1908. The British Association iji Dublin. 233 



Antrim, which seemed new to him. This was sent to Mr. Moss, who 

 came to the conclusion, after a careful analysis, that it was Dopplerite, 

 a mineral found in Germany about fifty years ago by Herr Doppler, a 

 mine inspector. As found, Dopplerite looks like a black jelly, but is 

 practically non-elastic, breaking very easily under tension, with a 

 conchoidal fracture like jet or glass. It dries into a jet-like mass, losing 

 most of its bulk, and where it saturates the surrounding peat, render- 

 ing the latter almost as hard as a brick. Mr. Moss describes the mineral 

 carefully in the Scientific Proceedings of the Royal Dublin Society for 

 July, 1903, and inthis Journal in the following month. He gives a list of 

 the places in which it has been found in Germany and Switzerland, and 

 mentions that in one case a stem of a tree, embedded in sand under 

 peat, was found quite converted into Dopplerite. Mr. A. W. Stelfox, in 

 recent years, noticed it in a bog in the West of Ireland; and I found it 

 plentiful, not in veins, as at Sloggan Bog, but in small isolated patches, 

 and saturating the peat, at Drumshambo, near Cookstown. Here the 

 dried peats cut from it were as firm as bricks. The only instance I can 

 find of its occurrence in the British Isles outside Ireland is in Co. 

 Durham, in a pitfall at Tantobie, where a substance was found in 1905 in 

 pockets and clefts that "seems to be Dopplerite from the description 

 given by Dr. G. A. Smytlie in the Proceedings of the University 

 of Durham Philosophical Society for 1906. There seems to be more 

 carbon in the Irish specimens than in the English examples. Mr. Moss 

 and Dr. Smythe both consider the substance well worth more attention 

 and research, the former stating that he considers it the nearest 

 approach to prussic acid occurring in nature. 



OX THE IGNEOUS ROCKS OF THE OUTER BLASKET ISLAND. 



BY PROF. J. JOI.Y, D.SC, F.R.S. 



This contribution had reference to an investigation of the most 

 westerly of the Blasket Islands, the two small rocks known as the Foze 

 Rocks. A landing was effected in specially favourable w^eather and 

 samples of the rocks secured. These show that the two islands are 

 alike composed of black fine-grained lava, containing in parts many 

 vesicles and even pumiceous in structure. The sections show much 

 more or less turbid glass, with minute lath-shaped crystals and fine opaque 

 dust, probably magnetite. It is suggested that this represents part of 

 the lava plains of Silurian age which appear on the mainland and at 

 Tnishvikillane ; thus enlarging this volcanic area to one of the most 

 extensive in Great Britain. 



