. Physical features. 



2. Geological structure. 



3. Glaciation. 



4. Till or Boulder-clay. 



5. Erratics. 



6. Morainic debris and moraines. 

 7- Origin of erratics and moraines. 

 8. Freshwater lakes and sea-lochs. 



IV. Islands in the Sound of Harris. 



Y. North List. 



1. Physical features. 



2. Geological structure. 



3. Glaciation. 



4. Till or Boulder-clay. 



5. Erratics. 



6. Freshwater lakes and sea-lochs. 



VI. Benbecula. 

 VII. South Uist. 



1. Physical features. 



2. Geological structure. 



3. Glaciation. 



4. Till or Boulder-clay. 



5. Erratics, moraines, and local gla- 



ciation. 



6. Freshwater lakes and sea-lochs. 



VIII. Islands in the Sound op 

 Barra. 



IX. Barra. 



1. Physical features. 



2. Geological structure. 



3. Glaciation. 



4. Till or Boulder-clay. 



5. Erratics. 



X. Islands south of Barra. 



1. Bhaterseidh. 



2. Maoldomhnuich. 



3. Saundreidh. 



4. Flodeidh. 



5. Lingeidh. 



6. Grianamal. 



7. Papeidh. 



8. Miuleidh. 



9. Bearnareidh. 



XI. General remarks on the physi- 

 cal features op the Long Island. 



XII. Summary of results and 

 Conclusion. 



1. Primary or general glaciation. 



2. Shelly Boulder-clays and Intergla- 



cial beds. 



3. Local glaciers. 



4. Postglacial and recent submer- 



ge 



I. Introduction. 



In a former paper* I gave some account of the glaciation of 

 Lewis, the northern portion of the Long Island, and showed that 

 the whole of that region had been rubbed and ground in a direction 

 from south-east to north-west by land-ice which could only have 

 come from the mainland. In the present paper I give some addi- 

 tional observations on Lewis, most of which were made during my 

 first visit to the island, while others were noted upon a subsequent 

 occasion, when I was accompanied by my colleague, Mr. R. Ethe- 



* Quart. Journ. Geol. Soc. vol. xxix. p. 532. 



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