320 



PROCEEDINGS OF THE GEOLOGICAL SOCIETY. 



[Mar. 7, 



Sir Roderick Murchison communicated the contents of a report 

 made by M. Fouque, the envoy to Santorinoof the Academy of Sciences 

 of Paris, to the eparch of Santorino. M. Eouque states that a 

 fissure had opened between the George Promontory and the new 

 island Aphroessa, and that the points of eruption are simply the 

 sites of the deepest holes in the line of rupture, and that the non- 

 existence of a true crater is owing to the small quantity of ejected 

 matter and the feebleness of the eruption. Owing to the recent 

 progress made in the study of volcanos, M. Fouque is enabled 

 to state that the eruption of Nea Kaimeni never presented more than 

 a very moderate degree of intensity. M. St. Claire Deville has 

 shown that there exists a constant and certain relation between the 

 degree of intensity of a volcano in action and the nature of 

 the volatile elements vomited at its mouth ; thus, in an eruption 

 of maximum intensity, the predominant volatile product is chloride 

 of sodium, accompanied by salts of soda and potash ; an eruption of 

 the second order gives off hydrochloric acid and chloride of iron ; one 

 of the third degree, sulphuric acid and salts of ammonia ; and of the 

 fourth, or most feeble phase, steam only, with carbonic acid and the 

 combustible gases. Applying this principle to Nea Kaimeni, it ap- 

 pears that the eruption never exceeded the third degree of intensity ; 

 and when it created the greatest alarm it gave off only sulphuric 

 acid, steam, and combustible gases, or products of the third and fourth 

 orders of volcanic activity. M. Fouque therefore agrees with other 

 observers in believing that the fears of the inhabitants of the islands 

 were very nearly unfounded. 



2. On the Caeboniferous Slate {or Devonian Rocks) and the Old 

 Red Sandstone of South Ireland and North Devon. By J. 

 Beete Jukes, Esq., M.A., F.R.S., F.G.S. 



Contents. 



I. Introduction. 



II. Sketch of the Upper Palaeozoic 

 Rocks of the Southern portion 

 of Ireland. a 



1. Wexford. 



a. Red Sandstones and Con- 

 glomerates in the Lower 

 Silurian rocks. 



2. Hook Head. 



3. Waterford. 



4. Extent of the Old Red Sand- 



stone north and west of Water- 

 ford. 



a. The Kiltorcan Section. 



b. The Comeragh Mountains. 



5. Old Red Sandstone of North 



Cork, South Waterford, and 

 South Kerry. 



6. The Lower Limestone Shale of 



the Youglial and Ardmore^ 



and the Cork and Midleton 

 Troughs. 



7. The Knockadoon and Sheeps 



Head Anticlinal, and the coun- 

 try to the south of it. 



8. Old Head of Kinsale. 



9. Cape Clear and Mizen Head An- 



ticlinals. 



10. The Bantry Bay Trough. 



11. The Berehaven Promontory, and 



that of Iveragh and Dunkerron. 



12. Dingle Beds. 



13. Grradual changes in the Litholo- 



gical character of the Old Red 

 Sandstone. 



14. G-eneral Conclusions on the Rocks 



of the South-west of Ireland. 



15. Sudden Changes from thick lime- 



stone to mechanically formed 

 rocks. 



