On Traces of Glacial Drift. 



385 



V. Oil Traces of Glacial Drift in the Shetland Islands. 

 By C. W. Peach, Esq. 



In the summer of 1864, by invitation, I accompanied Mr 

 J. Gwyn Jeffreys, of London, on a dredging expedition to 

 the Shetland Islands. It had long been a wish on my part 

 to see more of that interesting group, from having been 

 much struck with their appearance and productions when 

 hastily passing round them with Sir R. I. Murchison, Bart., 

 on a geological trip some years before. Although Mr Jeffreys' 

 mission was a zoological one, and one into which I entered 

 heartily, I was induced, by a request from Sir E. I. M., to look 

 out for traces of glacial action on the islands we landed on. 



The result of these hasty opportunities, and, consequently, 

 imperfect observations, with all their faults, I have thought 

 might be acceptable to the Society, and must, therefore, 

 draw on your kind forbearance for all shortcomings. 



I am not aware of any paper on this subjeci in connection 

 with Shetland, with the exception of one by Dr Hibbert, 

 " On the Direction of the Diluvial Wave in the Shetland 

 Islands," published in the " Edinburgh Journal of Science" 

 for 1831, New Series, vol. iv. p. 85. At that time glacial 

 action was little thought of ; and when Dr Hibbert made 

 his survey, he merely noticed a few of the large blocks scat- 

 tered over some of the islands, and referred them all to the 

 then opinion, that they had been removed from their ori- 

 ginal beds, and transported by diluvial waves to the places 

 he found them in. Although he mentions seeing trans- 

 ported blocks on several of the islands, from not having 

 made notes at the time of observation, little is to be gathered 

 from his paper. He appears to have had his attention more 

 drawn to them by their size, unusual positions, and the old 

 world stories connected with them, as well as the black 

 agency that was said to have thrown them about. The 

 diluvial wave, he says, had a south-westerly direction. He 

 does not mention grinding and polishing, striae or scratch- 

 ing. Meagre, therefore, as my story may be, I hope it will 



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